Otty Lake - Jebbs Creek

Otty Lake - Jebbs Creek

otty lake catchment

Tay River Subwatershed Report 2017

OTTY LAKE CATCHMENT

LandCoverTay-RiverOtty-Lake---Jebbs-Creek-001-001Figure 1 Land cover in the Otty Lake catchment (2014)

The RVCA produces individual reports for 14 catchments in the Tay River subwatershed. Using data collected and analysed by the RVCA through its watershed monitoring and land cover classification programs, surface water quality and in-stream conditions are reported for the Tay River, Tay Watershed lakes and Tay tributaries along with a summary of environmental conditions for the surrounding countryside every six years, which includes analysis of data collected through the programs along with local information provided by stakeholders up to 2017.

This information is used to better understand the effects of human activity on our water resources, allows us to better track environmental change over time and helps focus watershed management actions where they are needed the most to help sustain the ecosystem services (cultural, aesthetic and recreational values; provisioning of food, fuel and clean water; regulation of erosion/natural hazard protection and water purification; supporting nutrient/water cycling and habitat provision) provided by the catchment’s lands and forests and waters (Millennium Ecosystem Assessment 2005).

Figure 1 shows the geographic extent of the Otty Lake catchment along with its land cover classes. The Table of Contents provides a hyper-linked list of the articles that have been prepared for the Otty Lake Catchment Report.

Table of Contents: Otty Lake Catchment Report
Catchment Facts Section 1.0
Water Quality Conditions Section 2.0
Riparian Conditions Section 3.0
Land Cover Section 4.0
Stewardship and Water Resources Protection Section 5.0
Accomplishments Section 6.0
Challenges/Consequences/Issues Section 7.0
Actions/Opportunities Section 8.0

For other Tay River catchments and the Tay River Subwatershed Report, please see Rideau Valley Conservation Authority Subwatershed Reports.

1.0 Otty Lake Catchment: Facts

1.1 General/Physical Geography

Drainage Area

52.8 square kilometres; occupies 6.6 percent of the Tay River subwatershed; 1.2 percent of the Rideau Valley watershed.

Geology/Physiography

The Otty Lake catchment resides within part of the physiographic region known as the Algonquin Highlands. In the Tay River Subwatershed, this ancient and hilly geologic region is made up of such Precambrian rocks as marble, conglomerates, and dark or colour banded granite-like rocks. A large area of younger sandstone flanks the catchment’s northern boundary. A veneer of glacial drift (glacial till, sand etc.) overlies the bedrock.

Municipal Coverage

Drummond/North Elmsley Township (18.7 km2; 35.4% of catchment)

Tay Valley Township (34.0 km2; 64.4% of catchment)

Town of Perth (0.1 km2; 0.2% of catchment)

Stream Length

All watercourses (including headwater streams): 98.6 km.

1.2 Vulnerable Areas

Aquifer Vulnerability

The Mississippi-Rideau Source Water Protection program has mapped the north boundary of this catchment as a Significant Groundwater Recharge Area and all of the catchment as a Highly Vulnerable Aquifer. There are no Well-Head Protection Areas in the catchment.

Wetland Hydrology

A watershed model developed by the RVCA in 2009 was used to study the hydrologic function of wetlands in the Rideau Valley Watershed, including those found in the Otty Lake catchment.

 

1.3 Conditions at a Glance

Fish Community/Thermal Regime

Warm and cool water recreational and baitfish fishery with 19 species observed in Jebbs Creek during 2016.

Headwater Drainage Features

Primarily classified as wetland and natural features with minimal modifications.  

Instream/Riparian Habitat

Jebbs Creek: Low to high habitat complexity with increased habitat complexity observed in the lower and upper reaches of the system within the catchment along with a healthy diversity of plant types and levels throughout the surveyed sections; however, there are areas of extensive plant growth (64 percent) which are dominated by the invasive aquatic plant, European frogbit. Dissolved oxygen conditions in Jebbs Creek vary along the system for both warm and coolwater fish species.

Land Cover Change (2008 to 2014)
Catchment Woodland Crop-Pasture Meadow-Thicket Settlement
Hectares -7 -3 -1 +11
Land Cover Type (2014)
Catchment Woodland Wetland Water Crop-Pasture Settlement Transportation Meadow-Thicket
Percent 41 21 14 13 5 3 3
Shoreline Cover Type (30 m. riparian area; 2014)
Catchment % Jebbs
Creek
% McLaren
Lake
% Otty
Lake
% Streams* %
Wetland 44 Wetland 83 Woodland 51 Woodland  48 Wetland 51
Woodland 37 Woodland 10 Wetland 49 Settlement 35 Woodland 32
Settlement  8 Settlement 5 --- --- Wetland 14 Crop-Pasture 12
Crop-Pasture  8 Transportation 1 --- --- Transportation 3 Transportation 2
Transportation  2 Crop-Pasture 1 --- --- --- --- Settlement 2
Meadow-Thicket 1 --- --- --- --- --- --- Meadow-Thicket 1
*Excludes Jebbs Creek
 

Significant Natural Features

Tay Marsh Provincially Significant Wetland

Tay Marsh Regional Candidate Area of Natural and Scientific Interest, Life Science.

Species at Risk (Elemental Occurrence)
Species at Risk Status
Blanding's Turtle Threatened
Black Tern Special Concern
Eastern Milksnake Special Concern
Eastern Musk Turtle Special Concern
Northern Map Turtle Special Concern
Snapping Turtle Special Concern
Water Quality for the Protection of Aquatic Life
Water Quality Source Jebbs Creek McLaren Lake Otty Lake
Surface Chemistry Good Poor to Fair Fair to Good
Instream Biological Poor to Fair --- ---

Jebbs Creek: Benthic invertebrate samples are dominated by species that are moderately to highly tolerant of high organic pollution levels.

Water Wells

Approximately 620 operational private water wells in the Otty Lake catchment. Groundwater uses are mainly domestic.

Wetland Cover

Wetlands are reported to have covered 31 percent of the Otty Lake catchment prior to European settlement, as compared to 21 percent (or 11.1 square kilometres) of the area in 2014. This represents a 31 percent (or 5.0 square kilometre) loss of historic wetland cover.Fourteen percent of the remaining wetlands are regulated leaving 86 percent (or 9.5 square kilometers) unregulated.

1.4 Catchment Care

Environmental Management

The Otty Lake Association prepared the Otty Lake Management Plan (2008) to provide a summary of what is known about the Otty Lake catchment along with the community’s vision for the lake and a list of its main concerns and actions to address them. This has been followed-up with the release of the Otty Lake Five-year Review (2014) and annual State of the Lake Reports initiated by the OLA in 2014, which is a comprehensive report providing information regarding water quality, the lake fishery, wildlife habitat, shoreline planting initiatives, the amounts of zebra mussels and algae, among many other topics.

Development along Jebbs Creek (Rideau Ferry Road to the Tay River) and in, and adjacent to, the Tay Marsh Provincially Significant Wetland in the catchment is subject to Ontario Regulation 174-06 (entitled “Development, Interference with Wetlands and Alterations to Shorelines and Watercourses”) that protects the hydrologic function of the wetland and also protects landowners and their property from natural hazards (flooding, fluctuating water table, unstable soils) associated with them.

Three Environmental Compliance Approvals were sought in the catchment for waste management sites and an industrial sewage works.

Environmental Monitoring

Chemical surface (in-stream/lake) water quality collection by the RVCA since 2003; prior to this date, the Otty Lake Association has coordinated/undertaken other chemical water quality analysis (see Section 2 of this report).

Benthic invertebrate (aquatic insect) surface (in-stream) water quality collection by the RVCA in Jebbs Creek since 2005 (see Section 3.3.1 of this report).

Fish survey and stream characterization survey by the RVCA on Jebbs Creek in 2016 included taking measurements and recording observations on instream habitat, bank stability, other attributes and preparing a temperature profile (see Section 3 of this report).

Otty Lake shoreline assessed as majority regenerative (236 properties; 49 percent); majority ornamental (172 properties; 36 percent) and majority natural (74 properties; 15 percent) by the Love Your lake Program.

Thirty-two drainage feature assessments were conducted by the RVCA in 2016 at road crossings in the catchment. The protocol measures zero, first and second order headwater drainage features and is a rapid assessment method characterizing the amount of water, sediment transport, and storage capacity within headwater drainage features (see Section 3.4 of this report).

Classification of Otty Lake catchment land cover types derived by the RVCA from colour aerial photography that was acquired during the spring of 2008 and 2014 (see Section 4.1 of this report).

The Mississippi Rideau Septic System Office has conducted 348 mandatory septic system re-inspections on 250 properties around Otty Lake from 2012 to 2017 and nine voluntary septic system re-inspections on seven properties around McLaren and Mud Lake from 2004 to 2017 (see Section 5.5 of this report).

Groundwater chemistry information is available from the Ontario Geological Survey for one well (#13-AG-022) located in the catchment

Stewardship

Sixty-four stewardship projects were completed by landowners with assistance from the RVCA (see Section 5 of this report).

2.0 Otty Lake Catchment: Water Quality Conditions

Surface water quality conditions in the Otty Lake catchment are monitored by the Rideau Valley Conservation Authority’s (RVCA) Watershed Watch Program and Baseline Water Quality Monitoring Program. Watershed Watch monitors watershed lakes to assess nutrient concentrations, water clarity, dissolved oxygen availability and pH. The baseline water quality program focuses on streams; data is collected for 22 parameters including nutrients (total phosphorus and total Kjeldahl nitrogen), Escherichia coli (E. coli), metals (like aluminium and copper) and additional chemical/physical parameters (such as alkalinity, chlorides, pH and total suspended solids). Figure 2 shows the locations of monitoring sites in the catchment. 

Figure 2 Water quality monitoring sites on Otty Lake and Jebbs Creek
Figure 2  Water quality monitoring sites on Otty Lake, McLaren Lake and Jebbs Creek
 

Water Quality Rating in the Otty Lake Catchment

The water quality ratings across this catchment range from "Poor to Good" (Table 1); with a rating of "Poor to Fair in McLaren Lake; "Fair to Good" in Otty Lake and "Good" in Jebbs Creek as determined by the Canadian Council of Ministers of the Environment (CCME) Water Quality Index. "Poor" indicates that water quality is frequently threatened or impaired with conditions that often depart from natural or desirable levels.  A "Fair" rating indicates that water quality is usually protected but is occasionally threatened or impaired; conditions sometimes depart from natural or desirable levels.  A rating of "Good" indicates that only a minor degree of threat or impairment is observed and conditions rarely depart from natural or desirable levels.  Each parameter is evaluated against established guidelines to determine water quality conditions. Those parameters that frequently exceed guidelines are presented below. Data has been analysed over the 2006-2017 period for general trends and conditions. Table 1 shows the overall rating for the monitored surface water quality sites within the catchment and Table 2 outlines the Water Quality Index (WQI) scores and their corresponding ratings.

Table 1 Water Quality Index ratings for the Otty Lake Catchment; scores from which ratings were determined are shown in brackets.
SiteLocation 2006-20082009-20112012-20142015-2017
JEB-01Jebbs Creek at Rideau Ferry Rd. Good (87)Good (83)Good (87)Good (92)
DP1Otty LakeFair (77)Good (88)Good (88)Fair (77)
DP1McLaren LakePoor (59)Fair (72)Poor (61)Poor (50)
Table 2 Water Quality Index ratings and corresponding index scores (RVCA terminology, original WQI category names in brackets)
RatingIndex Score
Very Good (Excellent)95-100
Good80-94
Fair65-79
Poor (Marginal)45-64
Very Poor (Poor)0-44

2.1 Otty Lake Water Quality

Surface water quality conditions in Otty Lake have been monitored by RVCA’s Watershed Watch Program since 2002. Data from the deep point site (DP1) has been used to calculate the WQI rating for Otty Lake, which ranged from Fair to Good over the 2006-2017 period (Table 1). Moderate nutrient concentrations, good oxygen availability and clear water all influenced this rating. The following discussion explains how each of the monitored water quality parameters contributes to the lake’s water quality.

This report also considers data from eight additional shoreline sites that are monitored around the lake. These sites have not been included in the calculation of the CCME WQI rating, as they are not monitored with the same frequency as the deep point site. However, they do provide important information on water quality conditions in the near shore areas. For locations of shoreline sites (A-H) please see Figure 2.  Additional resources also include the extensive data collected by the Otty Lake Association (OLA)  and results from the Ontario Ministry of the Environment Lake Partner Program (LPP); the results from these programs have been incorporated in this discussion to support the results produced by RVCA.

2.1.1 Otty Lake Nutrients

Total phosphorus (TP) is used as a primary indicator of excessive nutrient loading and contributes to abundant aquatic vegetation growth and depleted dissolved oxygen levels. The Provincial Water Quality Objective (PWQO) is used as the TP Guideline and states that in lakes, concentrations greater than 0.020 mg/l indicate an excessive amount of TP within the water column. Concentrations below 0.010 mg/l are generally considered to be minimal and unlikely to have problems associated with nutrient loading.

Total Kjeldahl nitrogen (TKN) is used as a secondary indicator of nutrient loading. RVCA uses a guideline of 0.500 mg/l to assess TKN[1] within surface waters.

 
Nutrients at the Otty Lake Deep Point

TP and TKN sampling results collected by the RVCA are presented in Figures 3 to 6. Variability has occurred in the sampled TP concentrations at this site (Figure 3 and 4), however no significant trend[2] was observed in the 2006-2017 dataset. Eighty-nine percent of samples analysed for TP were less than the TP guideline and the average concentration was 0.013 mg/l (Table 3).  TKN concentration also showed variability and similar to TP results no significant change was observed (Figures 5 and 6). Ninety-three percent of reported results were below the TKN guideline and the average TKN concentration was 0.411 mg/l (Table 3).

Figure 3  Total phosphorus sampling results at the deep point site (DP1) on Otty Lake, 2006-2017
Figure 4  Average total phosphorus results at the deep point site (DP1) on Otty Lake, 2006-2017
Figure 5  Total Kjeldahl nitrogen sampling results at the deep point site (DP1) on Otty Lake, 2006-2017
Figure 6  Average total Kjeldahl nitrogen results at the deep point site (DP1) on Otty Lake, 2006-2017
Table 3 Summary of nutrient results for Otty Lake over the monitoring periods, 2006-2017
Total Phosphorous 2006-2017
SiteAverage (mg/l)Below Guideline No. Samples Source
DP10.01389%45RVCA
DP10.01290%30OLA
DP10.01398%130LPP
Total Kjeldahl Nitrogen 2006-2017
SiteAverage (mg/l)Below Guideline No. Samples Source
DP10.41193%45RVCA
DP10.51053%30OLA

Table 3 also summarises nutrient data from the OLA and LPP monitoring programs.  Please note that the OLA data set was only available from 2012-2017 and has fewer samples; also the LPP does not sample for TKN, therefore no data is available to compare results for that parameter.  There was no significant difference found in the average TP concentration across the three monitoring programs; the same result was found when comparing the TKN results for RVCA and OLA[3] . Comparably to the RVCA data set, there was no indication of a change (trend) in the nutrient concentrations over the monitoring period in the OLA data set.   The LPP TP data did show a slight decreasing trend in TP concentrations from 2006-2017.  The increased number of samples (duplicates collected at the deep point) appear to have reduced the variability in this data set and perhaps made the trend more evident.

Overall, the data presented indicates that nutrient concentrations may be considered moderate with occasional instances of exceedances in the mid-lake, deep water site on Otty Lake. 

Nutrients around Otty Lake

The average nutrient concentrations at monitored shoreline sites around the lake vary from year to year (Figures 7 and 8). Please note that in the 2006-2017 monitoring period sites A, B, C and E were sampled yearly; while sites D, F, G and H were only sampled in 2007, 2012 and 2017.

Average total phosphorous concentrations are below the TP guideline at the majority of sites; with the exception of site A, which typically shows exceedances (Figure 7). Site A is at the head of Marl Bay where Jebbs Creek narrows and is also the outflow of the lake; the cumulative flow through this portion of the lake dominated by wetland features may result in elevated nutrients at this site.  No significant trend was noted in concentrations over the monitoring period.  

Average TKN concentrations were also below the guideline at the majority of monitored sites; again, an exception to this is site A and E (Figure 8). Site E is located near the outflow of McLaren Lake which has had persistently elevated TKN levels due to the influence of wetlands that flow into that waterbody.  

Figure 7  Average total phosphorus concentrations at RVCA shoreline monitoring sites on Otty Lake, 2006-2017
Figure 8  Average total Kjeldahl nitrogen concentrations at RVCA shoreline monitoring sites on Otty Lake, 2006-2017
Summary of Otty Lake Nutrients

Otty Lake nutrient concentrations are generally below the guidelines, with few exceedances. It is possible that occasional problems with nutrient enrichment (i.e. algal blooms or excessive plant growth) may be observed in shallow, sheltered bays.

Efforts such as the diversion of runoff and enhanced shoreline buffers are important to continue to protect and enhance water quality, and reduce future nutrient increases. Nutrient exceedances may be partially attributed to the natural aging of a lake and basin characteristics. All residents can help minimise their impact on the lake by reducing nutrient inputs through practices such as proper maintenance of septic systems, keeping shorelines natural and using phosphate free soaps and detergents.  Promotion of sound stewardship and protection around lake are important to maintain and protect water quality conditions into the future.

2.1.2 Otty Lake Water Clarity

Water clarity is measured using a Secchi disk during each deep point sample. Table 4 summarises the recorded depths with an average depth of 5.8 m and shows that all readings have exceeded the minimum PWQO of 2 m indicating that algae in the water column is not at excessive levels (good water clarity). Less than 2 m will indicate overproduction in a lake or significant inputs to the water column that are limiting light availability. Figure 9 shows that no individual reading has been below the guideline and measured depths range from 3.1 m to 9 m. A decreasing trend was observed within the 2006-2017 data set, indicating that Secchi depths have been reduced over this period. It should be noted that Secchi depths in many waterbodies have been influenced by the colonization of zebra mussels resulting in clearer waters than may have been seen prior to the introduction of this species; zebra mussels have been reported in Otty Lake since 2005.  The declining trend may be attributed to the population dynamics of this species as minimal changes have been noted in other monitored parameters (i.e. nutrients, pH, dissolved oxygen conditions).

Table 4 Summary of Secchi depths recorded at the deep point site (DP1) on Otty Lake, 2006-2017
Secchi depth 2006-2017
SiteAverage (mg/l)Below Guideline No. Samples 
DP15.8100%41
Figure 9  Recorded Secchi depths at the deep point site (DP1) on Otty Lake, 2006-2017
 
Summary of Otty Lake Water Clarity

Waters in Otty Lake are very clear and sufficient sunlight is able to penetrate the water column to support aquatic life and provide sufficient visibility for safe recreational use (boating, swimming).

2.1.3 Otty Lake Fish Habitat

Two other factors, dissolved oxygen/temperature and pH were also assessed to provide an overall sense of the health of Otty Lake from a fish habitat perspective. 

2.1.3.1 Otty Lake Dissolved Oxygen and Temperature 

The red bars in Figure 10 show the depths where suitable conditions exist for warm water fish species (temperature less than 25°C and dissolved oxygen greater than 4 mg/l) at the deep point site. The vertical axis represents the total lake depth at each site where the profile is taken.  Suitable conditions typically decline throughout the summer to about 10 m of the water column, a very small portion of the water column met the requirements in the late summer of 2006 and 2016. Overall, no significant change was noted in conditions through the 2006-2017 period.  

Figure 10  Depths suitable for warm water fish species at the monitored deep point site (DP1)
 

2.1.3.2 Otty Lake pH

pH is a basic water quality parameter used to assess the acidity of water, an important factor for aquatic life. Figure 11 shows monitored pH values over the 2006-2017 period.

Figure 11  pH concentrations at the deep point site (DP1) on Otty Lake, 2006-2017
 

The majority of samples for the monitored period are within guidelines established by the Canadian Council of Minister's of the Environment which state that pH should be between 6.5 and 9 to protect aquatic life (Table 5). Surface water’s that are found to be more alkaline (higher pH) are common in many regions of the Tay River subwatershed and can generally be attributed to the geology rather than anthropogenic activities. Biological activities such as increased photosynthesis from algal blooms and plant growth may also influence pH. 

Table 5 Summary of pH results at the deep point site (DP1) on Otty Lake, 2006-2017.
pH 2006-2017
SiteAverage (mg/l)Within Guideline No. Samples 
DP18.22100%41

 

Summary of Water Quality for Fish Habitat in Otty Lake

Overall the water chemistry data at the deep point describes suitable habitat conditions for fish species such as bass, walleye and pike. There is some evidence that the warming of the water column in the late summer/fall and limited oxygen availability at deeper depths may minimise the amount of habitat for some more sensitive species. pH conditions are within the end of the range recommended for the protection of aquatic life. Overall, the data indicates a healthy environment for aquatic species.

2.1.4 Otty Lake E. Coli

The RVCA samples for E. coli at their monitored shoreline sites twice each sampling season. E. coli data was not used in the calculations of the WQI rating for the lake due to differences in sampling frequency and site locations. E. coli data has been collected by both RVCA and OLA and is summarised in Table 6. The OLA samples for E. coli at 31 sites in Otty Lake, generally one to three times annually.

Throughout the 2006-2017 period 96 percent of samples collected by RVCA were below the E. coli guideline of 100 colony forming units (CFU) per 100 ml set by the PWQO; across the lake the count at the geometric mean [2] was 4 CFU/100ml (Table 6). The OLA E. coli data set also showed that the geometric mean of E. coli counts around the lake are minimal (2 CFU/100ml) with 99 percent of samples below the guideline (Table 6);  providing further support for little indication of bacterial contamination around the lake.

Table 6 Summary of E. coli results for Otty Lake, 2006-2017
E. coli 2006-2017
SiteGeometric mean (CFU/100ml)Below Guideline No. Samples Source
Otty Lake496%122RVCA
Otty Lake299%324OLA
Figure 12 E. coli counts at RVCA monitored shoreline sites on Otty Lake, 2006-2017
 

Figure 12 shows the distribution of counts across all RVCA shoreline sites. Site E, generally has higher results than other sites, but is not consistently elevated and should not be a cause for concern. All sites fell well below the guideline of 100 CFU/100ml.

Summary of Otty Lake Bacterial Contamination

The results presented above indicate that bacterial contamination is not a significant concern in Otty Lake and the water should be safe for recreational use such as swimming and boating.

 

2.2 McLaren Lake Water Quality

Surface water quality conditions in McLaren Lake have been monitored by RVCA’s Watershed Watch Program since 2006. Data from the deep point site (DP1) has been used to calculate the WQI rating which ranged from "Poor-Fair" in the 2006-2017 period (Table 1). Moderate to elevated nutrient concentrations and periods of limited oxygen availability influenced this rating. The following discussion explains how each of the monitored water quality parameters contributes to the lake’s water quality.

2.2.1 McLaren Lake Nutrients

Total phosphorus (TP) is used as a primary indicator of excessive nutrient loading and contributes to abundant aquatic vegetation growth and depleted dissolved oxygen levels. The Provincial Water Quality Objective (PWQO) is used as the TP Guideline and states that in lakes, concentrations greater than 0.020 mg/l indicate an excessive amount of TP within the water column.  Concentrations below 0.010 mg/l are generally considered to be minimal and unlikely to have problems associated with nutrient loading.

Total Kjeldahl nitrogen (TKN) is used as a secondary indicator of nutrient loading. RVCA uses a guideline of 0.500 mg/l to assess TKN[1] within surface waters.

Nutrients at the McLaren Lake Deep Point

TP and TKN sampling results  are presented in Figures 13 to 16. Variability has occurred in the sampled TP concentrations at this site (Figure 13 and 14), however no significant trend was observed in the 2006-2017 dataset. Seventy-two percent of samples analyzed for TP were less than the TP guideline and the average concentration was 0.017 mg/l (Table 3).[5]  TKN concentrations were also variable over the monitoring period; as with TP results no significant change was observed (Figures 15 and 16). Most sample results exceeded the guideline (only 13 percent were below 0.500 mg/l) and the average TKN concentration was elevated at 0.636 mg/l (Table 3).

Figure 13 Total phosphorus sampling results at the deep point site (DP1) on McLaren Lake, 2006-2017
Figure 14 Average total phosphorus sampling results at the deep point site (DP1) on McLaren Lake, 2006-2017
 
Figure 15 Total Kjeldahl nitrogen sampling results at the deep point site (DP1) on McLaren Lake, 2006-2017
Figure 16 Average total Kjeldahl nitrogen sampling results at the deep point site (DP1) on McLaren Lake, 2006-2017
 
Table 7 Summary of nutrient results for McLaren Lake over 2006-2017 monitoring period (Highlighted values indicate average concentrations that exceed the guideline.)
Total Phosphorous 2006-2017
SiteAverage (mg/l)Below Guideline No. Samples 
DP10.01772%48
Total Kjeldahl Nitrogen 2006-2017
SiteAverage (mg/l)Below Guideline No. Samples 
DP10.63613%48
Summary of McLaren Lake Nutrients

Overall, the data presented indicates that nutrient concentrations may be considered to range from moderate to elevated with regard to nitrogen.  This can be attributed to the wetland area that drains into McLaren Lake; wetlands hold high levels of nutrients in their soils which may be flushed into the lake during periods of higher flows. Though development around the lake is fairly minimal, efforts by property owners such as the diversion of runoff and enhanced shoreline buffers are important to continue to protect and enhance water quality and reduce future nutrient increases. All residents can help minimise their impact on the lake by reducing nutrient inputs through practices such as proper maintenance of septic systems, keeping shorelines natural and using phosphate free soaps and detergents.

2.2.2 McLaren Lake Water Clarity

Water clarity is measured using a Secchi disk during each deep point sample. Table 8 summarises the recorded depths with an average depth of 3.09 and shows that the majority (98 percent) of readings have exceeded the minimum PWQO of 2 m indicating that algae in the water column is not at excessive levels (good water clarity). Less than 2 m will indicate overproduction in a lake or significant inputs to the water column that are limiting light availability. Figure 17 shows recorded readings relative to the guideline; measured depths range from 1.78 m to 5 m. As with Otty Lake, a decreasing trend was observed within the 2006-2017 data set, indicating that reduced Secchi depths are becoming more common. It should be noted that Secchi depths in many waterbodies have been influenced by the colonization of zebra mussels resulting in clearer waters than may have been seen prior to the introduction of this species; zebra mussels were first reported in McLaren Lake in 2006.  The declining trend may be attributed to the population dynamics of this species as no other changes have been noted in other monitored parameters (i.e. nutrients, pH, dissolved oxygen conditions).

 
Table 8 Summary of Secchi depths recorded at the deep point site (DP1) on McLaren Lake, 2006-2017
Secchi 2006-2017
SiteAverage (m)Below GuidelineNo. Samples 
DP13.0998%43
Figure 17 Recorded Secchi depths at the deep point site (DP1) on McLaren Lake, 2006-2017
 
Summary of McLaren Lake Water Clarity

Waters in McLaren Lake are clear and sufficient sunlight is able to penetrate the water column to support aquatic life and provide sufficient visibility for safe recreational use (boating, swimming).

2.2.3 McLaren Lake Fish Habitat

Two other factors, dissolved oxygen/temperature and pH were also assessed to provide an overall sense of the health of McLaren Lake from a fish habitat perspective. 

2.2.3.1 McLaren Lake Dissolved Oxygen and Temperature

The red bars in Figures 18 show the depths where suitable conditions exist for warm water fish species (temperature less than 25°C and dissolved oxygen greater than 4 mg/l) at the monitored deep point site. The vertical axis represents the total lake depth at the site where the profile is taken.  Suitable conditions typically decline throughout the summer to about 4 m in the water column; this is generally due to very low oxygen availability below this depth.  Overall, no significant change was noted in conditions between the 2006-2017 period.  

 
Figure 18 Depths suitable for warm water fish species at the deep point site (DP1) on McLaren Lake, 2006-2017
 

2.2.3.2 McLaren Lake pH

pH is a basic water quality parameter used to assess the acidity of water, an important factor for aquatic life. Figure 19 shows monitored pH values over the 2006-2017 period.

Figure 19 pH concentrations at the deep point site (DP1) on McLaren Lake, 2006-2017
 

All results were within the guideline established by the Canadian Council of Minister's of the Environment which state that pH should be between 6.5 and 9 to protect aquatic life (Table 9).

Table 9 Summary of pH results at the deep point (DP) site on McLaren Lake, 2006-2017
pH 2006-2017
SiteAverage (mg/l)Within Guideline No. Samples 
DP18.02100%41
Summary of Water Quality in McLaren Lake for Fish Habitat

Overall the water chemistry data at the deep point describes suitable habitat conditions for warm water fish species. The limited oxygen availability at deeper depths may limit the success of some sensitive fish populations or aquatic species. pH conditions are within the end of the range recommended for the protection of aquatic life.

2.3 Jebbs Creek Water Quality

There is one stream site on Jebbs Creek monitored in the Otty Lake catchment (JEB-01, Figure 2).  Analysis of the data is based on samples collected from 2006 to 2017. Water quality at this site is reported as “Good” (Table 1) as determined by the Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI). The score at this due to the majority of monitored parameters having results below established guidelines. For more information on the CCME WQI, please see the Tay River Subwatershed Report.  Only those parameters with exceedances that influenced the rating will be discussed in the following sections.

2.3.1 Jebbs Creek Nutrients

Total phosphorus (TP) is used as a primary indicator of excessive nutrient loading and may contribute to abundant aquatic vegetation growth and depleted dissolved oxygen levels. The Provincial Water Quality Objective (PWQO) is used as the TP Guideline and states that in streams concentrations greater than 0.030 mg/l indicate an excessive amount of TP.

Total Kjeldahl nitrogen (TKN) is used as a secondary indicator of nutrient loading. RVCA uses a guideline of 0.500 mg/l to assess TKN [1] within surface waters.

Tables 10 and 11 summarise average nutrient concentrations at the monitored site on Jebbs Creek and show the proportion of results that meet the guidelines.

Table 10 Summary of total phosphorous results for Jebbs Creek, 2006-2017.
Total Phosphorus 2006-2017
SiteAverage (mg/l)Below GuidelineNo. Samples
JEB-010.02290%70
Table 11 Summary of total Kjeldahl nitrogen results for Jebbs Creek, 2006-2017 (Highlighted values indicate average concentrations that exceed the guideline.)
Total Kjeldahl Nitrogen 2006-2017
SiteAverage (mg/l)Below GuidelineNo. Samples
JEB-010.63329%70

The majority of TP results (90 percent) were below the guideline with an average concentration of 0.022 mg/l (Table 10). There is not much seasonal variability observed at the site apart from elevated results observed in September (Figure 20). There was one result of 0.150 mg/l collected in September of 2011 that was significantly elevated and should not be considered representative of conditions (Figure 21). Please note that no samples are collected over the winter months. Overall there was no significant trend in the monitoring data throughout the 2006-2017 period (Figure 21).    

 
Figure 20  Average monthly total phosphorus concentrations in Jebbs Creek, 2006-2017.
Figure 21  Distribution of total phosphorus concentrations in Jebbs Creek, 2006-2017.
 

TKN results show that the bulk of results exceeded the guideline (Figure 23); 29 percent of samples were below the guideline and the average concentration was elevated at 0.633 mg/l (Table 11). TKN concentrations appear to increase throughout the summer months (Figure 22).  However, as with TP results, a single elevated sample in September of 2011 is influencing the monthly average concentration (Figures 22 & 23).  Overall there was no significant trend in the monitoring data throughout the 2006-2017 period (Figure 23).

Figure 22  Average monthly total Kjeldahl nitrogen concentration in Jebbs Creek, 2006-2017
Figure 23  Distribution of total Kjeldahl nitrogen concentrations in Jebbs Creek, 2006-2017
 
Summary of Jebbs Creek Nutrients

The data shows that nutrient enrichment is a feature of Jebbs Creek with regards to TKN. This is likely due to the influence of surrounding wetland areas. Wetlands are naturally rich in nitrogen and appear to be contributing to the concentrations in this creek.  Though this is likely to be a natural condition it is important to reduce human impacts wherever possible. Strategies to reduce nutrient inputs may include diversion of runoff to the creek from surrounding developed areas (i.e. residences and roadways) and enhanced shoreline buffers.

 

2.3.2 Jebbs Creek E. Coli

E. coli is used as an indicator of bacterial pollution from human or animal waste; in elevated concentrations it can pose a risk to human health. The PWQO of 100 colony forming units/100 milliliters (CFU/100 ml) is used to assess E. coli. Counts greater than this guideline indicate that bacterial contamination may be a problem within a waterbody.

Table 12 summarises the geometric mean[4] for the monitored site on Jebbs Creek and shows the proportion of samples that meet the E. coli guideline of 100 CFU/100 ml. The monthly geometric mean with respect to the guideline for the 2006-2017 period is shown in Figure 24 and distribution of sampled counts is shown in Figure 25.

Table 12 Summary of E. coli results for Jebbs Creek, 2006-2017
E. coli 2006-2017
SiteGeometric Mean (CFU/100ml)Below GuidelineNo. Samples
JEB-013481%70

E. coli results at site JEB-01 indicate bacterial counts are typically below (81 percent) the E. coli guideline, similarly the count at geometric mean is 34 CFU/100ml (Table 12).  E. coli counts are typically highest during the summer months as warmer temperatures are needed for bacteria to survive (Figure 24). Results have varied for each sampled year, but no trend was observed across the 2006-2017 period (Figure 25).

Figure 24 Geometric mean of monthly E. coli counts in Jebbs Creek, 2006-2017
Figure 25  Distribution of E. coli counts in Jebbs Creek, 2006-2017
 
Summary of Jebbs Creek Bacterial Contamination

Results indicate that bacterial contamination is not a concern in Jebbs Creek. The count at the geometric mean is below the PWQO for both monitoring periods and a limited number of counts exceeding the guideline have been observed. The elevated samples that do occur are most likely due to wildlife and can be considered natural variability in the aquatic ecosystem.  However, good stewardship practices should be maintained throughout the drainage area to protect both Jebbs Creek and the Tay River downstream; this includes properly maintaining septic systems, enhancing shoreline buffers and restricting livestock access; all are actions that can help to protect water quality conditions in Jebbs Creek.


[1] No Ontario guideline for TKN is presently available; however, waters not influenced by excessive organic inputs typically range from 0.100 to 0.500 mg/l, Environment Canada (1979) Water Quality Sourcebook, A Guide to Water Quality Parameters, Inland Waters Directorate, Water Quality Branch, Ottawa, Canada.

[2] Trends in the data were assessed using the Mann-Kendall trend test and Sens slope statistic.

[3] Comparisons of means was done using the two sample t-test, variances were assessed using the F test. Permutation tests of difference in means and the Wilcoxon Rank Sum on differences in medians was also used to evaluate the data sets.

[4] A type of mean or average, which indicates the central tendency or typical value of a set of numbers by using the product of their values (as opposed to the arithmetic mean which uses their sum). It is often used to summarise a variable that varies over several orders of magnitude, such as E. coli counts.

[5] One result from June 8, 2009 of 0.091 mg/l has been removed from the dataset, as this result differs significantly from the dataset. It is likely an outlier and may have been influenced by a contaminated sample, sample error or analytical error.

3.0  Otty Lake Catchment: Riparian Conditions

The RVCA Stream Characterization Program evaluated 3.9 km of Jebbs Creek in 2016.  A total of 39 stream survey assessments were completed in the month of June and the first week of July. 

During the summer and fall of 2016, the Rideau Valley watershed experienced periods of severe drought. Precipitation levels were measured at less than 40% of the long-term average, as the water supply was unable to meet local demand. The lack of rainfall affected the success and function of farm crops, municipal and private wells, lawns and gardens, navigation and ultimately the health of our lakes, rivers and streams.

Low water conditions were readily observed throughout the watershed, as many of the streams were highly fragmented or completely dry (see photo below). Aquatic species such as amphibians, fish and  benthic invertebrates were affected, as suitable habitat may have been limited.

Fragmentation of habitat was observed along Jebbs Creek at the Perth Wildlife Reserve during the summer and fall of 2016
 

3.1 Jebbs Creek Overbank Zone

3.1.1 Riparian Buffer Evaluation

The quality of the riparian area increases with the width, complexity and linear extent of its vegetation along a stream or creek. A complex riparian community consists of diverse plant species native to the site, with multiple age-classes providing vertical structural diversity along a watercourse.

Here is a list of watershed benefits from a healthy riparian buffer zone:

  • Reduces the amount of pollutants that reach the stream from surface runoff
  • Helps reduce and mitigate erosion
  • Provides a microclimate that is cooler during the summer months providing cooler water for aquatic organisms
  • Provides large wood structure from fallen trees and limbs that form instream cover, create pools, stabilize the streambed, and provide habitat for aquatic organisms
  • Provides organic material for stream biota that, among other functions, is the base of the food chain in lower order streams
  • Provides habitat for terrestrial insects that drop in the stream and become food for fish and travel corridors for other terrestrial animals
  • Dissipates energy during flood events
  • Often provides the only refuge areas for fish during out-of-bank flows (behind trees, stumps, and logs)

Figure 26 demonstrates the buffer conditions of the left and right banks separately.  Jebbs Creek had a buffer of greater than 30 meters along 91 percent of the right bank and 97 percent of the left bank.

Figure XX Riparian Buffer Evaluation along Jebbs Creek
Figure 26 Riparian Buffer Evaluation along Jebbs Creek 
 

3.1.2 Riparian Buffer Alterations

Alterations within the riparian buffer were assessed within three distinct shoreline zones (0-5m, 5-15m, 15-30m), and evaluated based on the dominant vegetative community and/or land cover type (Figure 27). The riparian buffer zone along Jebbs Creek was found to be dominated by forest and wetland conditions along the riparian corridor.

Figure 27 Riparian buffer alterations along Jebbs Creek
 

3.1.3 Adjacent Land Use

The RVCA’s Stream Characterization Program identifies seven different land uses along Jebbs Creek (Figure 28). Surrounding land use is considered from the beginning to end of the survey section (100m) and up to 100m on each side of the river. Land use outside of this area is not considered for the surveys but is nonetheless part of the subwatershed and will influence the creek. Natural areas made up 96 percent of the stream, characterised by forest, scrubland, meadow and wetland. Wetland habitat was dominant in the adjacent lands along Jebbs Creek at 84 percent of the surveyed sections. The remaining land use consisted of industrial/commercial, residential and other in the form of hydro infrastructure.

Figure 28 Land Use along Jebbs Creek
 
 

3.2 Jebbs Creek Shoreline Zone

3.2.1 Instream Erosion

Stream erosion is the process by which water erodes and transports sediments, resulting in dynamic flows and diverse habitat conditions.  Excessive erosion can result in drastic environmental changes, as habitat conditions, water quality and aquatic life are all negatively affected.  Bank stability was assessed as the overall extent of each section with “unstable” shoreline conditions.  These conditions are defined by the presence of significant exposed soils/roots, minimal bank vegetation, severe undercutting, slumping or scour and potential failed erosion measures. The majority of Jebbs Creek had low levels of erosion with the exception of one location along the system which had moderate levels of erosion near the confluence with the Tay marsh (Figure 29).

Figure 29 Stream erosion levels along Jebbs Creek
 
 

3.2.2 Undercut Stream Banks

Stream bank undercuts can provide excellent cover habitat for aquatic life, however excessive levels can be an indication of unstable shoreline conditions.  Bank undercut was assessed as the overall extent of each surveyed section with overhanging bank cover present. Figure 30 shows that Jebbs Creek had low levels of undercut banks along the majority of the system which is typical for systems that are dominated by riverine wetland habitat along the shoreline. 

Figure 30 Undercut stream banks along Jebbs Creek
 
 

3.2.3 Stream Shading

Grasses, shrubs and trees all contribute towards shading a stream. Shade is important in moderating stream temperature, contributing to food supply and helping with nutrient reduction within a stream.  Stream cover is assessed as the total coverage area in each section that is shaded by overhanging trees/grasses and tree canopy, at greater than one metre above the water surface.  Figure 31 shows highly variable conditions of none to high levels of stream shading along Jebbs Creek.

Figure 31 Stream shading along Jebbs Creek
 

3.2.4 Instream Wood Structure

Forested shorelines provide essential complex habitat through the perpetual process of shoreline trees falling into the water.  This continuous recruitment of trees creates a wood-based physical structure in the littoral zone that is common on natural systems.  Insects, fish, amphibians, birds, and other animals have also evolved with this abundance of near shore wood and it is essential to their life cycles. With increased development along many waterways, forested lakeshores have been altered and wood-based physical structure in many waterways has been reduced. It is important to restore this essential habitat to aquatic ecosystems.

Shoreline Protection

  • Protects shorelines by providing a barrier from wind and wave erosion
  • Reduces sedimentation of the water caused by shoreline slumping due to bank erosion
  • Allows detritus to collect and settle on the lake or creek bed providing the substrate structure required for native aquatic vegetation to establish and outcompete invasive species
 

Food Source

  • Wood complexes are an important food source for invertebrates 
  • Small fish feed on the abundance of invertebrates that are found around these structures
  • Larger fish, waterfowl and shorebirds all benefit from the abundance of invertebrates and small fish feeding around woody structures in the littoral zone 

Cover

  • Cover from predators is essential for many fish and animals to successfully complete their life cycle
  • The nooks and crannies of wood complexes offer critters safety from predators while at the same time concentrating prey to make predators more efficient
  • Wood provides the structure on which many species must lay or attach their eggs, therefore these complexes provide quality spawning and nesting habitat

Diversity

  • Wood complexes in the littoral zone provide unique edge habitat along the shoreline
  • Edge habitats contain more species diversity and higher concentrations of species than the adjoining habitats themselves will have

Figure 32 shows that the majority of Jebbs Creek had low to moderate levels of instream wood structure in the form of branches and trees along the system.

Figure 32 Instream wood structure along Jebbs Creek
 
 

3.2.5 Overhanging Wood Structure

Trees and branches that are less than one meter from the surface of the water are defined as overhanging.  Overhanging wood structure provide a food source, nutrients and shade which helps to moderate instream water temperatures. Figure 33 shows the system is dominated by low to moderate levels of overhanging branches and trees along Jebbs Creek.

Figure 33 Overhanging trees and branches along Jebbs Creek
 

3.2.6 Anthropogenic Alterations

Stream alterations are classified based on specific functional criteria associated with the flow conditions, the riparian buffer and potential human influences.  Figure 34 shows 74 percent of Jebbs Creek remains “unaltered” with no anthropogenic alterations.   Eighteen percent of Jebbs Creek was classified as natural with minor anthropogenic changes, while eight percent was considered altered.  The alterations along Jebbs Creek were in the form of a road crossing and areas with reduced natural buffers.

Figure 34 Anthropogenic alterations along Jebbs Creek
 

3.3 Jebbs Creek Instream Aquatic Habitat

3.3.1 Benthic Invertebrates

Freshwater benthic invertebrates are animals without backbones that live on the stream bottom and include crustaceans such as crayfish, molluscs and immature forms of aquatic insects. Benthos represent an extremely diverse group of aquatic animals and exhibit wide ranges of responses to stressors such as organic pollutants, sediments and toxicants, which allows scientists to use them as bioindicators.  As part of the Ontario Benthic Biomonitoring Network (OBBN), the RVCA has been collecting benthic invertebrates at the Perth Wildlife Reserve site on Jebbs Creek since 2003. Monitoring data is analysed for each sample site and the results are presented using the Family Biotic Index, Family Richness and percent Ephemeroptera, Plecoptera and Trichoptera.  There were no values recorded for the Fall of 2016 due to extreme drought conditions therefore no samples could be collected.

OBBN sample location at the Perth Wildlife Reserve in the spring of 2016
 
 
Hilsenhoff Family Biotic Index

The Hilsenhoff Family Biotic Index (FBI) is an indicator of organic and nutrient pollution and provides an estimate of water quality conditions for each site using established pollution tolerance values for benthic invertebrates. FBI results for the Jebbs Creek catchment sample location at the Perth Wildlife Reserve are summarised by year from 2005 to 2016.  “Fair” to “Poor” water quality conditions were observed at the Jebbs Creek sample location (Figure 35) using a grading scheme developed by Conservation Authorities in Ontario for benthic invertebrates.   

Figure 35 Hilsenhoff Family Biotic Index at the Perth Wildlife Reserve sample location
 
Family Richness

Family Richness measures the health of the community through its diversity and increases with increasing habitat diversity suitability and healthy water quality conditions. Family Richness is equivalent to the total number of benthic invertebrate families found within a sample. The Jebbs Creek site is reported to have “Fair” family richness (Figure 36).

Figure 36 Family Richness at the Jebbs at the Perth Wildlife Reserve location
 
 
EPT

Ephemeroptera (Mayflies), Plecoptera (Stoneflies), and Trichoptera (Caddisflies) are species considered to be very sensitive to poor water quality conditions. A high abundance of these organisms is generally an indication of good water quality conditions at a sample location.  The community structure is typically dominated by species that are moderately tolerant and tolerant to poorer water quality conditions at the Jebbs Creek sample location.  As a result, the EPT indicates that the Jebbs Creek sample location is reported to have “Fair” to “Poor” water quality (Figure 37) from 2005 to 2016.

Figure 37 EPT at the Jebbs Creek at the Perth Wildlife Reserve sample location
 
Conclusion

Overall the Jebbs Creek sample location aquatic habitat conditions from a benthic invertebrate perspective is considered “Fair to Poor” from 2005 to 2016 as the samples are dominated by species that are moderately tolerant and tolerant to high organic pollution levels.

 

3.3.2 Habitat Complexity

Habitat complexity is a measure of the overall diversity of habitat types and features within a stream. Streams with high habitat complexity support a greater variety of species niches, and therefore contribute to greater diversity. Factors such as substrate, flow conditions (pools, riffles) and cover material (vegetation, wood structure, etc.) all provide crucial habitat to aquatic life.  Habitat complexity is assessed based on the presence of boulder, cobble and gravel substrates, as well as the presence of instream woody material.

Low to high habitat complexity was identified for Jebbs Creek (Figure 38). Regions with increased habitat complexity were observed in the lower and upper reaches of the system within the catchment.

Figure 38 Habitat complexity along Jebbs Creek
 

3.3.3 Instream Substrate

Diverse substrate is important for fish and benthic invertebrate habitat because some species have specific substrate requirements and for example will only reproduce on certain types of substrate.  The absence of diverse substrate types may limit the overall diversity of species within a stream. Figure 39 shows the overall presence of various substrate types observed along Jebbs Creek.  Substrate conditions were somewhat diverse along Jebbs Creek with all substrate types being recorded at various locations along the creek.  Silt was the dominant substrate type observed along Jebbs Creek which is consistent with riverine wetland habitat. Figure 40 shows the dominant substrate type observed for each section surveyed along Jebbs Creek. 

Figure 39 Instream substrate along Jebbs Creek
 
Figure 40 shows the dominant substrate type along Jebbs Creek
 

3.3.4 Instream Morphology

Pools and riffles are important habitat features for aquatic life.  Riffles are fast flowing areas characterised by agitation and overturn of the water surface. Riffles thereby play a crucial role in contributing to dissolved oxygen conditions and directly support spawning for some fish species.  They are also areas that support high benthic invertebrate populations which are an important food source for many aquatic species.  Pools are characterised by minimal flows, with relatively deep water and winter/summer refuge habitat for aquatic species.  Runs are moderately shallow, with unagitated surfaces of water and areas where the thalweg (deepest part of the channel) is in the centre of the channel. Figure 41 shows that Jebbs Creek is fairly uniform; 100 percent of sections recorded runs, five percent riffles and 33 percent of sections contained pool habitat. Figure 42 shows where the limited riffle habitat areas were observed along Jebbs Creek.

Figure 41 Instream morphology along Jebbs Creek
 
Figure 42 Riffle habitat locations along Jebbs Creek
 

3.3.5 Vegetation Type

Instream vegetation provides a variety of functions and is a critical component of the aquatic ecosystem.  Aquatic plants promote stream health by:

  • Providing direct riparian/instream habitat
  • Stabilising flows reducing shoreline erosion
  • Contributing to dissolved oxygen through photosynthesis
  • Maintaining temperature conditions through shading

For example emergent plants along the shoreline can provide shoreline protection from wave action and important rearing habitat for species of waterfowl.  Submerged plants provide habitat for fish to find shelter from predator fish while they feed.  Floating plants such as water lilies shade the water and can keep temperatures cool while reducing algae growth.  Floating plants were observed in 95% of sections surveyed, algae was observed in 90% of sections, narrow leaved emergents were present in 72% of the sections surveyed, while free floating plants were observed in 44% of surveyed sections.  Broad leaved emergents were observed in 44% of sections, submerged plants in 56% and robust emergents in 15% of sections surveyed.  Figure 43 depicts the plant community structure for Jebbs Creek. Figure 44 shows the dominant vegetation type observed for each section surveyed along the Jebbs Creek catchment.

Figure 43 Vegetation type along Jebbs Creek
 
Figure 44 Dominant vegetation type along Jebbs Creek
 

3.3.6 Instream Vegetation Abundance

Instream vegetation is an important factor for a healthy stream ecosystem. Vegetation helps to remove contaminants from the water, contributes oxygen to the stream, and provides habitat for fish and wildlife. Too much vegetation can also be detrimental. Figure 45 demonstrates that the Jebbs Creek reach had normal to common levels of vegetation recorded at 36 and 90 percent of stream surveys.  Extensive levels of vegetation were observed along 64 percent of the surveyed sections and were consistent with areas dominated by the invasive plant known as European Frogbit.

Figure 45 Instream vegetation abundance along Jebbs Creek
 

3.3.7 Invasive Species

Invasive species can have major implications on streams and species diversity. Invasive species are one of the largest threats to ecosystems throughout Ontario and can out compete native species, having negative effects on local wildlife, fish and plant populations. One hundred percent of the sections surveyed along Jebbs Creek reach contained invasive species. The invasive species observed in Jebbs Creek were European frogbit and banded mystery snail.  Invasive species abundance (i.e. the number of observed invasive species per section) was assessed to determine the potential range/vector of many of these species (Figure 46).

Figure 46 Invasive species abundance along Jebbs Creek
 
 

3.3.8 Water Chemistry

During the stream characterization survey, a YSI probe is used to collect water chemistry information.  Dissolved oxygen (DO), specific conductivity (SPC) and pH are measured at the start and end of each section. 

3.3.8.1 Dissolved Oxygen

Dissolved oxygen is a measure of the amount of oxygen dissolved in water. The Canadian Environmental Quality Guidelines of the Canadian Council of Ministers of the Environment (CCME) suggest that for the protection of aquatic life the lowest acceptable dissolved oxygen concentration should be 6 mg/L for warmwater biota and 9.5 mg/L for coldwater biota (CCME, 1999).  Figure 47 shows that the dissolved oxygen in Jebbs Creek supports warmwater and in certain locations coldwater biota along the system.  The average dissolved oxygen levels observed within Jebbs Creek was 9.5mg/L which is well above the recommended levels for warmwater biota. 

Figure 47 Dissolved oxygen ranges in Jebbs Creek
 

3.3.8.2 Conductivity

Conductivity in streams is primarily influenced by the geology of the surrounding environment, but can vary drastically as a function of surface water runoff. Currently there are no CCME guideline standards for stream conductivity; however readings which are outside the normal range observed within the system are often an indication of unmitigated discharge and/or stormwater input. The average conductivity observed within the main stem of Jebbs Creek was 262.5 µs/cm. Figure 48 shows the conductivity readings for Jebbs Creek.

Figure 48 Specific conductivity ranges in Jebbs Creek
 
 

3.3.8.3 pH

Based on the PWQO for pH, a range of 6.5 to 8.5 should be maintained for the protection of aquatic life. Average pH values for Jebbs Creek averaged 7.94 thereby meeting the provincial standard (Figure 49).

Figure 49 pH ranges in Jebbs Creek
 

3.3.8.4 Oxygen Saturation (%)

Oxygen saturation is measured as the ratio of dissolved oxygen relative to the maximum amount of oxygen that will dissolve based on the temperature and atmospheric pressure. Well oxygenated water will stabilise at or above 100% saturation, however the presence of decaying matter/pollutants can drastically reduce these levels. Oxygen input through photosynthesis has the potential to increase saturation above 100% to a maximum of 500%, depending on the productivity level of the environment. In order to represent the relationship between concentration and saturation, the measured values have been summarised into 6 classes:

Dissolved oxygen conditions in Jebbs Creek varied along the system for both warm and coolwater species (Figure 50).

Figure 50 A bivariate assessment of dissolved oxygen concentration (mg/L) and saturation (%) in Jebbs Creek
 

3.3.8.5 Specific Conductivity Assessment

Specific conductivity (SPC) is a standardised measure of electrical conductance, collected at or corrected to a water temperature of 25⁰C. SPC is directly related to the concentration of ions in water, and is commonly influenced by the presence of dissolved salts, alkalis, chlorides, sulfides and carbonate compounds. The higher the concentration of these compounds, the higher the conductivity. Common sources of elevated conductivity include storm water, agricultural inputs and commercial/industrial effluents.

In order to summarise the conditions observed, SPC levels were evaluated as either normal, moderately elevated or highly elevated. These categories correspond directly to the degree of variation (i.e. standard deviation) at each site relative to the average across the system.

Normal levels were maintained along the majority of Jebbs Creek, however there were moderately elevated areas in the middle reaches (Figure 51).

Figure 51 Relative specific conductivity levels along Jebbs Creek
 

3.3.9 Thermal Regime

Many factors can influence fluctuations in stream temperature, including springs, tributaries, precipitation runoff, discharge pipes and stream shading from riparian vegetation. Water temperature is used along with the maximum air temperature (using the Stoneman and Jones method) to classify a watercourse as either warm water, cool water or cold water.  Figure 52 shows where the thermal sampling site was located on Jebbs Creek.  Analysis of the data collected indicates that Jebbs Creek is classified as a warm water system (Figure 53).  

Figure 52 Temperature logger location on Jebbs Creek
 
Figure XX Temperature logger data for the site on Jebbs Creek
Figure 53 Temperature logger data for the site on Jebbs Creek 
 

Each point on the graph represents a temperature that meets the following criteria:

  • Sampling dates between July 1st and September 7th
  • Sampling date is preceded by two consecutive days above 24.5 °C, with no rain
  • Water temperatures are collected at 4pm
  • Air temperature is recorded as the max temperature for that day
 

3.3.10 Groundwater

Groundwater discharge areas can influence stream temperature, contribute nutrients, and provide important stream habitat for fish and other biota. During stream surveys, indicators of groundwater discharge are noted when observed. Indicators include: springs/seeps, watercress, iron staining, significant temperature change and rainbow mineral film.  Figure 54 shows areas where one or more of the above groundwater indicators were observed during stream surveys and headwater drainage feature assessments. 

Figure 54 Groundwater indicators observed in the Otty Lake catchment
 
 

3.3.11 Fish Community

The Otty Lake catchment is classified as a mixed community of warm and cool water recreational and baitfish fishery with 19 species observed. Figure 55 shows the historical and 2016 fish sampling locations in the catchment. 

Figure 55 Otty Lake catchment fish community
 
 

Table 13 is a list of species observed in the watershed historically and during the 2016 sampling effort.

Table 13 Fish species observed in the Otty Lake catchment
Fish SpeciesScientific NameFish codeHistorical2016
banded killifishFundulus diaphanusBaKilX
bluegillLepomis macrochirusBluegXX
bluntnose minnowPimephales notatusBnMinX
brook sticklebackCulaea inconstansBrStiX
brown bullheadAmeiurus nebulosusBrBulXX
burbotLota lotaBurboX
central mudminnowUmbra limiCeMudX
common shinerLuxilus cornutusCoShiXX
creek chubSemotilus atromaculatusCrChuX
etheostoma sp.etheostoma sp.EthSpX
fallfishSemotilus corporalisFallfXX
golden shinerNotemigonus crysoleucasGoShiXX
greater redhorseMoxostoma valenciennesiGrRedX
largemouth bassMicropterus salmoidesLmBasX
northern pikeEsox luciusNoPikX
pumpkinseedLepomis gibbosusPumpkXX
rock bassAmbloplites rupestrisRoBasXX
smallmouth bassMicropterus dolomieuSmBasX
white suckerCatostomus commersoniiWhSucXX
yellow bullheadAmeiurus natalisYeBulX
TOTAL Species199
RVCA staff setting a fyke net at County Road 1 on Jebbs Creek in May 2016
 
Greater redhorse (Moxostoma valenciennesi) captured and released while fyke netting on Jebbs Creek adjacent to the Perth Wildlife Reserve
 

3.3.12 Migratory Obstructions

Migratory obstructions represent limitations to fish dispersal within a system and may restrict access to important spawning and rearing habitat. Migratory obstructions can be natural or manmade, and they can be permanent or seasonal. Figure 56 shows the migratory obstructions observed for the Otty Lake catchment.  

Figure 56 Migratory obstructions in the Otty Lake catchment
 

3.3.13 Beaver Dams

Overall beaver dams create natural changes in the environment. Some of the benefits include providing habitat for wildlife, flood control, and silt retention. Additional benefits come from bacterial decomposition of woody material used in the dams which removes excess nutrient and toxins. Beaver dams can also result in flooding of agricultural fields and may also be considered potential barriers to fish migration.  Figure 57 shows the types of beaver dams that were identified on the surveyed portions of Jebbs Creek in 2016.

Figure 57 Beaver Dam locations in the Otty Lake catchment
 
 

3.4 Headwater Drainage Feature Assessment

3.4.1 Headwaters Sampling Locations

The RVCA Stream Characterization program assessed Headwater Drainage Features for the Otty Lake catchment in 2017. This protocol measures zero, first and second order headwater drainage features (HDF).  It is a rapid assessment method characterizing the amount of water, sediment transport, and storage capacity within headwater drainage features (HDF). RVCA is working with other Conservation Authorities and the Ministry of Natural Resources and Forestry to implement the protocol with the goal of providing standard datasets to support science development and monitoring of headwater drainage features.  An HDF is a depression in the land that conveys surface flow. Additionally, this module provides a means of characterizing the connectivity, form and unique features associated with each HDF (OSAP Protocol, 2013).   In 2017 the program sampled 32 sites at road crossings in the Otty Lake catchment area (Figure 58).  

Figure 58 Location of the headwater sampling sites in the Otty Lake catchment
 
 

3.4.2 Headwater Feature Type

The headwater sampling protocol assesses the feature type in order to understand the function of each feature.  The evaluation includes the following classifications: defined natural channel, channelized or constrained, multi-thread, no defined feature, tiled, wetland, swale, roadside ditch and pond outlet.  By assessing the values associated with the headwater drainage features in the catchment area we can understand the ecosystem services that they provide to the watershed in the form of hydrology, sediment transport, and aquatic and terrestrial functions.  The headwater drainage features in the Otty Lake catchment are primarily classified as wetland and natural features.  Figure 59 shows the feature type of the primary feature at the sampling locations.

Figure 59 Headwater feature types in the Otty Lake catchment
 
A spring photo of the headwater sample site on Mackler Side Road 
 
A summer photo of the headwater sample site on Mackler Side Road
 
 

3.4.3 Headwater Feature Flow

The observed flow condition within headwater drainage features can be highly variable depending on timing relative to the spring freshet, recent rainfall, soil moisture, etc.  Flow conditions are assessed in the spring and in the summer to determine if features are perennial and flow year round, if they are intermittent and dry up during the summer months or if they are ephemeral systems that do not flow regularly and generally respond to specific rainstorm events or snowmelt.  Flow conditions in headwater systems can change from year to year depending on local precipitation patterns.  Figure 60 shows the observed flow condition at the sampling locations in the Otty Lake catchment in 2017.

Figure 60 Headwater feature flow conditions in the Otty Lake catchment
 
 

3.4.4 Feature Channel Modifications

Channel modifications were assessed at each headwater drainage feature sampling location.  Modifications include channelization, dredging, hardening and realignments.  Figure 61 shows the channel modifications observed at the sampling locations for the Otty Lake.  The majority of the headwater features had no modifications observed at the sample locations.

Figure 61 Headwater feature channel modifications in the Otty Lake catchment
 
 

3.4.5 Headwater Feature Vegetation

Headwater feature vegetation evaluates the type of vegetation that is found within the drainage feature. The type of vegetation within the channel influences the aquatic and terrestrial ecosystem values that the feature provides.  For some types of headwater features the vegetation within the feature plays a very important role in flow and sediment movement and provides fish and wildlife habitat.  The following classifications are evaluated no vegetation, lawn, wetland, meadow, scrubland and forest.  The features assessed were classified as being dominated by wetland and meadow.  Figure 62 depicts the dominant vegetation observed at the sampled headwater sites in the Otty Lake catchment.

Figure 62 Headwater feature vegetation types in the Otty Lake catchment
 
 

3.4.6 Headwater Feature Riparian Vegetation

Headwater riparian vegetation evaluates the type of vegetation that is found along the adjacent lands of a headwater drainage feature.  The type of vegetation within the riparian corridor influences the aquatic and terrestrial ecosystem values that the feature provides to the watershed.  The sample locations were dominated by natural vegetation.  Figure 63 depicts the type of riparian vegetation observed at the sampled headwater sites in the Otty Lake catchment.

Figure 63 Headwater feature riparian vegetation types in the Otty Lake catchment
 
 

3.4.7 Headwater Feature Sediment Deposition

Assessing the amount of recent sediment deposited in a channel provides an index of the degree to which the feature could be transporting sediment to downstream reaches (OSAP, 2013).  Evidence of excessive sediment deposition might indicate the requirement to follow up with more detailed targeted assessments upstream of the site location to identify potential best management practices to be implemented.  Conditions ranged from no deposition observed to extensive deposition recorded.  Figure 64 depicts the degree of sediment deposition observed at the sampled headwater sites in the Otty Lake catchment.

Figure 64 Headwater feature sediment deposition in the Otty Lake catchment
 
 

3.4.8 Headwater Feature Upstream Roughness

Feature roughness will provide a measure of the amount of materials within the bankfull channel that could slow down the velocity of water flowing within the headwater feature (OSAP, 2013).  Materials on the channel bottom that provide roughness include vegetation, woody debris and boulders/cobble substrates.  Roughness can provide benefits in mitigating downstream erosion on the headwater drainage feature and the receiving watercourse by reducing velocities.  Roughness also provides important habitat conditions to aquatic organisms. Figure 65 shows the feature roughness conditions at the sampling location in the Otty Lake catchment.

Figure 65 Headwater feature roughness in the Otty Lake catchment
 

4.0 Otty Lake Catchment: Land Cover

Land cover and any change in coverage that has occurred over a six year period is summarised for the Otty Lake catchment using spatially continuous vector data representing the catchment during the spring of 2008 and 2014. This dataset was developed by the RVCA through heads-up digitization of 20cm DRAPE ortho-imagery at a 1:4000 scale and details the surrounding landscape using 10 land cover classes.

4.1 Otty Lake Catchment Change

As shown in Table 14 and Figure 1 (see the Introduction section of this report), the dominant land cover type in 2014 is woodland.

Table 14 Land cover in the Otty Lake catchment (2008 vs. 2014)
Land Cover20082014Change - 2008 to 2014
AreaAreaArea
HaPercentHaPercentHaPercent
Woodland*214041213341-70
Wetland **11122111122100
>Evaluated(159)(3)(159)(3)(0)(0)
>Unevaluated(953)(18)(953)(18)(0)(0)
Water766147661400
Crop and Pasture6961369313-30
Settlement25252635110
Transportation1673167300
Meadow-Thicket15231513-10
* Does not include treed swamps ** Includes treed swamps
 

From 2008 to 2014, there was an overall change of 11 hectares (from one land cover class to another). Most of the change in the Otty Lake catchment is a result of the conversion of crop and pastureland, meadow-thicket and woodland to settlement (Figure 66).

LandCoverChangeNewTay-RiverOtty-Lake---Jebbs-Creek-001-001
Figure 66 Land cover change in the Otty Lake catchment (2008 to 2014)
 

Table 15 provides a detailed breakdown of all land cover change that has taken place in the Otty Lake catchment between 2008 and 2014.

Table 15 Land cover change in the Otty Lake catchment (2008 to 2014)
Land CoverChange - 2008 to 2014
Area
Ha.Percent
Woodland to Settlement6.962.5
Crop and Pasture to Settlement327.6
Meadow-Thicket to Settlement0.98
Woodland to Transportation0.11.3
Woodland to Crop and Pasture0.10.6

4.2 Woodland Cover

In the Environment Canada Guideline (Third Edition) entitled “How Much Habitat Is Enough?” (hereafter referred to as the “Guideline”) the opening narrative under the Forest Habitat Guidelines section states that prior to European settlement, forest was the predominant habitat in the Mixedwood Plains ecozone. The remnants of this once vast forest now exist in a fragmented state in many areas (including the Rideau Valley watershed) with woodland patches of various sizes distributed across the settled landscape along with higher levels of forest cover associated with features such as the Frontenac Axis (within the on-Shield areas of the Rideau Lakes and Tay River subwatersheds). The forest legacy, in terms of the many types of wildlife species found, overall species richness, ecological functions provided and ecosystem complexity is still evident in the patches and regional forest matrices (found in the Tay River subwatershed and elsewhere in the Rideau Valley watershed). These ecological features are in addition to other influences which forests have on water quality and stream hydrology including reducing soil erosion, producing oxygen, storing carbon along with many other ecological services that are essential not only for wildlife but for human well-being.

The Guideline also notes that forests provide a great many habitat niches that are in turn occupied by a great diversity of plant and animal species. They provide food, water and shelter for these species - whether they are breeding and resident locally or using forest cover to help them move across the landscape. This diversity of species includes many that are considered to be species at risk. Furthermore, from a wildlife perspective, there is increasing evidence that the total forest cover in a given area is a major predictor of the persistence and size of bird populations, and it is possible or perhaps likely that this pattern extends to other flora and fauna groups. The overall effect of a decrease in forest cover on birds in fragmented landscapes is that certain species disappear and many of the remaining ones become rare, or fail to reproduce, while species adapted to more open and successional habitats, as well as those that are more tolerant to human-induced disturbances in general, are able to persist and in some cases thrive. Species with specialised habitat requirements are most likely to be adversely affected. The overall pattern of distribution of forest cover, the shape, area and juxtaposition of remaining forest patches and the quality of forest cover also play major roles in determining how valuable forests will be to wildlife and people alike.

The current science generally supports minimum forest habitat requirements between 30 and 50 percent, with some limited evidence that the upper limit may be even higher, depending on the organism/species phenomenon under investigation or land-use/resource management planning regime being considered/used.

As shown in Figure 67, 41 percent of the Otty Lake catchment contains 2133 hectares of upland forest and 42 hectares of lowland forest (treed swamps) versus the 47 percent of woodland cover in the Tay River subwatershed. This is greater than the 30 percent of forest cover that is identified as the minimum threshold required to sustain forest birds according to the Guideline and which may only support less than one half of potential species richness and marginally healthy aquatic systems. When forest cover drops below 30 percent, forest birds tend to disappear as breeders across the landscape.

InteriorForestTay-RiverOtty-Lake---Jebbs-Creek-001-001
Figure 67 Woodland cover and forest interior in the Otty Lake catchment (2014)
 

4.2.1 Woodland (Patch) Size

According to the Ministry of Natural Resources’ Natural Heritage Reference Manual (Second Edition), larger woodlands are more likely to contain a greater diversity of plant and animal species and communities than smaller woodlands and have a greater relative importance for mobile animal species such as forest birds.

Bigger forests often provide a different type of habitat. Many forest birds breed far more successfully in larger forests than they do in smaller woodlots and some rely heavily on forest interior conditions. Populations are often healthier in regions with more forest cover and where forest fragments are grouped closely together or connected by corridors of natural habitat. Small forests support small numbers of wildlife. Some species are “area-sensitive” and tend not to inhabit small woodlands, regardless of forest interior conditions. Fragmented habitat also isolates local populations, especially small mammals, amphibians and reptiles with limited mobility. This reduces the healthy mixing of genetic traits that helps populations survive over the long run (Conserving the Forest Interior. Ontario Extension Notes, 2000).

The Environment Canada Guideline also notes that for forest plants that do not disperse broadly or quickly, preservation of some relatively undisturbed large forest patches is needed to sustain them because of their restricted dispersal abilities and specialised habitat requirements and to ensure continued seed or propagation sources for restored or regenerating areas nearby.

The Natural Heritage Reference Manual continues by stating that a larger size also allows woodlands to support more resilient nutrient cycles and food webs and to be big enough to permit different and important successional stages to co-exist. Small, isolated woodlands are more susceptible to the effects of blowdown, drought, disease, insect infestations, and invasions by predators and non-indigenous plants. It is also known that the viability of woodland wildlife depends not only on the characteristics of the woodland in which they reside, but also on the characteristics of the surrounding landscape where the woodland is situated. Additionally, the percentage of forest cover in the surrounding landscape, the presence of ecological barriers such as roads, the ability of various species to cross the matrix surrounding the woodland and the proximity of adjacent habitats interact with woodland size in influencing the species assemblage within a woodland.

In the Otty Lake catchment (in 2014), one hundred and forty-eight (52 percent) of the 285 woodland patches are very small, being less than one hectare in size. Another 121 (42 percent) of the woodland patches ranging from one to less than 20 hectares in size tend to be dominated by edge-tolerant bird species. The remaining 16 (six percent of) woodland patches range between 22 and 709 hectares in size. Thirteen of these patches contain woodland between 20 and 100 hectares and may support a few area-sensitive species and some edge intolerant species, but will be dominated by edge tolerant species.

Conversely, three (one percent) of the 285 woodland patches in the drainage area exceed the 100 plus hectare size needed to support most forest dependent, area sensitive birds and are large enough to support approximately 60 percent of edge-intolerant species. One patch tops 200 hectares, which according to the Environment Canada Guideline will support 80 percent of edge-intolerant forest bird species (including most area sensitive species) that prefer interior forest habitat conditions.

Table 16 presents a comparison of woodland patch size in 2008 and 2014 along with any changes that have occurred over that time. A decrease (of seven hectares) has been observed in the overall woodland patch area between the two reporting periods with most change occurring in the 1 to 20 woodland patch size class range.

Table 16 Woodland patches in the Otty Lake catchment (2008 and 2014)
Woodland Patch Size Range (ha)Woodland* PatchesPatch Change
200820142008 to 2014
NumberAreaNumberAreaNumberArea
CountPercent HaPercentCountPercent HaPercentCountHa
Less than 1 142515631485257361
1 to 2012243631291214262529-1-6
20 to 50114384171143841800
50 to 10021172821172800
100 to 2002122810212281000
Greater than 2001<1711331<1709320-2
Totals280100218210028510021751005-7
*Includes treed swamps
 

4.2.2 Woodland (Forest) Interior Habitat

The forest interior is habitat deep within woodlands. It is a sheltered, secluded environment away from the influence of forest edges and open habitats. Some people call it the “core” or the “heart” of a woodland. The presence of forest interior is a good sign of woodland health, and is directly related to the woodland’s size and shape. Large woodlands with round or square outlines have the greatest amount of forest interior. Small, narrow woodlands may have no forest interior conditions at all. Forest interior habitat is a remnant natural environment, reminiscent of the extensive, continuous forests of the past. This increasingly rare forest habitat is now a refuge for certain forest-dependent wildlife; they simply must have it to survive and thrive in a fragmented forest landscape (Conserving the Forest Interior. Ontario Extension Notes, 2000).

The Natural Heritage Reference Manual states that woodland interior habitat is usually defined as habitat more than 100 metres from the edge of the woodland and provides for relative seclusion from outside influences along with a moister, more sheltered and productive forest habitat for certain area sensitive species. Woodlands with interior habitat have centres that are more clearly buffered against the edge effects of agricultural activities or more harmful urban activities than those without.

In the Otty Lake catchment (in 2014), the 285 woodland patches contain 26 forest interior patches (Figure 67) that occupy three percent (147 ha.) of the catchment land area (which is less than the five percent of interior forest in the Tay River Subwatershed). This is below the ten percent figure referred to in the Environment Canada Guideline that is considered to be the minimum threshold for supporting edge intolerant bird species and other forest dwelling species in the landscape.

Most patches (23) have less than 10 hectares of interior forest, fifteen of which have small areas of interior forest habitat less than one hectare in size. The remaining three patches contain interior forest between 11 and 90 hectares in area. Between 2008 and 2014, there has been a small change in the number of woodland patches containing interior habitat with an overall loss of four hectares in the catchment (Table 17).

Table 17 Woodland interior in the Otty Lake catchment (2008 and 2014)
Woodland Interior Habitat Size Range (ha)Woodland InteriorInterior Change
200820142008 to 2014
NumberAreaNumberAreaNumberArea
CountPercentHaPercentCountPercent HaPercentCountHa
Less than 1 15563215583200
1 to 1093328198302517-1-3
10 to 3027291928292000
50 to 1001491601490610-1
Totals2710015110026100147100-1-4
 

4.3 Wetland Cover

Wetlands are habitats forming the interface between aquatic and terrestrial systems. They are among the most productive and biologically diverse habitats on the planet. By the 1980s, according to the Natural Heritage Reference Manual, 68 percent of the original wetlands south of the Precambrian Shield in Ontario had been lost through encroachment, land clearance, drainage and filling.

Wetlands perform a number of important ecological and hydrological functions and provide an array of social and economic benefits that society values. Maintaining wetland cover in a watershed provides many ecological, economic, hydrological and social benefits that are listed in the Reference Manual and which may include:

  • contributing to the stabilisation of shorelines and to the reduction of erosion damage through the mitigation of water flow and soil binding by plant roots
  • mitigating surface water flow by storing water during periods of peak flow (such as spring snowmelt and heavy rainfall events) and releasing water during periods of low flow (this mitigation of water flow also contributes to a reduction of flood damage)
  • contributing to an improved water quality through the trapping of sediments, the removal and/or retention of excess nutrients, the immobilization and/or degradation of contaminants and the removal of bacteria
  • providing renewable harvesting of timber, fuel wood, fish, wildlife and wild rice
  • contributing to a stable, long-term water supply in areas of groundwater recharge and discharge
  • providing a high diversity of habitats that support a wide variety of plants and animals
  • acting as “carbon sinks” making a significant contribution to carbon storage
  • providing opportunities for recreation, education, research and tourism

Historically, the overall wetland coverage within the Great Lakes basin exceeded 10 percent, but there was significant variability among watersheds and jurisdictions, as stated in the Environment Canada Guideline. In the Rideau Valley Watershed, it has been estimated that pre-settlement wetland cover averaged 35 percent using information provided by Ducks Unlimited Canada (2010) versus the 21 percent of wetland cover existing in 2014, derived from DRAPE imagery analysis.

WetlandChangeTay-RiverOtty-Lake---Jebbs-Creek-001-001
Figure 68 Wetland cover in the Otty Lake catchment (Historic to 2014)
 

This decline in wetland cover is also evident in the Otty Lake catchment (as seen in Figure 68 and summarised in Table 18), where wetland was reported to cover 31 percent of the area prior to settlement, as compared to 21 percent in 2014. This represents a 31 percent loss of historic wetland cover. To maintain critical hydrological, ecological functions along with related recreational and economic benefits provided by these wetland habitats in the catchment, a “no net loss” of currently existing wetlands should be employed to ensure the continued provision of tangible benefits accruing from them to landowners and surrounding communities.

 
Table 18 Wetland cover in the Otty Lake catchment (Historic to 2014)
Wetland Cover Pre-settlement20082014Change - Historic to 2014
Area  Area  Area  Area  
Ha Percent Ha Percent Ha Percent Ha Percent 
Otty Lake161631111221111221-504-31
Tay Rivern/an/a15280191533019n/an/a
Rideau Valley13411535n/an/a8207621-52039-39

4.4 Shoreline Cover

The riparian or shoreline zone is that special area where the land meets the water. Well-vegetated shorelines are critically important in protecting water quality and creating healthy aquatic habitats, lakes and rivers. Natural shorelines intercept sediments and contaminants that could impact water quality conditions and harm fish habitat in streams. Well established buffers protect the banks against erosion, improve habitat for fish by shading and cooling the water and provide protection for birds and other wildlife that feed and rear young near water. A recommended target (from the Environment Canada Guideline) is to maintain a minimum 30 metre wide vegetated buffer along at least 75 percent of the length of both sides of rivers, creeks and streams.

Figure 69 shows the extent of the ‘Natural’ vegetated riparian zone (predominantly wetland/woodland features) and ‘Other’ anthropogenic cover (crop/pastureland, roads/railways, settlements) along a 30-metre-wide area of land around Otty and McLaren Lake, other lakes and along both sides of the shoreline of Jebbs Creek and the many unnamed watercourses (including headwater streams) found in the Otty Lake catchment.                                              

RiparianLandCoverwWetlandTay-RiverOtty-Lake---Jebbs-Creek-001-001
Figure 69 Natural and other riparian land cover in the Otty Lake catchment (2014)
 

This analysis shows that the Otty Lake catchment riparian buffer is composed of wetland (44 percent), woodland (37 percent), crop and pastureland (eight percent), settlement (eight percent), roads (two percent) and meadow-thicket (one percent). Along the many watercourses (including headwater streams) flowing into Otty and McLaren Lake, the riparian buffer is composed of wetland (51 percent), woodland (32 percent), crop and pastureland (12 percent), roads (two percent), settlement areas (two percent) and meadow-thicket (one percent).

Around Otty Lake itself, the shoreline buffer is dominated by woodland (48 percent) and cottages, houses and camps (35 percent) with the remainder comprised of wetland (14 percent), roads (three percent) and crop and pastureland (less than one percent). The shoreline buffer around McLaren Lake is dominated by woodland (51 percent) and wetland (49 percent). Along Jebbs Creek, the riparian zone is composed of wetland (83 percent), woodland (ten percent), settlement (five percent), crop and pastureland (one percent) and roads (one percent).

Additional statistics for the Otty Lake catchment are presented in Tables 19 to 23 and show that there has been little to no change in shoreline cover from 2008 to 2014.

 
Table 19 Riparian land cover in the Otty Lake Creek catchment (2008 vs. 2014)
Riparian Land Cover20082014Change - 2008 to 2014
AreaAreaArea
Ha.Percent Ha.PercentHa.Percent
Wetland269.5943.76269.5943.760.000.00
> Unevaluated(266.25)(43.22)(266.25)(43.22)(0.00)(0.00)
> Evaluated(3.34)(0.54)(3.34)(0.54)(0.00)(0.00)
Woodland224.9636.52224.6436.47-0.32-0.05
Crop & Pasture52.208.4752.108.46-0.10-0.01
Settlement48.067.8048.487.870.420.07
Transportation14.102.2914.102.290.000.00
Meadow-Thicket7.131.167.131.160.000.00
Table 20 Riparian land cover around Otty Lake (2008 vs. 2014)
Riparian Land Cover20082014Change - 2008 to 2014
AreaAreaArea
Ha.Percent Ha.PercentHa.Percent
Woodland53.5947.9253.3847.73-0.21-0.19
Settlement38.5934.5138.8734.760.280.25
Wetland15.2213.6215.2213.620.000.00
> Unevaluated(15.22)(13.62)(15.22)(13.62)(0.00)(0.00)
Transportation3.623.243.623.240.000.00
Crop and Pasture0.790.710.720.65-0.07-0.06
Table 21 Riparian land cover around McLaren Lake (2008 vs. 2014)
Riparian Land Cover20082014Change - 2008 to 2014
AreaAreaArea
Ha.Percent Ha.PercentHa.Percent
Woodland4.8250.684.8250.680.000.00
Wetland4.6949.324.6949.320.000.00
> Unevaluated(4.69)(49.32)(4.69)(49.32)(0.00)(0.00)
 
Table 22 Riparian land cover along Jebbs Creek (2008 vs. 2014)
Riparian Land Cover20082014Change - 2008 to 2014
AreaAreaArea
Ha.Percent Ha.PercentHa.Percent
Wetland20.683.4120.683.410.000.00
> Unevaluated(20.55)(83.22)(20.55)(83.22)(0.00)(0.00)
>Evaluated(0.05)(0.19)(0.05)(0.19)(0.00)(0.00)
Woodland2.5210.222.5210.220.000.00
Settlement1.144.631.144.630.000.00
Crop & Pasture0.271.10.271.10.000.00
Transportation0.160.640.160.640.000.00
Table 23 Riparian land cover along streams in the Otty Lake Catchment (2008 vs. 2014)
Riparian Land Cover20082014Change - 2008 to 2014
AreaAreaArea
Ha.Percent Ha.PercentHa.Percent
Wetland216.0250.87216.0250.870.000.00
> Unevaluated(212.71)(50.09)(212.71)(50.09)(0.00)(0.00)
>Evaluated(3.31)(0.78)(3.31)(0.78)(0.00)(0.00)
Woodland134.3631.64134.2531.61-0.11-0.03
Crop & Pasture49.6411.6949.6211.68-0.02-0.01
Transportation9.492.249.492.240.000.00
Settlement8.281.958.421.980.140.03
Meadow-Thicket6.871.626.871.620.000.00

5.0 Otty Lake Catchment: Stewardship and Water Resources Protection

The RVCA and its partners are working to protect and enhance environmental conditions in the Tay River Watershed. Figure 70 shows the location of all stewardship projects completed in the Otty Lake catchment.

StewardshipTay-RiverOtty-Lake---Jebbs-Creek-001-001
Figure 70 Stewardship site locations in the Otty Lake catchment
 

5.1 Rural Clean Water

The Rural Clean Water Program provides technical and financial assistance to farmers and other rural landowners, to aid in the implementation of projects that protect water quality. Funding is granted to those projects that support best management practices for application in the protection and improvement of surface and ground water resources.  The program also supports climate change adaptation and low impact development projects as well as educating rural landowners about environmental stewardship of private property. Examples of supported projects include livestock exclusion fencing, controlled tile drainage, cover crops, erosion control, well related projects, and many more. For a list of eligible projects and to apply for funding, see Rural Clean Water.

In the Otty Lake catchment from 2011 to 2016, seven septic system repairs, two erosion control projects, one windbreak/buffer and one well upgrade were completed; prior to this, eight septic system repairs, eight well upgrades, three education initiatives, one manure storage facility, one milkhouse wastewater treatment project, one well decommissioning, one well replacement and one livestock fencing project had been completed. When combined, these projects are keeping 26.41 kilograms of Phosphorus out of our lakes, rivers and streams every year. Total value of all 35 projects is $325,662 with $64,241 of that amount funded through grant dollars from the RVCA.

5.2 Private Land Forestry

Forest cover and tree planting continues to be one of the most widely supported strategies to improve our environment. The many benefits of forest cover include carbon sequestration, flood mitigation and water quality improvement as well as providing wildlife habitat.

Through the RVCA's Trees for Tomorrow Program (and its predecessors), 5,800 trees were planted at two sites from 2011 to 2016; prior to this, 9,747 trees were planted at six sites. In total, 15,547 trees have been planted resulting in the reforestation of seven hectares. Total project value of all eight projects in the Otty Lake catchment is $35,523 with $25,029 of that amount coming from fundraising sources. For more information about the Program and landowner eligibility, please see the following: Tree Planting in the Rideau Valley Watershed and Trees for Tomorrow.

An additional 191 butternut trees were planted through the RVCA Butternut Recovery Program at 42 project locations, as part of efforts to introduce healthy seedlings from tolerant butternuts into various locations across Eastern Ontario.

5.3 Shoreline Naturalization

Natural shoreline buffers rich in native plants are critically important to protecting the health of our lakes, rivers and streams. Shoreline vegetation protects water quality and aquatic habitat by intercepting potentially harmful contaminants such as nutrients, pollutants and sediment, regulating water temperatures, slowing runoff and providing important fish and wildlife habitat. Natural shorelines also help improve climate change resiliency by increasing flood storage and providing protection from erosion during extreme weather events.

Though the RVCA’s Shoreline Naturalization Program, landowners (private and public property owners) have naturalized more than 2.3 km of shoreline in the Tay Watershed by planting over 10,563 native trees and shrubs at 96 sites since 2008. In the Otty Lake catchment, a total of 2,506 native trees and shrubs have been planted along 407 metres of shoreline at an average buffer width of three metres for a total project value of $19,479. A number of these projects have been undertaken in partnership with community groups. The Program has also provided the Otty Lake Association with 1,500 native tree, shrubs and wildflowers that have been distributed to property owners around Otty Lake and supported a Toronto Dominion Friends of the Environment Tree Day hosted by RVCA at the Perth Wildlife Reserve, which saw the planting of 300 trees and shrubs by local volunteers in 2016. This was followed up in 2017 by a volunteer group planting native wildflowers at the Perth Wildlife Reserve to enhance the butterfly garden for local pollinators.

5.4 Fish and Wetland Habitat Improvement

Two fish and wetland improvement projects have been completed in the Otty Lake catchment in recent years: 1) The Otty Lake Association collaborated with the Rideau Valley Conservation Authority on the Otty Lake Fish Habitat Enhancement project to improve the recreational fishery for smallmouth bass and 2) The Jebbs Creek Wetland Embayment was completed by the RVCA to enhance fish and wetland habitat along Jebbs Creek. Sixteen hundred square metres of fish habitat were created and 15 volunteers planted a mixture of 125 native trees and shrubs and trees around the new wetland feature.

5.5 Septic System Re-inspection

Septic system re-inspection is provided by the RVCA through the Mississippi Rideau Septic System Office at the request of Drummond/North Elmsley and Tay Valley Townships.

Since 2004, the service has performed 357 mandatory and voluntary septic system re-inspections on 257 properties in the Otty Lake catchment, of which, nine voluntary inspections were conducted on seven properties around McLaren and Mud Lake (with only one system needing remedial work) along with 348 mandatory re-inspectionson 250 properties around Otty Lake. Remedial/maintenance work (i.e. pump outs and baffle replacements that generally do not require a permit) was advocated for 18 of those inspections on Otty Lake, septic system replacements required at another seven properties along with more information being requested during another two inspections.

5.6 Valley, Stream, Wetland and Hazard Lands

The Otty Lake catchment covers 53 square kilometres with 3.5 square kilometres (or seven percent) of the drainage area being within the regulation limit of Ontario Regulation 174/06 (Figure 71), giving protection to wetland areas and river or stream valleys that are affected by flooding and erosion hazards.

Wetlands occupy 11 square kilometres (or 21 percent) of the catchment. Of these wetlands, two square kilometres (or 18 percent) are designated as provincially significant and included within the RVCA regulation limit. This leaves the remaining 9 sq. km (or 82 percent) of wetlands in the catchment outside the regulated area limit.

Of the 98.6 kilometres of stream in the catchment, regulation limit mapping has been plotted along 5.6 kilometres of streams (representing six percent of all streams in the catchment). Some of these regulated streams (0.6 km) flow through regulated wetlands; the remaining five kilometres of regulated streams are located outside of those wetlands. Plotting of the regulation limit on the remaining 93 kilometres (or 94 percent) of streams requires identification of flood and erosion hazards and valley systems.

Within those areas of the Otty Lake catchment subject to the regulation (limit), efforts (have been made and) continue through RVCA planning and regulations input and review to manage the impact of development (and other land management practices) in areas where “natural hazards” are associated with rivers, streams, valley lands and wetlands. For areas beyond the regulation limit, protection of the catchment’s watercourses is only provided through the “alteration to waterways” provision of the regulation.

RegulatedFeaturesTay-RiverOtty-Lake---Jebbs-Creek-001-001
Figure 71 Regulated natural features and hazards in the Otty Lake catchment
 

5.7 Vulnerable Drinking Water Areas

Mississippi-Rideau Source Water Protection Program has mapped the north boundary of the Otty Lake catchment as a Significant Groundwater Recharge Areas and all of the catchment as a Highly Vulnerable Aquifer. This means that the nature of the overburden (thin soils, fractured bedrock) does not provide a high level of protection for the underlying groundwater making the aquifer more vulnerable to contaminants released on the surface. There are no Well-Head protection Areas in the catchment.

The Mississippi-Rideau Source Protection Plan includes policies that focus on the protection of groundwater region-wide due to the fact that most of the region, which encompasses the Mississippi and Rideau watersheds, is considered Highly Vulnerable Aquifer. For detailed maps and policies that have been developed to protect drinking water sources, visit the Mississippi-Rideau Source Protection Region website.

6.0 Otty Lake Catchment: Accomplishments

Developed by the Otty Lake Association and its partners, the Otty Lake Management Plan (2008) and Five-year Review (2014) provide information on many aspects of the lake environment, as well as issues of concern and actions to be taken to maintain and improve the long-term health of the lake. The following list includes some of the accomplishments of the Otty Lake Association and residents that have implications for the well-being of the land and water resources of the lake ecosystem. Specific achievements of the Otty Lake community are indicated by an asterisk.

Otty Lake and Catchment Health

Flood Risk

The 1:100 year flood elevation is available for Otty Lake and can be utilized as an additional factor to be considered when assessing site specific development setbacks. 

Septic Inspections

Mandatory septic re-inspection programs for shoreline properties on Otty Lake were introduced by the Townships of Tay Valley in 2012 and Drummond/North Elmsley in 2013. This action was supported by the Otty Lake Association (OLA). A properly functioning septic system is important to reduce bacteria and nutrient inputs to the lake.*

357 mandatory and voluntary septic system re-inspections have been conducted by the Mississippi Rideau Septic System Office on 257 properties around McLaren, Mud and Otty Lake, as a service provided to Drummond/North Elmsley and Tay Valley Townships since 2004.

Shoreline Assessment Report

In 2013, an assessment of the Otty Lake shoreline was carried out under the Love Your Lake Program. Out of the 482 properties assessed, 74 (15 percent) were classified as majority natural, 172 (36 percent) as majority ornamental and 236 (49 percent) as majority regenerative. It is recognised that ornamental or degraded waterfronts will contribute additional nutrients and sediments to a waterbody such as Otty Lake.

Love Your Lake shoreline assessment reports were provided to all property owners regarding the state of their waterfront. These individual reports are confidential and provide recommendations for reducing the impact on lake water quality. An overall assessment of lake shorelines was also made available and an improvement in the naturalization of shorelines was noted in a comparison with a previous survey done in 2005.*

Shoreline Naturalization

In 2009 the OLA introduced a program of offering shoreline plants to Otty Lake residents at subsidized cost with assistance from the RVCA. The choice of plants and the number and size of plants on offer has varied from year-to-year. As of 2017, 1,825 shrubs and trees and 295 native wildflowers have been distributed to lake residents.*

2,506 native trees and shrubs have been planted at 21 project sites along 407 metres of shoreline with services provided by the RVCA Shoreline Naturalization Program.

 

Tree Planting

11,550 trees have been planted at three sites in the Otty Lake catchment by the RVCA Private Land Forestry Program, resulting in the reforestation of seven hectares.

Water Quality

Volunteers from the Otty Lake Association (OLA) conduct an ongoing E.coli sampling program taking 50 or more samples annually at locations around the lake. Results are generally very good, well within the provincial standard for swimming. These OLA volunteers also participate in the MOECC Lake Partner Program sampling for Total Phosphorus and measuring Secchi depths.  Additional sampling for phosphorus and nitrogen is done by OLA volunteers to supplement the RVCA and the Lake Partner Program. The OLA Lake Steward maintains a water quality database that is made available to the RVCA.*

McLaren Lake and Otty Lake are each sampled yearly by the RVCA for five parameters, four times a year along with one stream site on Jebbs Creek being sampled yearly for 22 parameters, six times a year to assess surface chemistry water quality conditions.

One Ontario Benthic Biomonitoring Network site on Jebbs Creek is sampled yearly by the RVCA in the spring and fall of each year with three replicates, to assess instream biological water quality conditions.

21 Rural Clean Water projects were completed by the RVCA Rural Clean Water Program.

Zebra Mussel Monitoring

A program for monitoring Zebra Mussels on collection platforms deployed around Otty Lake was initiated by the OLA in 2014. The abundance of the mussels is cyclic and had declined by 2017.*

Otty Lake and Catchment Habitat

Calendars

The OLA has produced calendars most years featuring the flora or fauna of the Otty Lake watershed. These calendars usually have a stewardship focus and help promote living in harmony with the natural aspects of the lake environment.*

Construction of Wood Duck Nesting and Bat Boxes

In 2015 and 2016 OLA volunteers, with the help of the RVCA, constructed bird and bat boxes. Seventeen wood duck boxes, 15 swallow/bluebird boxes and 26 bat boxes were assembled. These boxes were made available to lake residents and installed at various locations around the lake.*

Fish Habitat

Over a period of four years starting in 2013, a major fish habitat enhancement project was undertaken at Otty Lake. This work was led by the RVCA and the OLA with many community volunteers. Spawning beds for smallmouth bass were constructed during the first three years. Nests for both smallmouth and largemouth bass were constructed in 2016.  Approximately 275 nests were constructed along with the deployment of underwater brush bundles. The occupancy of the nests during the spawning season increased to 55 % by 2016, a remarkable success rate.*

The report "Fish Habitat of the Tay River Watershed: Existing Conditions and Opportunities for Enhancement" was prepared in 2002 by MNR, RVCA, Parks Canada and DFO. A number of specific fish habitat enhancement projects are identified in the report to improve the fishery in Otty Lake and along Jebbs Creek (see pp.117-123).

In-stream Habitat

3.9 kilometres of Jebbs Creek have been surveyed and 32 headwaters sites are sampled once every six years by the RVCA Stream Characterisation Program.

Loon Survey

A loon mapping survey was initiated in April 2016 and is managed by an OLA volunteer. Loon observations noted by lake residents and cottagers are forwarded to the volunteer who incorporates the observations into a map. This map is updated on a regular basis and can be viewed on the OLA website. Annual observations of loons and their offspring on Otty Lake have been reported to Bird Studies Canada/Canadian Lake Loon Survey since 1991.*

Otty Lake Community Feedback

Bear Aware Workshop

In 2017 a black bear awareness workshop was organised by the OLA. A representative of the Ministry of Natural Resources and Forestry was the speaker; over 40 people attended.*

State of the Lake Report

An annual State of the Lake Report was initiated by the OLA in 2014. This comprehensive report provides information regarding water quality, the lake fishery, wildlife habitat, shoreline planting initiatives, the amounts of zebra mussels and algae, among many other topics.*

Website, Newsletter and Summer Information Package

The OLA continues its long standing practice of communicating with lake residents through a newsletter published three times a year and an annual Information Package which is delivered to lake residents by an OLA Area Counsellor. The Otty Lake Association maintains an extensive website for lake residents.*

Otty Lake Association Leadership

Lake Planning

In 2013 a five-year review of the Otty Lake Management Plan was undertaken. Over 200 lake residents and cottagers participated in the associated survey. The results of this review were used to provide guidance to the OLA in developing activities and programs identified by members of the lake community.*

Liaison with Other Lake Associations

The OLA continues to liaise with other local lake associations through its participation in the Lake Networking Group.*

Management of Lake Activities

The OLA has an active 15 member board that meets four times a year. A team of Area Counsellors facilitates interaction between the Board and lake residents and cottagers. A well-attended AGM is held in July.*

7.0 Otty Lake Catchment: Challenges/Issues

Developed by the Otty Lake Association and its partners, the Otty Lake Management Plan (2008) and Five-year Review (2014) provide information on many aspects of the lake environment, as well as issues of concern identified by the lake community that could threaten the long-term health of the lake. The following list includes some of those identified issues that have implications for the water and land resources of the lake ecosystem. Specific issues noted by the lake community are indicated by an asterisk.

Development

Waterfront property development is occurring primarily through the transformation of traditional, seasonal cottages into larger year-round dwellings. This transition is taking place either through re-development of an existing cottage lot or incremental alterations (additions, sleeping cabins, gazebos, decks, sheds, boat houses, garages, lawns, shoreline modifications, docks), all of which may put additional stress on the sensitive shoreline zone and the lake along with potential, added septic system loading.

Many waterfront properties contain existing non-conforming dwellings with respect to minimum water frontage and lot area and are often located within 30 metres of the water that require minor variances for expansion and/or reconstruction of dwellings where standard development setbacks from water are difficult to achieve. In these cases, of which there are many, staff at Drummond/North Elmsley and Tay Valley Townships and the Conservation Authority often meet with resistance and push back when attempts are made to implement standards for development setbacks, vegetated shorelines and septic systems.

Monitoring implementation of conditions of planning and regulatory approvals is challenging due to a lack of resources.

Headwaters/In-Water Habitat/Shorelines

Otty Lake has 62 percent of its shoreline composed of natural vegetation. This is below the 75 percent target that is recommended by experts for the protection of the catchment’s waterbodies and watercourses, 30 metres back from the shoreline of streams, rivers and lakes (see Section 4.4 of this report).

Otty Lake has seen a small increase in the area of settlement (0.28 ha.) along its shoreline between 2008 and 2014, due primarily to a loss of woodland.

Six of thirty-two sampled headwater sites in the catchment have been modified (three are channelized, three are roadside ditches)(see Section 3.4.2 of this report).

Littoral zone mapping identifying substrate type, vegetation and habitat features along with opportunities for shoreline enhancement is unavailable for Otty Lake.

 

Land Cover

Land cover has changed across the catchment (2008 to 2014) largely as a result of an increase in the area of settlement (11 ha.) and loss of woodland (7 ha.) and crop and pastureland (3 ha.)(see Section 4.1 of this report).

Wetlands have declined by thirty-one percent since European pre-settlement and now cover 21 percent (1112 ha.) of the catchment (in 2014). Eighty-six percent (953 ha.) of these wetlands remain unevaluated and unregulated and although they are not under imminent threat from development activity, they do remain vulnerable to drainage and land clearing activities in the absence of any regulatory and planning controls that would otherwise protect them for the many important hydrological, social, biological and ecological functions/services/values they provide to landowners and the surrounding community (see Section 4.3 of this report).

Water Quality

Jebbs Creek surface chemistry water quality does not exhibit any sampling concerns (see Section 2.3 of this report).

McLaren Lake surface chemistry water quality rating ranges from Poor to Fair (see Section 2.2 of this report).

Otty Lake surface chemistry water quality rating ranges from Fair to Good (see Section 2.1 of this report).

Jebbs Creek instream biological water quality conditions range from Poor to Fair (see Section 3.3.1 of this report).

Twenty-five (of 348) Tay Valley Township mandatory septic system inspections conducted from 2004 to 2017 on Otty Lake revealed the need for remedial work on 18 systems and replacements for seven systems. More information was supplied to two other landowners with septic system issues. Those properties with concerns are identified in the yearly report submitted by the Mississippi Rideau Septic System Office to the Township.

One (of nine) Tay Valley Township voluntary septic system inspections conducted from 2004 to 2017 on McLaren and Mud Lake revealed the need for remedial work to be performed. Those properties with concerns are identified in the yearly report submitted by the Mississippi Rideau Septic System Office to the Township.

8.0 Otty Lake Catchment: Actions/Opportunities

Developed by the Otty Lake Association and its partners, the Otty Lake Management Plan (2008) and Five-year Review (2014) provide information on many aspects of the lake environment, as well as actions to maintain and improve the long-term health of the lake. The following list includes some of those identified actions that have implications for the land and water resources of the lake ecosystem. Specific opportunities noted by the Otty Lake community are indicated by an asterisk. 

Otty Lake and Catchment Health

Development

Work with approval authorities (Drummond/North Elmsley Township, Lanark County, Leeds Grenville and Lanark District Health Unit, Mississippi Rideau Septic System Office, RVCA and Tay Valley Township) and waterfront property owners (including the McLaren Lake community and Otty Lake Association) to consistently implement current land use planning and development policies for water quality and shoreline protection adjacent to Jebbs Creek, McLaren Lake, Otty Lake and headwater streams in the catchment (i.e., a minimum 30 metre development setback from water).

Explore ways and means to more effectively enforce and implement conditions of land-use planning and development approval to achieve net environmental gains (particularly with respect to rehabilitating or protecting naturally vegetated shorelines and water quality).

Encourage Committees of Adjustment to take advantage of technical and environmental information and recommendations forthcoming from planning and environmental professionals.

Municipalities in the Tay Watershed are encouraged to strengthen natural heritage and water resources official plan policies and zoning provisions (pertaining to water setbacks, frontage and naturalized shorelines and wetland protection) where deemed appropriate. 

Work with Drummond/North Elmsley Township, Lanark County, Tay Valley Township and agencies to ensure that development approvals around lakes and along watercourses take into consideration the protection of fish habitat (including the near-shore nursery and spawning habitat).

Municipal and agency planners together with development proponents are to use the 2014 Site Evaluation Guidelines to inform decision-making about the application of development setbacks on lots with shallow soils/bedrock, steep slopes and sparse vegetation cover along with the use of the appropriate, development related, best management practices.

Utilise RVCA subwatershed and catchment reports to help develop/revise official plan policies to protect surface water resources and the natural environment (including woodlands, wetlands and shoreline cover).

Use 1:100 year flood elevation information now available for Otty Lake as an additional factor to be considered when assessing development setbacks at the shoreline and protecting property owners from flood hazards.

Establish RVCA regulation limits around the 86 percent (953 ha.) of wetlands in the catchment that are unevaluated. Doing this will help protect landowners from natural hazards including  mitigating surface water flow by storing water during periods of peak flow (such as spring snowmelt and heavy rainfall events) and releasing water during periods of low flow (this mitigation of water flow reduces flood damage), as well as contributing to the stabilisation of shorelines and to the reduction of soil erosion damage through water flow mitigation and plant soil binding/retention.

Shorelines

Implement Otty Lake shoreline improvement recommendations from the 2013 Love Your Lake Program waterfront assessments.*

Take advantage of the RVCA Shoreline Naturalization Program to re-naturalize altered creek, lake and stream shoreline identified in this report as “Unnatural Riparian Land Cover". Concentrate stewardship efforts on Otty Lake waterfront properties shown in orange on the Riparian Land Cover map (see Figure 69 in Section 4.4 in this report). Other stewardship opportunities in the catchment may be determined based on septic system inspections and surface water quality monitoring results.

Promote the use of bioengineering methods (using native shrub/tree planting, fascines, live stakes) as a shoreline erosion mitigation measure as well as a cost effective alternative to shoreline hardening (with rip rap, armour stone, gabion baskets, walls)

Educate landowners about the value and importance of natural shorelines and property best management practices with respect to shoreline use and development, septic system installation and maintenance and shoreline vegetation retention and enhancement (Drummond/North Elmsley Township, Leeds Grenville and Lanark District Health Unit, McLaren Lake community, Mississippi Rideau Septic System Office, Otty Lake Landowners’ Association, RVCA and Tay Valley Township).

Water Quality

Consider further investigation of the 1) Fair to Good surface chemistry water quality rating on Otty Lake; 2) Poor to Fair surface chemistry water quality rating on McLaren Lake and 3) Poor to Fair instream biological water quality rating in Jebbs Creek, as part of a review of RVCA's Watershed Watch, Baseline and Benthic Invertebrate surface water quality monitoring.

Offer funding provided by the RVCA Rural Clean Water Program to landowners with potential projects that could improve water quality on McLaren, Mud and Otty Lakes and their tributaries (e.g., livestock fencing, septic system repair/replacement and streambank erosion control/stabilisation). Concentrate efforts at septic systems requiring remedial work or replacement, including the 26 identified as needing additional maintenance/remedial/replacement work since 2004.

Educate waterfront property owners about septic system care by providing information about sewage system maintenance (i.e., when to pump out septic systems and holding talks) through initiatives such as the Septic Savvy Workshop and services provided by the Mississippi Rideau Septic System Office.

Reduce pollutant loading to Otty Lake through education about the application of shoreline, stormwater and agricultural best management practices; also consider using low impact development (LID) methods to improve the quality and reduce the amount of stormwater runoff directly reaching the lake ecosystem. This will be particularly beneficial in areas with extensive impervious surfaces (i.e., asphalt, concrete, buildings, and severely compacted soils) or on sensitive waterfront properties (with steep slopes/banks, shallow/impermeable soils).

 

Otty Lake and Catchment Habitat

Aquatic Habitat/Fisheries/Wildlife

Educate waterfront property owners about: 1) fish habitat requirements, spawning timing and near-shore and in-water activities that can disturb or destroy fish habitat and spawning sites 2) the causes of excessive algae and aquatic vegetation growth (see the RVCA publication entitled Algae and Aquatic Plant Educational Manual) and 3) healthy lake ecosystems and associated water level fluctuations in a natural environment.

Work with the Otty Lake Association on fish and wildlife habitat improvement.

Otty Lake Association Leadership

Lake Planning

Conduct a ten-year review of the Otty Lake Management Plan (2008), scheduled for completion in the summer of 2018. This review will also use a survey of lake residents and cottagers to provide feedback on topics of interest and importance and help establish opportunities for future action on Otty Lake.*

Continue the annual Otty Lake State of the Lake Report. This comprehensive report on lake health and OLA initiatives in the Lake Watershed will continue to serve as an important source of information for the lake community.* 

The Otty Lake Association will lead the coordination of the implementation of the recommendations of the updated Otty Lake Management Plan (2018).*

Use the information contained in the Tay River Subwatershed Report 2017 and Otty Lake Catchment Report 2017 to assist with implementation of the updated Otty Lake Management Plan (2018).

Full Catchment Report