Jock River Subwatershed Report 2016
Jock River-Barrhaven Catchment
The RVCA produces individual reports for 12 catchments in the Jock River subwatershed. Using data collected and analyzed by the RVCA through its watershed monitoring and land cover classification programs, surface water quality and in-stream conditions are reported for the Jock River along with a summary of environmental conditions for the surrounding countryside every six years.
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).
The following sections of this report for the Jock River-Barrhaven catchment are a compilation of that work.
|Surface Water Quality Conditions
|Land Stewardship and Water Resources Protection
For other Jock River catchments and the Jock River Subwatershed Report, please visit the RVCA website at www.rvca.ca
Figure 1 Land cover in the Barrhaven catchment
1.0 Jock River-Barrhaven Catchment: Facts
1.1 General/Physical Geography
- Ottawa: (31 km2; 100% of catchment)
- The Barrhaven Catchment resides within an extensive physiographic region known as the Ottawa Valley Clay Plain. The sediment was deposited in the Champlain Sea after the last glaciation. This part of the clay plain is approximately 8 to 10 metres deep. It is truncated to the north by Paleozoic bedrock and to the west by a regional geological sand and gravel feature known as the Kars Esker; while glacial till flanks the eastern extent of the catchment
- In this catchment, the clay plain is underlain by dolostone, interbedded sandstone/dolostone and limestone from the Oxford, March and Bobcaygeon Formations, respectively. In addition, several geologic faults may pass through the catchment
- The ground surface ranges in elevation from 120 masl along Moodie Drive north of Fallowfield Road to 80 masl at the confluence of the Jock River with the Rideau River
- Surficial karst may be present near Hwy 416 in this catchment
- 31 square kilometers; occupies five percent of the Jock River subwatershed, one percent of the Rideau Valley watershed
- Jock River and tributaries: 50 km
1.2 Vulnerable Areas
- Jock River is subject to a flooding hazard during the regional storm flood (the 100 year flood). Surveys and studies undertaken in accordance with provincial standards have determined that the 100 year flood elevation in the catchment ranges from 92.7 metres above mean sea level at the upper, mapped extent of the regulation limit at Moodie Drive to 80.3 metres above mean sea level at its confluence with the Rideau River downstream of Prince of Wales Drive
- The Mississippi-Rideau Source Protection initiative has mapped the southern part of this catchment as a Significant Groundwater Recharge Area and parts of the catchment as Highly Vulnerable Aquifer. There are no Well Head Protection Areas in the catchment
- 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 Barrhaven catchment
1.3 Conditions at a Glance
- Surface chemistry water quality rating in the Barrhaven catchment is “Fair” at both sites over the two reporting periods (2004-2009 and 2010-2015). Frequent high nutrient concentrations and occasional exceedances of copper and aluminium contributed to the rating
- Instream biological water quality conditions at the Jock River Barrhaven sample location range from “ Poor” to “Good” from 2004 to 2015 (using a grading scheme developed by Ontario Conservation Authorities in Ontario for benthic invertebrates) with an overall benthic invertebrate water quality rating of “Good” determined for this period
Instream and Riparian
- Overall instream and riparian condition for the Jock River-Barrhaven catchment as assessed by the stream characterization and headwater drainage feature assessment programs show that the Jock River and its tributaries are in generally good condition. The majority of the system has low erosion levels and a moderately healthy riparian corridor. Instream diversity of aquatic habitat is variable along much of the system
- Warm/cool water thermal guild supporting the Jock River/Rideau River fishery
- Thirty-six species of recreational and bait fish
Shoreline Cover Type (30 m. riparian area; 2014)
- Crop and Pasture (36%)
- Settlement (29%)
- Woodland (20%)
- Transportation (11%)
- Aggregate (3%)
- Wetland (1%)
Land Cover Type (2014)
- Settlement (42%)
- Crop and Pasture (20%)
- Transportation (14%)
- Woodland (11%)
- Aggregate (9%)
- Water (2%)
- Meadow-Thicket (1%)
- Wetland (<1%)
Land Cover Change (2008 to 2014)
- Crop and Pasture (-250 ha)
- Woodland (-27 ha)
- Meadow-Thicket (0 ha)
- Aggregate (+2 ha)
- Wetland (+2 ha)
- Water (+4 ha)
- Transportation (+108 ha)
- Settlement (+160 ha)
Significant Natural Features
- Stony Swamp Provincially Significant Wetland
- Several hundred (~350) operational private water wells in the Barrhaven catchment. Groundwater uses are mainly domestic but also include livestock watering, groundwater monitoring and testing and municipal, commercial and other public water supplies
- There are parts of 3 bedrock quarry licenses and 9 sand and gravel pit licenses located within the catchment. Sand and gravel resources are mainly of secondary importance
Species at Risk (Elemental Occurrence)
- Snapping Turtle (Special Concern)
1.4 Catchment Care
- Twenty-one stewardship projects undertaken (see Section 5)
- Chemical surface (in-stream) water quality collection since 2003 (see Section 2)
- Benthic invertebrate (aquatic insect) surface (in-stream) water quality collection since 2003 (see Section 3.3.1)
- Fish survey along the Jock River (see Section 3.3.11)
- Stream characterization survey on the Jock River in 2015, working upstream to the headwaters from its mouth where it empties into the Rideau River, taking measurements and recording observations on instream habitat, bank stability, other attributes and preparing a temperature profile (see Section 3)
- Five headwater drainage feature assessments in 2015 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)
- Groundwater level and chemistry data is available from a PGMN well located in the Hearts Desire community (W085). Additional groundwater chemistry information is available from the Ontario Geological Survey for two wells located in this catchment
- Development along the Jock River and in and adjacent to the Stony Swamp Provincially Significant Wetlands 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
- Approximately 30 Environmental Compliance Approvals and/or Environmental Activity and Sector Registrations in this catchment. Most of these approvals/registrations are for municipal and private sewage works, while others are for private water works, waste management systems, a standby power system industrial sewage disposal systems and air emissions. An active municipal landfill is in the southern part of this catchment
- Approximately 28 active Permits To Take Water (PTTW), most of which have been issued for construction dewatering or similar activities; several for golf course irrigation; a couple for quarry dewatering; and one for municipal landfill activities
2.0 Jock River-Barrhaven Catchment: Surface Water Quality Conditions
Surface water quality conditions in the Jock River-Barrhaven catchment are monitored by the City of Ottawa’s Baseline Water Quality Monitoring Program. This program provides information on the condition of Ottawa’s surface water resources; data is collected for multiple parameters including nutrients (total phosphorus, total Kjeldahl nitrogen and ammonia), E. coli, metals (like aluminum and copper) and additional chemical/physical parameters (such as alkalinity, chlorides, pH and total suspended solids). The locations of monitoring sites are shown in Figure 2 and Table 1.
Figure 2 Water quality monitoring sites on the Jock River in the Barrhaven Catchment
2.1 Jock River Water Quality Rating
There are two monitored water quality sites on the Jock River in the Barrhaven Catchment (JR-01 and JR-02), the RVCA's water quality rating for these are “Fair” (Table 1) as determined by the Canadian Council of Ministers of the Environment (CCME) Water Quality Index. A “Fair” rating indicates that water quality is usually protected but is occasionally threatened or impaired; conditions sometimes 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. Analysis of the data has been broken into two periods; 2004 to 2009 and 2010 to 2015 to examine if conditions have changed between these periods. Table 1 shows the overall rating for the monitored surface water quality sites within the Jock River-Barrhaven catchment and Table 2 outlines the Water Quality Index (WQI) scores and their corresponding ratings.
Both sites had only small changes between the two reporting periods, with minor improvements in the water quality score. The scores at these sites are largely influenced by frequent high nutrient concentrations and occasional metal exceedances. For more information on the CCME WQI, please see the Jock River Subwatershed Report. For more information on the CCME WQI, please see the Jock River Subwatershed Report.
Water Quality Index ratings for the Jock River-Barrhaven Catchment
Water Quality Index ratings and corresponding index scores (RVCA terminology, original WQI category names in brackets)
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) and ammonia (NH3) are used as secondary indicators of nutrient loading. RVCA uses a guideline of 0.500 mg/l to assess TKN and the PWQO of 0.020 mg/l to assess NH3 concentrations in the Jock River.
Tables 3, 4 and 5 summarize average nutrient concentrations at monitored sites within the Jock River-Barrhaven catchment and show the proportion of results that meet the guidelines.
Table 3 Summary of total phosphorus results for the Jock River-Barrhaven catchment, 2004-2009 and 2010-2015. Highlighted values indicate average concentrations exceed the guideline
Table 4 Summary of total Kjeldahl nitrogen results for the Jock River-Barrhaven catchment from 2004-2009 and 2010-2015. Highlighted values indicate average concentrations exceed the guideline
Table 5 Summary of ammonia results for Jock River-Barrhaven catchment from 2004-2009 and 2010-2015. Highlighted values indicate average concentrations exceed the guideline
Monitoring Site JR-01
The majority of samples at site JR-01 were above the TP guideline from 2004-2009; however the proportion of exceedances decreased in the 2010-2015 monitoring period (Figures 3 and 4). The number of samples below the guideline improved from 38 percent in 2004-2009 to 48 percent in 2010-2015, and the average TP concentrations decreased slightly from 0.037 mg/l (2004–2009) to 0.033 mg/l (2010–2015) as shown in Table 3.
TKN concentrations show that the bulk of results exceeded the guideline (Figures 5 and 6); there were few samples (eight percent) below the guideline in the 2004-2009 period and this declined to only two percent in the 2010-2015 period. The average concentration was generally elevated and increased from 0.698 mg/l to 0.714 mg/l (Table 4).
In the 2004-2009 reporting period 56% of NH3 results were below the guideline with an average concentration of 0.034 mg/l (Figure 7, Table 5). The percentage of results below the guideline declined to 41% in the 2010-2015 period, though the average concentration decreased to 0.028 mg/l (Figure 8, Table 5). The overall reduction in NH3 concentrations may be influenced by the lack of samples in March during the 2010-2015 period (Figure 8). In the 2004-2009 period samples in March had the greatest concentrations (Figure 7), likely influenced by the impact of meltwater conditions which increases runoff and potential loadings to the river.
Monitoring Site JR-02
Elevated TP results were a common occurrence at site JR-02 and remained consistent between the two monitoring periods; 41 percent of samples were below the guideline in the 2004-2009 period (Figure 3); this remained consistent at 42 percent of samples in the 2010-2015 period (Figure 4). The average TP concentration was largely unchanged decreasing only slightly from 0.038 mg/l (2004-2009) to 0.036 mg/l (2010-2015) as shown in Table 3.
The bulk of TKN results have exceeded the guideline (Figure 5 and 6), with six percent of samples below the guideline in the 2004-2009 period, decreasing to no samples below the guideline in 2010-2015. The average concentration was elevated and increased from 0.706 mg/l to 0.714 mg/l (Table 4).
The results for NH3 indicate that exceedances were common. Fifty-four percent of results were below the guideline in 2004-2009 (Figure 7); this decreased to 35 percent in the 2010-2015 reporting period (Figure 8). The average NH3 concentration decreased marginally from 0.037 mg/l to 0.034 mg/l (Table 5).
Figure 3 Total phosphorous concentrations in the Jock River, 2004-2009
Figure 4 Total phosphorous concentrations in the Jock River, 2010-2015
Figure 5 Total Kjeldahl nitrogen concentrations in the Jock River, 2004-2009
Figure 6 Total Kjeldahl nitrogen concentrations in the Jock River, 2010-2015
Figure 7 Ammonia concentrations in the Jock River, 2004-2009
Figure 8 Ammonia concentrations in the Jock River, 2010-2015
Nutrient enrichment has previously been identified as a feature in this reach of the Jock River. Overall, average nutrient concentrations have remained consistent through the monitoring periods, with few changes in some sites or parameters. All parameters (total phosphorus, total Kjeldahl nitrogen and ammonia) exceed their respective guidelines reguarly. Elevated nutrients may result in nutrient loading downstream and to the Rideau River. High nutrient concentrations can help stimulate the growth of algae blooms and other aquatic vegetation in a waterbody and deplete oxygen levels as the vegetation dies off. Best management practices such as minimizing storm water runoff, enhanced shoreline buffers, minimizing/discontinuing the use of fertilizers and restricting livestock access in upstream agricultural areas can help to reduce nutrient enrichment in Jock River and subsequent impacts on the Rideau River.
2.3 Escherichia coli
Escherichia 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 millilitres (CFU/100 ml) is used. E. coli counts greater than this guideline indicate that bacterial contamination may be a problem within a waterbody.
Table 6 summarizes the geometric mean for the monitored sites on the Jock River within the Barrhaven catchment and shows the proportion of samples that meet the E. coli guideline of 100 CFU/100 ml. The results of the geometric mean with respect to the guideline for the two periods, 2004-2009 and 2010-2015, are shown in Figures 9 and 10 respectively.
Summary of E. coli
results for the Jock River, 2004-2009 and 2010-2015
Monitoring Site JR-01
E. coli counts at site JR-01 indicate little change with regard to bacterial contamination. The proportion of samples below the guideline rose marginally from 78 percent (Figure 9) to 80 percent (Figure 10). The count at the geometric mean increased from 39 CFU/100ml in 2004-2009 to 46 CFU/100ml from 2010-2015 (Table 6). Although the count at the geometric mean increased, the geometric mean is below the guideline and the majority of samples are below the PWQO for E. coli.
Monitoring Site JR-02
Elevated E. coli counts at site JR-02 occurred occasionally. The proportion of samples below the guideline decreased from 83 percent (Figure 9) from 2004-2009 to 73 percent (Figure 10) from 2010-2015. The count at the geometric mean also increased slightly between the two monitoring periods from 43 CFU/100ml to 47 CFU/100ml (Table 6). Although E. coli counts did increase marginally the geometric mean is well below the E. coli PWQO.
Figure 9 Geometric mean of E. coli results in the Jock River, 2004-2009
Figure 10 Geometric mean of E. coli results in the Jock River, 2010-2015
Bacterial contamination does not appear to be a significant concern in this reach of the Jock River. Both sites (JR-01 and JR-02) have occasional exceedances and counts at the geometric mean below the guideline of 100 CFU/100ml. Best management practices such as enhancing shoreline buffers, limiting livestock access and minimizing runoff in both rural and urban areas can help to protect this reach of the Jock River into the future.
Of the metals routinely monitored in the Jock River (Barrhaven Catchment) aluminum (Al) and copper (Cu) occasionally reported concentrations above their respective PWQOs. For Al, the PWQO is 0.075 mg/l and for Cu it is 0.005 mg/l. In elevated concentrations, these metals can have toxic effects on sensitive aquatic species.
Tables 7 and 8 summarize metal concentrations at sites JR-01 and JR-02 as well as show the proportion of samples that meet guidelines. Figures 11 to 14 show metal concentrations with respect to the guidelines for the two periods of interest, 2004–2009 and 2010–2015.
Table 7 Summary of aluminum results in the Jock River from 2004-2009 and 2010-2015. Highlighted values indicate average concentrations exceed the guideline
Table 8 Summary of copper results for the Jock River from 2004-2009 and 2010-2015
Monitoring Site JR-01
The average Al concentrations in site JR-01 exceeded the guideline. Most samples (66 percent) were below the guideline (Figure 11) from 2004-2009, this declined marginally to 64 percent (Figure 12) of results reporting below the guideline from 2010-2015. The average concentration increased from 0.085 mg/l to 0.094 mg/l (Table 7).
Copper concentrations occasionally exceeded the PWQO, with 75 percent of samples below the guideline in 2004-2009 (Figure 12). The Cu concentrations increased to 84 percent of samples being below the guideline in 2010-2015 (Figure 14). The average concentration of copper marginally decreased during the two reporting periods from 0.0036 mg/l to 0.0026 mg/l (Table 8). The lack of sampling in March for the 2010-2015 period (Figure 14) may account for this apparent decrease, as elevated results were observed in March during the 2004-2009 period (Figure 13).
Monitoring Site JR-02
Results from JR-02 provide evidence of increasing Al concentrations between the two reporting periods. Seventy-one percent of samples were below the guideline in the 2004-2009 period (Figure 11). This decreased to 59 percent of samples in the 2010-2015 period (Figure 12). The average concentration of Al was 0.075 mg/l from 2004-2009 and increased to 0.099 mg/l from 2010-2015 (Table 7).
Copper concentrations have occasionally exceeded the guidelines but did not show marked change between the two reporting periods. In the 2004-2009 period 76 percent of samples were below the guideline (Figure 13) and rose slightly to 78 percent of samples in the 2010-2015 period (Figure 14). The average concentrations (Table 8) increased marginally from 0.0034 mg/l (2004-2009) to 0.0037 mg/l (2010-2015).
Figure 11 Average aluminum concentrations in the Jock River, 2004-2009
Figure 12 Average aluminum concentrations in the Jock River, 2010-2015
Figure 13 Average copper concentrations in the Jock River, 2004-2009
Figure 14 Average copper concentrations in the Jock River, 2010-2015
In the Barrhaven catchment aluminum concentrations have increased at both sites JR-01 and JR-02 while copper concentrations have remained consistent. Most increases in concentrations are observed during the spring likely due to increased runoff amounts from melt conditions; runoff picks up pollutants from farms, yards, roads and parking lots. As there has been increased urbanization in this area it is likely that runoff from hardened surfaces (roadways, parking lots, etc.) is influencing metal concentrations. Continued efforts should be made to identify pollution sources and implement best management practices to reduce any inputs such as storm water runoff to improve overall stream health and lessen downstream impacts.
1 The City of Ottawa Baseline Water Quality Monitoring Program has also applied the CCME WQI to monitored sites. The parameters used and time periods differs between the RVCA and City of Ottawa’s application of the WQI, thus has resulted in different ratings at some sites.
2 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
3 Rideau Valley Conservation Authroity. (2010). Jock River Subwatershed Report.
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 summarize a variable that varies over several orders of magnitude, such as E. coli counts.
5 City of Ottawa Water Environment Protection Program. (2006). Water Quality in Ottawa's Rivers and Streams.
3.0 Jock River-Barrhaven Catchment: Riparian Conditions
3.1 Jock River Overbank Zone
3.1.1 Riparian Buffer Land Cover Evaluation
Figure 15 demonstrates the buffer conditions of the left and right banks separately. The Jock River in the Barrhaven catchment had a buffer of greater than 30 meters along 52 percent of the right bank and 57 percent of the left bank. A five meter or less buffer was present along 29 percent of the right bank and 18 percent of the left bank.
Figure 15 Riparian Buffer Evaluation along the Jock River in the Barrhaven catchment
3.1.2 Riparian Buffer Alterations
Alterations within the riparian buffer area 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 16). The riparian buffer zone along the Jock River within the Barrhaven catchment was found to have highly variable conditions along the riparian corridor. These alterations were generally associated with road crossings, shoreline hardening and residential/infrastructure/agricultural land uses.
Figure 16 Riparian buffer alterations within the Jock River Barrhaven catchment
3.1.3 Adjacent Land Use
The RVCA’s Stream Characterization Program identifies seven different land uses beside the Jock River in the Barrhaven catchment (Figure 17). 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 65 percent of the stream, characterized by forest, scrubland and meadow. Forest habitat was dominant in the adjacent lands along the Jock River in the Barrhaven catchment at 42 percent. The remaining land use consisted of active agriculture, residential, recreational and infrastructure in the form of road crossings.
Figure 17 Land Use along the Jock River in the Barrhaven catchment
3.2 Jock River 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. High levels of erosion were observed along the left bank immediately upstream of the Hearts Desire weir as well as at various locations downstream of the 416 crossing. Figure 18 shows low to high levels of erosion along the Jock River in the Barrhaven catchment.
Figure 18 Erosion along the Jock River in the Barrhaven catchment
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 19 shows that the Jock River in the Barrhaven catchment had low to high levels of undercut banks along the system. High levels of undercut banks were present in the upper reaches of the Barrhaven catchment at various locations upstream and downstream of the 416 highway crossing.
Figure 19 Undercut stream banks along the Jock River in the Barrhaven catchment
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 1m above the water surface. Figure 20 shows low to moderate levels of stream shading dominate conditions in most reaches of the Jock River in the Barrhaven catchment.
Figure 20 Stream shading along the Jock River in the Barrhaven catchment
3.2.4 Instream Woody Debris
Figure 21 shows that the majority of the Jock River in the Barrhaven catchment had low to moderate levels of instream woody debris in the form of branches and trees. Instream woody debris is important for fish and benthic invertebrate habitat, by providing refuge and feeding areas.
Figure 21 Instream woody debris along the Jock River in the Barrhaven catchment
3.2.5 Overhanging Trees and Branches
Trees and branches that are less than one meter from the surface of the water are defined as overhanging. Overhanging branches and trees provide a food source, nutrients and shade which helps to moderate instream water temperatures. Figure 22 shows the system is highly variable with low to high levels of overhanging branches and trees along the Jock River in the Barrhaven catchment.
Figure 22 Overhanging trees and branches along the Jock River in the Barrhaven catchment
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 23 shows 31 percent of the Jock River in the Barrhaven catchment remains “unaltered” with no anthropogenic alterations. Fifty three percent of the Jock River in the Barrhaven catchment was classified as natural with minor anthropogenic changes, 14 percent was classified as altered and one percent was considered highly altered. The alterations along the Jock River in this reach were in the form of reduced buffers, shoreline modifications and road crossings.
Figure 23 Anthropogenic alterations along the Jock River in the Barrhaven catchment
3.3 Jock River 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 Prince of Wales site on the Jock River since 2004. Monitoring data is analyzed for each sample site and the results are presented using the Family Biotic Index, Family Richness and percent Ephemeroptera, Plecoptera and Trichoptera.
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 Jock River Barrhaven catchment sample location at Prince of Wales are separated by reporting period 2004 to 2009 and 2010 to 2015. “Good” to “Poor” water quality conditions being observed at the Jock River Barrhaven sample location for the period from 2004 to 2015 (Fig.24) using a grading scheme developed by Conservation Authorities in Ontario for benthic invertebrates.
Figure 24 Hilsenhoff Family Biotic Index at the Jock River Prince of Wales sample location
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 Jock River Barrhaven site is reported to have “Fair” to “Good” family richness (Fig.25).
Figure 25 Family Richness at the Jock River Prince of Wales sample location
Ephemeroptera (Mayflies), Plecoptera (Stoneflies), and Trichoptera (Caddisflies) are species considered to be very sensitive to poor water quality conditions. High abundance of these organisms is generally an indication of good water quality conditions at a sample location. As a result, the EPT indicates that the Jock River Barrhaven sample location is reported to have “Fair” to “Good” water quality (Fig.26) from 2004 to 2015.
Figure 26 EPT at the Jock River Prince of Wales sample location
Overall the Jock River Barrhaven sample location aquatic habitat conditions from a benthic invertebrate perspective is considered “Good” from 2004 to 2015 as the samples are dominated by species that are moderately sensitive and sensitive 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.
Diverse habitat cover was identified throughout the Jock River Barrhaven reach, with considerable coverage across the surveyed stream (Figure 27). Many of these sections represent potentially crucial habitat for resident species. Regions with reduced habitat complexity were observed in the middle reaches within the catchment.
Figure 27 Habitat complexity along the Jock River in the Barrhaven catchment
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 28 shows that 78 percent of the sections observed on the Jock River Barrhaven had the presence of clay substrate and 71% of the sections contained silt. Cobble was present within 70% of the sections, while boulders were present in 55% of surveyed sections. Overall substrate conditions were diverse along the Jock River Barrhaven reach. Figure 29 shows the dominant substrate type observed for each section surveyed along the Jock River in the Barrhaven catchment.
Figure 28 Instream substrate along the Jock River in the Barrhaven catchment
Figure 29 Dominant substrate type along the Jock River in the Barrhaven catchment
3.3.4 Instream Morphology
Pools and riffles are important habitat features for aquatic life. Riffles are fast flowing areas characterized 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 characterized by minimal flows, with relatively deep water and winter and 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 center of the channel. Figure 30 shows that the Jock River Barrhaven catchment is fairly diverse; 61 percent consists of runs, 18 percent riffles and 21 percent pools. Figure 31 shows where the riffle habitat areas were observed along the Jock River in the Barrhaven catchment.
Figure 30 Instream morphology along the Jock River in the Barrhaven catchment
Figure 31 Riffle habitat locations along the Jock River in the Barrhaven catchment
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
- Stabilizing 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. Narrow leaved emergents were present at 96% of the sections surveyed, algae was observed in 86% of sections, while free floating plants were observed in 67% of surveyed sections. Broad leaved emergents were observed in 58% of sections, submerged plants in 57%, floating plants in 53% and robust emergents in only 33% of sections surveyed. Figure 32 depicts the plant community structure for the Jock River Barrhaven catchment. Figure 33 shows the dominant vegetation type observed for each section surveyed along the Jock River in the Barrhaven catchment.
Figure 32 Vegetation type along the Jock River in the Barrhaven catchment
Figure 33 Dominant vegetation type along the Jock River in the Barrhaven catchment
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 34 demonstrates that the Jock River Barrhaven reach had no vegetation to low levels of instream vegetation for 76 percent of its length. Clay and bedrock substrate conditions can limit the amount of instream vegetation which is the likely factor for low vegetation levels along this reach of the Jock River. Normal to common levels of vegetation were recorded at only 22 percent of stream surveys.
Figure 34 Instream vegetation abundance along the Jock River in the Barrhaven catchment
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. Sixty nine percent of the sections surveyed along the Jock River Barrhaven reach had invasive species (Figure 35). The invasive species observed in the Jock River Barrhaven reach were European frogbit, purple loosestrife, poison/wild parsnip, carp, banded mystery snail, dog strangling vine, yellow iris, bull thistle, Eurasian milfoil and Manitoba maple. 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 36).
Figure 35 Invasive species abundance along the Jock River in the Barrhaven catchment
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.
188.8.131.52 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 37 shows that the dissolved oxygen in the Jock River Barrhaven catchment was within the threshold for warmwater biota in this reach of the system. The average dissolved oxygen levels observed within the main stem of the Jock River Barrhaven catchment was 8.67 mg/L.
Figure 37 Dissolved oxygen ranges in the Jock River Barrhaven catchment
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 Jock River in the Barrhaven catchment was 662 µs/cm. Figure 38 shows the conductivity readings for the Jock River Barrhaven catchment.
Figure 38 Specific conductivity ranges in the Jock River Barrhaven catchment
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 the Jock River Barrhaven catchment averaged 7.94 thereby meeting the provincial standard (Figure 39).
Figure 39 pH ranges in the Jock River Barrhaven catchment
184.108.40.206 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 stabilize 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 summarized into 6 classes:
- <100% Saturation / <6.0 mg/L Concentration. Oxygen concentration and saturation are not sufficient to support aquatic life and may represent impairment
- >100% Saturation / <6.0 mg/L Concentration. Oxygen concentration is not sufficient to support aquatic life, however saturation levels indicate that the water has stabilized at its estimated maximum. This is indicative of higher water temperatures and stagnant flows.
- <100% Saturation / 6.0-9.5 mg/L Concentration. Oxygen concentration is sufficient to support warm water biota, however depletion factors are likely present and are limiting maximum saturation.
- >100% Saturation / 6.0-9.5 mg/L Concentration. Oxygen concentration and saturation levels are optimal for warm water biota.
- <100% Saturation / >9.5 mg/L Concentration. Oxygen concentration is sufficient to support cold water biota, however depletion factors are likely present and are limiting maximum saturation.
- >100% Saturation / >9.5 mg/L Concentration. Oxygen concentration and saturation levels are optimal for coldwater biota.
Figure 40 A bivariate assessment of dissolved oxygen concentration (mg/L) and saturation (%) on the Jock River Barrhaven reach
Dissolved oxygen conditions on the Jock River in the Barrhaven catchment are generally sufficient for both warm and coldwater species (Figure 40).
220.127.116.11 Specific Conductivity Assessment
Specific conductivity (SPC) is a standardized 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 summarize 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 of the Jock River Barrhaven catchment, with moderately elevated levels observed in the lower reaches (Figure 41). Highly elevated conditions were identified in the lower reach of the system, and generally correspond with proximity to the Hearts Desire weir and storm water inputs.
Figure 41 Relative specific conductivity levels on the Jock River in the Barrhaven catchment
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 42 shows where the thermal sampling sites were located along the Jock River Barrhaven catchment. Analysis of the data collected indicates that the Jock River Barrhaven catchment is classified as a warm water system with cool to warm water reaches (Figure 43).
Figure 42 Temperature logger locations on the Jock River in the Barrhaven catchment
Figure 43 Temperature logger data for three sites on the Jock River in the Barrhaven catchment
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
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 44 shows areas where one or more of the above groundwater indicators were observed during stream surveys and headwater assessments.
Figure 44 Groundwater indicators observed in the Jock River Barrhaven catchment
3.3.11 Fish Community
The Jock River Barrhaven catchment is classified as a mixed community of warm and cool water recreational and baitfish fishery with 36 species observed. Figure 45 shows the sampling locations along the Jock River in the Barrhaven catchment.
Figure 45 Jock River Barrhaven catchment fish community
The following table contains a list of species observed in the watershed.
Fish species observed in Jock River Barrhaven catchment
RVCA electrosfishing site at Prince of Wales in the Jock River Barrhaven catchment
Smallmouth bass captured during the electrofishing sampling effort at Prince of Wales Drive in the Jock River - Barrhaven catchment
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 46 shows that Jock River in the Barrhaven catchment had two weir barriers at the time of the survey in 2015. One is the seasonal barrier known as the Hearts Desire weir and the other is a low level crossing upstream of Highway 416. A debris dam was observed on a headwater system within the catchment.
Figure 46 Migratory obstructions along Jock River in the Barrhaven catchment
3.3.13 Riparian Restoration
Figure 47 depicts the locations of various riparian restoration opportunities as a result of observations made during the stream surveys.
Figure 47 Riparian restoration opportunities along the Jock River in the Barrhaven catchment
3.3.14 Instream Restoration
Figure 48 depicts the locations of instream restoration opportunities as a result of observations made during the stream surveys.
Figure 48 Instream restoration opportunities along the Jock River in the Barrhaven catchment
3.4 Headwater Drainage Feature Assessment
3.4.1 Headwaters Sampling Locations
The RVCA Stream Characterization program assessed Headwater Drainage Features for the Jock River subwatershed in 2015. 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 2015 the program sampled 5 sites at road crossings in the Jock River Barrhaven catchment area (Figure 49).
Figure 49 Locations of the headwater sampling sites in the Jock River Barrhaven 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. Three features were classified as having been channelized, one feature was identified as a roadside drainage features and one feature was classified as natural. Figure 50 shows the feature type of the primary feature at the sampling locations.
Figure 50 Headwater feature types in the Jock River Barrhaven catchment
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 51 shows the observed flow conditions at the sampling locations in the Jock River Barrhaven catchment in 2015.
Figure 51 Headwater feature flow conditions in the Jock River Barrhaven catchment
A spring photo of the headwater sample site in the Jock River Barrhaven catchment located on Okeefe Court
3.4.4 Feature Channel Modifications
Channel modifications were assessed at each headwater drainage feature sampling location. Modifications include channelization, dredging, hardening and realignments. The Jock River Barrhaven catchment area had one site classified as having no channel modifications, one feature was classified as being hardened and two had mixed modifications. Figure 52 shows the channel modifications observed at the sampling locations for Jock River Barrhaven.
Figure 52 Headwater feature channel modifications in the Jock River Barrhaven 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 vegetated 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 in the Jock River Barrhaven catchment were classified being dominated by wetland and meadow. Figure 53 depicts the dominant vegetation observed at the sampled headwater sites in the Jock River Barrhaven catchment.
Figure 53 Headwater feature vegetation types in the Jock River Barrhaven 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 in Jock River Barrhaven were dominated by natural vegetation in the form of meadow and wetland vegetation. Figure 54 depicts the type of riparian vegetation observed at the sampled headwater sites in the Jock River Barrhaven catchment.
Figure 54 Headwater feature riparian vegetation types in the Jock River Barrhaven 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 55 depicts the degree of sediment deposition observed at the sampled headwater sites in the Jock River Barrhaven catchment.
Figure 55 Headwater feature sediment deposition in the Jock River Barrhaven 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. The sample locations in the Jock River Barrhaven catchment area ranged from moderate to extreme roughness conditions. Figure 56 shows the feature roughness conditions at the sampling locations in the Jock River Barrhaven catchment.
Figure 56 Headwater feature roughness in the Jock River Barrhaven catchment
4.0 Jock River-Barrhaven Catchment: Land Cover
Land cover and any change in coverage that has occurred over a six-year period is summarized for the Jock River-Barrhaven 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 Barrhaven Catchment Change
As shown in Table 10 and Figure 1, the dominant land cover type across the Barrhaven catchment in 2014 was settlement, followed by crop and pastureland, transportation, aggregates and woodland.
Land cover (2008 vs. 2014) in the Barrhaven catchment
* Does not include treed swamps ** Includes treed swamps
From 2008 to 2014, there was an overall change of 446 hectares (from one land cover class to another). Most of the change in the Barrhaven catchment is a result of the conversion of crop and pastureland to settlement and transportation (Figure 57).
Figure 57 Land cover change in the Barrhaven catchment (2014)
Table 11 provides a detailed breakdown of all land cover change that has taken place in the Barrhaven catchment between 2008 and 2014.
Land cover change in the Barrhaven catchment (2008 to 2014)
4.1.1 Barrhaven Catchment Change - Urban Area
As shown in Table 12, the dominant land cover type in the Urban Area of the Barrhaven catchment in 2014 was settlement, followed by crop and pastureland, transportation and woodland.
Land cover (2008 vs. 2014) in the Urban Area of Barrhaven catchment
* Does not include treed swamps ** Includes treed swamps
From 2008 to 2014, there was an overall change of 398 hectares from one land cover class to another, the majority of which can be attributed to the conversion of crop and pasture to settlement along with areas previously subjected to pre-development, site preparation activity being converted to commercial and residential development. Table 13 provides a detailed breakdown of all land cover change that has taken place in the Urban Area of the Barrhaven catchment between 2008 and 2014.
Land cover change in the Urban Area of Barrhaven catchment (2008 vs. 2014)
4.1.2 Barrhaven Catchment Change - Rural Area
As shown in Table 14, the dominant land cover type in the Rural Area of the Barrhaven catchment in 2014 was aggregate, followed by settlement, woodland, crop and pastureland and transportation.
Land cover in the Rural Area of Barrhaven catchment (2008 vs. 2014)
* Does not include treed swamps ** Includes treed swamps
From 2008 to 2014, there was an overall change of 48 hectares from one land cover class to another, the majority of which can be attributed to the conversion of crop and pasture to settlement. Table 15 provides a detailed breakdown of all land cover change that has taken place in the Rural Area of the Barrhaven catchment between 2008 and 2014.
Land cover change in the Rural Area of Barrhaven catchment (2008 vs. 2014)
4.2 Woodland Cover
In the Environment Canada Guideline (Third Edition) entitled “How Much Habitat Is Enough?” 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 Jock Rideau 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 specialized-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 58, eleven percent of the Barrhaven catchment contains 344 hectares of upland forest versus the 26 percent of woodland cover in the Jock River subwatershed. This is less 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.
Figure 58 Woodland cover and interior forest (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 specialized 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 Barrhaven catchment (in 2014), forty-five (46 percent) of the 97 woodland patches are very small, being less than one hectare in size. Another 47 (49 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 five (five percent of) woodland patches range between 20 and 100 hectares in size and may support a few area-sensitive species along with some edge intolerant species, but will be dominated by edge tolerant species.
No patch exceeds the 100 plus hectare size needed to support most forest dependent, area sensitive birds and which are large enough to support approximately 60 percent of edge-intolerant species. No 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 27 ha) has been observed in the overall woodland patch area between the two reporting periods with most change occurring in the 1 to 20 and 20 to 50 hectare woodland patch size class ranges.
Woodland patches in the Barrhaven catchment (2008 and 2014)
*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 Barrhaven catchment (in 2014), the 97 woodland patches contain 11 forest interior patches (Figure 58) that occupy less than one percent (22 ha.) of the catchment land area (which is less than the three percent of interior forest in the Jock 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.
All 11 patches have less than 10 hectares of interior forest, four of which have small areas of interior forest habitat less than one hectare in size. Between 2008 and 2014, there was an overall loss of one hectare of interior forest habitat in the catchment (Table 17).
Woodland interior in the Barrhaven catchment (2008 and 2014)
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 stabilization 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.
Using the same dataset, it is estimated that pre-settlement (historic) wetland cover averaged 51 percent in the Jock River subwatershed versus the 24 percent of cover existing in 2014 (as summarized in Table 18).
Wetland cover in the Jock River subwatershed and Barrhaven catchment (Historic to 2014)
This decline in wetland cover is also evident in the Barrhaven catchment (as seen in Figure 59) where wetland was reported to cover 45 percent of the area prior to settlement, as compared to less than one percent in 2014. This represents a 99 percent loss of historic wetland cover and what remains (in 2014) falls far below the 40 percent historic wetland threshold cited in the Environment Canada Guideline for maintaining key ecological and hydrological functions. To maintain critical hydrological, ecological functions along with related recreational and economic benefits provided by these wetland habitats in the catchment, the Guideline recommends a “no net loss” approach for currently existing wetlands combined with efforts to work towards restoring upwards of 40 percent of the historic wetland coverage, where feasible.
Figure 59 Barrhaven catchment wetland cover
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 60 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, both sides of the shoreline of the Jock River and its tributaries in the Barrhaven catchment.
Figure 60 Natural and other riparian land cover in the Barrhaven catchment
This analysis shows that the riparian zone in the Barrhaven catchment in 2014 was comprised of crop and pastureland (36 percent), settlement (29 percent), woodland (20 percent), transportation (11 percent), aggregate (three percent) and wetland (one percent). Additional statistics for the Barrhaven catchment are presented in Table 19. Of particular interest is the observed increase in the area of "Settlement" and decrease in “Crop and Pastureland" along the shoreline of the Jock River and tributaries over a six year period.
Riparian land cover (2008 vs. 2014) in the Barrhaven catchment
5.0 Jock River-Barrhaven Catchment: Stewardship and Water Resources Protection
The RVCA and its partners are working to protect and enhance environmental conditions in the Jock River Subwatershed. Figure 61 shows the location of all stewardship projects completed in the Jock River-Barrhaven catchment along with sites identified for potential shoreline restoration.
5.1 Rural Clean Water Projects
From 2010 to 2015, two septic system replacements were constructed. Between 2004 and 2009, two septic system replacements, two livestock fencing projects, one well upgrade and one well decommissioning were finished and prior to 2004, five septic system replacements and three livestock fencing projects were completed, Four of these projects were completed within the 30 metre riparian zone of the Jock River. Total value of all 16 projects is $156,866 with $28,227 of that amount funded through grant dollars from the RVCA.
Figure 61 Stewardship site locations
5.2 Private Land Forestry Projects
The location of RVCA tree planting projects is shown in Figure 61. From 2010 to 2015, 300 trees were planted at one site and prior to 2004, 9,800 trees were planted at three sites. In total, 10,100 trees were planted resulting in the reforestation of six hectares. One of these projects was completed within the 30 metre riparian zone of the Jock River. No trees were planted in the catchment between 2004 and 2009. Total project value of all four projects is $50,135 with $23,421 of that amount coming from fundraising sources.
5.3 Shoreline Naturalization Projects
With the assistance of the RVCA’s Shoreline Naturalization Program, 475 trees and shrubs were planted to create an overall six metre long shoreline buffer at a total project value of $14,234.
5.4 Fish Habitat Restoration
Fish habitat compensation was required for the Barrhaven South development as a number of tributary watercourses were eliminated or modified to allow for development. A bypass pond was constructed off the main stem of the Jock River in 2008 to provide spawning and nursery habitat for northern pike and muskellunge in the spring and nursery and refugia habitat in the summer and fall. Under normal high water mark conditions, it provides approximately 9,000 meters square of habitat along with several small finger channels that extend from the larger pond to provide spawning habitat for northern pike. Post effectiveness monitoring work in 2010 revealed that thirteen species of fish were utilizing the habitat for spawning, nursery, rearing and feeding purposes, including northern pike. Subsequent fish sampling in 2015 confirmed that several species of fish continue to utilize the restored habitat within the pond feature.
Barrhaven South Fish Habitat Compensation location
5.5 Valley, Stream, Wetland and Hazard Lands
The Barrhaven catchment covers 31 square kilometres with 4.8 square kilometres (or 16 percent) of the drainage area being within the regulation limit of Ontario Regulation 174/06 (Figure 62), giving protection to wetland areas and river or stream valleys that are affected by flooding and erosion hazards.
Wetlands occupy 14.5 hectares (or less than one percent) of the catchment. Of these wetlands, 12.5 hectares (or 86 percent) are designated as provincially significant and included within the RVCA regulation limit. This leaves the remaining two hectares (or 14 percent) of wetlands in the catchment outside the regulated area limit.
Of the 50.3 kilometres of stream in the catchment, regulation limit mapping has been plotted along 22.1 kilometers of streams (representing 44 percent of all streams in the catchment). Some of these regulated watercourses (0.5 km or 1.0 percent of all streams) flow through regulated wetlands; the remaining 21.6 km (or 98 percent) of regulated streams are located outside of those wetlands. Plotting of the regulation limit on the remaining 28.2 km (or 56 percent) of streams requires identification of flood and erosion hazards and valley systems.
Within those areas of the Barrhaven catchment subject to the RVCA 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. Additionally, in the rapidly urbanizing areas of the Barrhaven catchment, significant effort is made through land use planning and development control processes and carefully planned stormwater management systems, initially guided by master drainage planning and integrated subwatershed planning, to meet the natural heritage and natural hazards policies presented in the City of Ottawa Official Plan. Also, within areas beyond the regulation limit, protection of the catchment’s watercourses is provided through the “alteration to waterways” provision of the regulation.
Figure 62 RVCA regulation limits
5.6 Vulnerable Drinking Water Areas
The Jock River-Barrhaven drainage catchment is considered to have 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. 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, please go to the Mississippi-Rideau Source Protection Region website at www.mrsourcewater.ca to view the Mississippi-Rideau Source Protection Plan.
6.0 Jock River-Barrhaven Catchment: Challenges/Issues
Surface chemistry water quality rating in the Jock River is “Fair” over two reporting periods (2004-2009 and 2010-2015). Frequent high nutrient concentrations and occasional exceedances of copper and aluminium contributed to the rating
Instream biological water quality conditions at the Jock River Barrhaven sample location range from “ Poor” to “Good” from 2004 to 2015 (using a grading scheme developed by Ontario Conservation Authorities in Ontario for benthic invertebrates) with an overall benthic invertebrate water quality rating of “Good” determined for this period
Effect of climate change on the hydrologic function (water budget) of the Jock River subwatershed and associated natural hazards (flood risk) posed to the built/urban areas of the catchment are not understood
Existing hydrological and geochemical datasets and assessments (academic, RVCA, others) are only recently available and/or are not being considered in the characterization of the numerous hydrologic functions of the Jock River subwatershed. Further, there is a dearth of hydrologic information (hydroperiod, groundwater/surface water interactions, geochemistry) about the wetlands that remain in the Jock River subwatershed
‘Natural’ vegetation covers 21percent of the riparian zone of the Jock River and its tributaries (Figure 60) and is below the recommended 30 metre wide, naturally vegetated target along 75 percent of the length of the catchment’s watercourses
Hearts Desire weir is a seasonal impediment to fish movement along the Jock River and can fragment/isolate fish populations
Woodlands cover 11 percent of the catchment and is below the 30 percent of forest cover that is identified as the minimum threshold for sustaining forest birds and other woodland dependent species (Figure 58)
Pre-settlement wetlands have declined by 99 percent and now cover less than one percent (14 ha.) of the catchment (Figure 59)
7.0 Jock River-Barrhaven Catchment: Opportunities/Actions
Investigate the source of possible pollutants along the Jock River in the catchment and consider implementing measures to reduce nutrient and metal loadings, such as improved storm water management in developed areas along with the incorporation of low impact development features to assist with storm water management
In rural areas, private landowners should consider taking advantage of The Rural Clean Water Programs which offer grants to landowners interested in implementing projects on their property that will help to protect and improve water quality:
- Homeowners may be interested in projects to repair, replace or upgrade their well or septic system, or addressing erosion through buffer plantings and erosion control
- Farmers can take advantage of a wide range of projects, including livestock fencing, manure storage, tile drainage control structures, cover crops, and many more.
Continue to coordinate environmental monitoring and reporting activities with the City of Ottawa
Use wetland restoration as a tool to improve surface water quality and help restore the hydrologic integrity of the Jock River and its tributaries
List, share and when possible, synthesize and use existing hydrological and geochemical datasets and assessment outcomes to facilitate the characterization of subwatershed and catchment hydrological functions. In addition, prepare guidance on best practices for the preparation of water budget assessments to better understand the hydrologic cycle requirements that occur at site specific scales; and share existing catchment and subwatershed scale water budget assessment outcomes
Promote the Rideau Valley Shoreline Naturalization Program to landowners to increase existing 21 percent of natural shoreline cover
Educate landowners about the value of and best management practices used to maintain and enhance natural shorelines and headwater drainage features
Work with the City of Ottawa to consistently implement current land use planning and development policies for water quality and shoreline protection (i.e., adherence to a minimum 30 metre development setback from water) adjacent to the Jock River and other catchment streams
Target shoreline restoration at sites identified in this report (shown as “Other riparian land cover” in Figure 60 and “Potential Riparian/Instream Restoration” in Figures 47/48) and explore other restoration and enhancement opportunities along the Jock River and its tributaries
Remove the fish migration barrier along the Jock River at Hearts Desire and improve riparian and instream conditions upstream of the structure
Promote the City of Ottawa’s Green Acres Reforestation Program to landowners to increase existing 11 percent of woodland cover
Encourage the City of Ottawa to strengthen natural heritage and water resources policies in official plans and zoning by-laws where shoreline, wetland, woodland cover and watercourse setbacks are determined to be at or below critical ecological thresholds. Information for this purpose is provided in the RVCA’s subwatershed and catchment reports
Explore ways and means to more effectively implement conditions of land-use planning and development approvals to achieve net environmental gains
Re-consider the RVCA’s approach to wetland regulation where there is an identified hydrologic imperative to do so (i.e., significant loss of historic wetland cover (see Figure 59) and/or seasonal, critically low baseflows in the Jock River and/or areas of seasonal flooding)
Full Catchment Report