Nichols Creek

Nichols Creek

Jock River Subwatershed Report 2016

NICHOLS CREEK 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 Nichols Creek catchment are a compilation of that work.

Catchment Facts Section 1.0
Surface Water Quality Conditions Section 2.0
Riparian Conditions Section 3.0
Land Cover Section 4.0
Land Stewardship and Water Resources Protection Section 5.0
Challenges/Issues Section 6.0
Actions/Opportunities Section 7.0

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 Nichols Creek catchment

 
Figure 1 Land cover in the Nichols Creek catchment

1.0 Nichols Creek Catchment: Facts

1.1 General/Physical Geography

Municipalities

  • Montague (13 km2; 28% of catchment)
  • Ottawa: (34 km2; 72% of catchment)

Geology/Physiography

  • The Nichols Creek Catchment resides with an extensive physiographic region known as the Smith Falls Limestone Plain. In this catchment, the limestone plain is discontinuously overlain by organic soils and localized areas of beach sands and gravels
  • In this catchment, bedrock consists of interbedded sandstone and dolostone of the March Formation in the southern parts and dolostone of the Oxford Formation in the northern parts

Topography

  • The ground surface ranges in elevation from approximately 140 masl at the head of Nichols Creek to approximately 97 masl at the catchment’s outlet

Drainage Area

  • 47 square kilometers; occupies eight percent of the Jock River subwatershed, one percent of the Rideau Valley watershed

Stream Length

  • Nichols Creek and tributaries: 62 km

1.2 Vulnerable Areas

Aquifer Vulnerability

  • The Mississippi-Rideau Source Protection initiative has mapped scattered parts of this catchment as a significant groundwater recharge areas and all the catchment as Highly Vulnerable Aquifer. Parts of Wellhead Protection Area (WHPA) D for the municipal wells in Kemptville underlie the southern half of this 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 Nichols Creek catchment
 

1.3 Conditions at a Glance

Water Quality

  • Surface chemistry water quality on Nichols Creek is “Fair” due to occasional high nutrient concentrations and bacterial pollution   
  • Instream biological water quality conditions at the Nichols Creek sample location range from “Fair” to “ Poor” 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 “Fairly Poor” determined for this period

Instream and Riparian

  • Overall instream and riparian condition for the Nichols Creek catchment as assessed by the stream characterization and headwater drainage feature assessment programs show that the Nichols Creek and its tributaries are in generally good condition. The majority of the system has low erosion levels and a healthy forested/wetland riparian corridor along Nichols Creek. Instream diversity of aquatic habitat is fairly complex in the upper reach of Nichols Creek, while the lower and middle reaches are dominated by wetland which is a very important wetland feature with high values that support catchment health

Thermal Regime

  • Warm/cool water thermal guild supporting the Jock River fishery

Fish Community

  • Twenty species of recreational and bait fish

Shoreline Cover Type (30 m. riparian area; 2014)

  • Wetland (77%)
  • Woodland (14%)
  • Crop and Pasture (5%)
  • Transportation (3%)
  • Meadow-Thicket (1%)
  • Settlement (<1%)

Land Cover Type (2014)

  • Wetland (43%)
  • Woodland (39%)
  • Crop and Pasture (9%)
  • Meadow-Thicket (4%)
  • Settlement (3%)
  • Transportation (2%)
  • Aggregate (<1%)
  • Water (<1%)

Land Cover Change (2008 to 2014)

  • Woodland (-8 ha)
  • Meadow-Thicket (-4 ha)
  • Crop and Pasture (-3 ha)
  • Aggregate (0 ha)
  • Transportation (0 ha)
  • Water (0 ha)
  • Settlement (+5 ha)
  • Wetland (+9 ha)

Significant Natural Features

  • Marlborough Forest Provincially Significant Wetland
  • Nichols Creek Provincially Significant Wetland
  • Pinery Road Provincially Significant Wetland
  • Richmond Fen Provincially Significant Wetland

Water Wells

  • 50 (approximately) operational private water wells in the catchment. Groundwater uses are mainly domestic but also include livestock watering

Aggregates

  • No Aggregate Resources Act licenses in the catchment. Very limited sand and gravel resources are of tertiary importance

Species at Risk (Elemental Occurrence)

  • Loggerhead Shrike, Spotted Turtle (Endangered)
  • Barn Swallow, Blanding’s Turtle (Threatened)
  • Eastern Milksnake, Snapping Turtle (Special Concern)

1.4 Catchment Care

Stewardship

  • Twelve stewardship projects undertaken (see Section 5)

Environmental Monitoring

  • 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 Nichols Creek (see Section 3.3.11)
  • Stream characterization survey on Nichols Creek in 2015, working upstream to the headwaters from the mouth of the creek where it empties into the Jock 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 chemistry information is available from the Ontario Geological Survey for a well located in this catchment

Environmental Management

  • Development along Nichols Creek and in and adjacent to the Provincially Significant Wetlands in the catchment (Marlborough Forest, Nichols Creek, Pinery Road, Richmond Fen ) are 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
  • No active Permit To Take Water (PTTW) and no Environmental Compliance Approvals issued in the catchment

2.0 Nichols Creek Catchment: Surface Water Quality Conditions

Surface water quality conditions in the Nichols Creek Catchment are monitored by the City of Ottawa 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 1 Water quality monitoring site in the Nichols Creek catchment
Figure 2 Water quality monitoring site in the Nichols Creek catchment

2.1 Nichols Creek Water Quality Rating

The RVCA's water quality rating for Nichols Creek (site CK76-01) is “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. There is limited data available at this site prior to 2010, therefore only information for the 2010-2015 period will be discussed. Table 1 shows the overall rating for the monitored surface water quality site within the Nichol’s Creek Catchment and Table 2 outlines the Water Quality Index (WQI) scores and their corresponding ratings.

There is one monitored water quality site on Nichols Creek within this catchment (CK76-01, Figure 2). The score at this site is largely influenced by occasional high nutrient concentrations and bacterial pollution. For more information on the CCME WQI, please see the Jock River Subwatershed Report.

Table 1 Water Quality Index rating for the Nichols Creek Catchment
Sampling SiteLocation 2010-2015Rating
CK76-01Nichols Creek upstream of O'Neil Rd culvert, north east of Dwyer Hill Rd.78FAIR
 
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

2.2 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) and ammonia (NH3) are used as secondary indicators of nutrient loading. RVCA uses a guideline of 0.500 mg/l to assess TKN[1] 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 Nichols Creek catchment and show the proportion of results that meet the guidelines.

Table 3 Summary of total phosphorus results for the Nichols Creek catchment, 2010-2015
Total Phosphorous 2010-2015
SiteAverage (mg/l)Below GuidelineNo. Samples
CK76-010.01298%59
 
Table 4 Summary of total Kjeldahl nitrogen results for the Nichols Creek catchment from 2010-2015. Highlighted values indicate average concentrations exceed the guideline
Total Kjeldahl Nitrogen 2010-2015
SiteAverage (mg/l)Below GuidelineNo. Samples
CK76-010.60624%59
 
Table 5 Summary of ammonia results for the Nichols Creek catchment from 2010-2015
Ammonia 2010-2015
SiteAverage (mg/l)Below GuidelineNo. Samples
CK76-010.024100%59
 

Monitoring Site CK76-01

TP results seldom exceeded the PWQO at site CK76-01. Ninety-eight percent of samples were below the guideline (Figure 3). The average TP concentration was below the objective at 0.012 mg/l as shown in Table 3.

The bulk of TKN results were elevated (Figure 4); only 24 percent of samples were below the guideline in the 2010-2015 period. The average concentrations exceeded the guideline at 0.606 mg/l (Table 4).

The results for NH3 indicate that exceedances occurred occasionally. Seventy-one percent of results were below the guideline in 2010-2015 reporting period (Figure 5). The average NH3 concentration was 0.024 mg/l (Table 5) and just exceeds the PWQO.

Figure 2 Total phosphorous concentrations in Nichols Creek, 2010-2015
Figure 3 Total phosphorous concentrations in Nichols Creek, 2010-2015
Figure 3 Total Kjeldahl nitrogen concentrations in Nichols Creek, 2010-2015
Figure 4 Total Kjeldahl nitrogen concentrations in Nichols Creek, 2010-2015
Figure 4 Ammonia concentrations in the Nichols Creek, 2010-2015
Figure 5 Ammonia concentrations in the Nichols Creek, 2010-2015

Summary

Occasional nutrient enrichment is a feature in this reach of Nichols Creek. The elevated TKN concentrations and moderate NH3 results provide evidence that elevated nutrients may be a natural feature in this part of the creek, and are likely associated with the large wetland areas.  Occasional exceedances of both NH3 and TP indicate that some nutrient loading may occur from upstream anthropogenic sources such as fertilizer use, agricultural activities and storm water runoff. Elevated nutrients may result in nutrient loading downstream and to the Jock 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 should be employed wherever possible to limit nutrient loading to the waterbody.

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[2] for the monitored site on the Nichol’s Creek within this 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 2010-2015 is shown in Figure 6.

Table 6 Summary of E. coli results for Nichols Creek, 2010-2015
E. coli 2010-2015
SiteGeometric Mean (CFU/100ml)Below GuidelineNo. Samples
CK76-013373%59
 
 

Monitoring Site CK76-01

Elevated E. coli counts at site CK76-01 were an occasional occurrence. The proportion of samples below the guideline was 73 percent (Figure 6). The geometric mean was 33 CFU/100ml (Table 6), and well below the PWQO of 100 CFU/100ml.

Figure 5 Geometric mean of E. coli results in the Nichols Creek, 2010-2015
Figure 6 Geometric mean of E. coli results in the Nichols Creek, 2010-2015
Summary

Bacterial pollution does not appear to be a significant problem at this site, the count at the geometric mean is well below the PWQO and the majority of samples do not exceed the guideline. Best management practices such as enhancing shoreline buffers, minimizing storm water runoff and restricting livestock access to creeks should be employed wherever possible to help to protect this reach of Nichols Creek into the future.


1No 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

2A 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

3.0 Nichols Creek Catchment: Riparian Conditions

3.1 Nichols Creek Overbank Zone

3.1.1 Riparian Buffer Width Evaluation

Figure 7 demonstrates the buffer conditions of the left and right banks separately. Nichols Creek had a buffer of greater than 30 meters along 98 percent of the left bank and 100 percent of the right bank.

Figure XX Riparian Buffer Evaluation along Nichols Creek
Figure 7 Riparian Buffer Evaluation along Nichols Creek

3.1.2 Ripariain 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 8). The riparian buffer zone along the Nichols Creek was found to be dominated by forest and wetland conditions along the riparian corridor.

Figure XX Riparian buffer alterations along Nichols Creek
Figure 8 Riparian buffer alterations along Nichols Creek

3.1.3 Adjacent Land Use

The RVCA’s Stream Characterization Program identifies six different land uses along Nichols Creek (Figure 9). 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 97 percent of the stream, characterized by forest, scrubland, meadow and wetland. Wetland habitat was dominant in the adjacent lands along Nichols Creek at 63 percent. The remaining land use consisted of abandoned agriculture and residential areas.

Figure XX Land Use along Nichols Creek
Figure 9 Land Use along Nichols Creek

3.2 Nichols 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 Nichols Creek had low levels of erosion along the system (Figure 10).

Figure XX Erosion levels along Nichols Creek
Figure 10 Erosion levels along Nichols 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 11 shows that Nichols Creek had low levels of undercut banks along the majority of the system with a few specific locations having moderate levels of undercut banks observed.

Figure XX Undercut stream banks along Nichols Creek
Figure 11 Undercut stream banks along Nichols 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 1m above the water surface. Figure 12 shows low to moderate levels of stream shading along Nichols Creek.

Figure XX Stream shading along Nichols Creek
Figure 12 Stream shading along Nichols Creek

3.2.4 Instream Woody Debris

Figure 13 shows that the majority of Nichols Creek had low to moderate levels of instream woody debris in the form of branches and trees along the system. Instream woody debris is important for fish and benthic invertebrate habitat, by providing refuge and feeding areas.

Figure XX Instream woody debris along Nichols Creek
Figure 13 Instream woody debris along Nichols Creek

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 14 shows the system has low levels of overhanging branches and trees along Nichols Creek.

Figure XX Overhanging trees and branches along Nichols Creek
Figure 14 Overhanging trees and branches along Nichols 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 15 shows 80 percent of Nichols Creek remains “unaltered” with no anthropogenic alterations. Eighteen percent of Nichols Creek was classified as natural with minor anthropogenic changes while only two percent was considered altered.

Figure XX Anthropogenic alterations along Nichols Creek
Figure 15 Anthropogenic alterations along Nichols Creek

3.3 Nichols 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 O'Neil Road site on Nichols Creek 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.

O'Neil Road sample location
O'Neil Road sample location
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 Nichols Creek catchment sample location at O’Neil Road are summarized by year from 2004 to 2015. “Fair” to “Poor” water quality conditions was observed at the Nichols Creek sample location (Figure 16) using a grading scheme developed by Conservation Authorities in Ontario for benthic invertebrates.

Figure xx Hilsenhoff Family Biotic Index at the Nichols Creek O’Neil Road sample location
Figure 16 Hilsenhoff Family Biotic Index at the Nichols Creek O’Neil Road 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 Nichols Creek site is reported to have “Fair” family richness (Figure 17).

Figure xx Family Richness at the Nichols Creek O’Neil Road sample location
Figure 17 Family Richness at the Nichols Creek O’Neil Road sample location
EPT

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. The community structure is typically dominated by species that are moderately tolerant and tolerant to poorer water quality conditions. As a result, the EPT indicates that the Nichols Creek sample location is reported to have “Fair” to “Poor” water quality (Figure 18) from 2004 to 2015.

Figure xx EPT at the Nichols Creek O’Neil Road sample location
Figure 18 EPT at the Nichols Creek O’Neil Road sample location
Conclusion

Overall the Nichols Creek sample location aquatic habitat conditions from a benthic invertebrate perspective is considered “Fairly Poor” from 2004 to 2015 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 Nichols Creek (Figure 19). Regions with increased habitat complexity were observed in the lower to upper reaches of the system within the catchment.

Figure XX Habitat complexity along Nichols Creek
Figure 19 Habitat complexity along Nichols 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 20 shows the overall presence of various substrate types observed along Nichols Creek. Substrate conditions were highly diverse along Nichols Creek with all substrate types being recorded at various locations along the creek. Figure 21 shows the dominant substrate type observed for each section surveyed along Nichols Creek.

Figure XX Instream substrate along Nichols Creek
Figure 20 Instream substrate along Nichols Creek
Figure XX shows the dominant substrate type along Nichols Creek
Figure 21 shows the dominant substrate type along Nichols Creek

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/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 xx shows that Nichols Creek is highly variable; 23 percent consists of runs, 7 percent riffles and 70 percent pools. Figure 22 shows where the riffle habitat areas were observed along Nichols Creek.

Figure XX Instream morphology along Nichols Creek
Figure 22 Instream morphology along Nichols 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
  • 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 98% of the sections surveyed, algae was observed in 68% of sections, while free floating plants were observed in 11% of surveyed sections. Broad leaved emergents were observed in 32% of sections, submerged plants in 93%, floating plants in 98% and robust emergents in 86% of sections surveyed. Figure 23 depicts the plant community structure for Nichols Creek. Figure xx shows the dominant vegetation type observed for each section surveyed along the Nichols Creek catchment.

Figure xx Vegetation type along Nichols Creek
Figure 23 Vegetation type along Nichols Creek
Figure XX Dominant vegetation type along Nichols Creek
Figure 24 Dominant vegetation type along Nichols 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 25 demonstrates that Nichols Creek reach had normal to common levels of vegetation recorded at 51 percent of stream surveys. Extensive levels of vegetation were observed along 34 percent of the systems length and were consistent with wetland areas dominated by European Frogbit.

Figure xx Instream vegetation abundance along Nichols Creek
Figure 25 Instream vegetation abundance along Nichols 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. Ninety five percent of the sections surveyed along Nichols Creek reach had invasive species. The invasive species observed in the Nichols Creek reach were European frogbit, poison/wild parsnip, phragmites and purple loosestrife. 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 26).

Figure XX Invasive species abundance along Nichols Creek
Figure 26 Invasive species abundance along Nichols 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 27 shows that the dissolved oxygen in Nichols Creek was predominantly below the threshold for warmwater biota along most of the system. The average dissolved oxygen levels observed within Nichols Creek was 3.14mg/L.

Figure XX Dissolved oxygen ranges in Nichols Creek
Figure 27 Dissolved oxygen ranges in Nichols 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 Nichols Creek catchment was 419.95 µs/cm. Figure 28 shows the conductivity readings for Nichols Creek.

Figure XX Specific conductivity ranges in Nichols Creek
Figure 28 Specific conductivity ranges in Nichols 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 the Nichols Creek catchment averaged 7.45 thereby meeting the provincial standard (Figure 29).

Figure XX pH ranges in Nichols Creek
Figure 29 pH ranges in Nichols 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 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:

  1. <100% Saturation / <6.0 mg/L Concentration. Oxygen concentration and saturation are not sufficient to support aquatic life and may represent impairment
  2. >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.
  3. <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.
  4. >100% Saturation / 6.0-9.5 mg/L Concentration. Oxygen concentration and saturation levels are optimal for warm water biota.
  5. <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.
  6. >100% Saturation / >9.5 mg/L Concentration. Oxygen concentration and saturation levels are optimal for cold water biota.
Figure XX A bivariate assessment of dissolved oxygen concentration (mg/L) and saturation (%) in Nichols Creek
Figure 30 A bivariate assessment of dissolved oxygen concentration (mg/L) and saturation (%) in Nichols Creek

Dissolved oxygen conditions on the Nichols Creek catchment are generally below levels to support warm and coolwater species (Figure 30). Dissolved oxygen conditions are lower in most reaches which are dominated by wetland habitat. Oxygen levels in wetland habitats are typically lower than they are in areas where the substrate is dominated by cobble and riffle habitat.

3.3.8.5 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 along the majority of Nichols Creek, however there were elevated areas in the middle reach where two tributaries enter the main stem of Nichols Creek (Figure 31).

Figure XX Relative specific conductivity levels along Nichols Creek
Figure 31 Relative specific conductivity levels along Nichols 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 32 shows where the thermal sampling sites were located along Nichols Creek. Analysis of the data collected indicates that Nichols Creek catchment is classified as a warm water system with cool water reaches (Figure 33).

Figure XX Temperature logger locations in the Nichols Creek catchment
Figure 32 Temperature logger locations in the Nichols Creek catchment
Figure XX Temperature logger data for the two sites in the Nichols Creek catchment
Figure 33 Temperature logger data for the two sites in the Nichols Creek 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

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 34 shows areas where one or more of the above groundwater indicators were observed during stream surveys and headwater assessments.

Figure XX Groundwater indicators observed in the Nichols Creek catchment
Figure 34 Groundwater indicators observed in the Nichols Creek catchment

3.3.11 Fish Community

The Nichols Creek catchment is classified as a mixed community of warm and cool water recreational and baitfish fishery with 20 species observed. Figure 35 shows the sampling locations along Nichols Creek.

Figure XX Fish community sampling results along Nichols Creek
Figure 35 Fish community sampling results along Nichols Creek

The following table contains a list of species observed in the watershed.

Table 7 Fish species observed in the Nichols Creek catchment
Fish SpeciesFish codeFish SpeciesFish code
banded killifishBaKilfathead minnowFhMin
blackchin shinerBcShifinescale daceFsDac
blacknose shinerBnShigolden shinerGoShi
bluntnose minnowBnMinhornyhead chubHhChu
brassy minnowBrMinIowa darterIoDar
brook sticklebackBrStinorthern pearl dacePeDac
brown bullheadBrBulnorthern redbelly daceNRDac
central mudminnowCeMudpumpkinseedPumpk
common shinerCoShirock bassRoBas
creek chubCrChuwhite suckerWhSuc
Fish sampling location along Nichols Creek
Fish sampling location along Nichols Creek

3.3.12 Migratory Obstructions

It is important to know locations of migratory obstructions because these can prevent fish from accessing important spawning and rearing habitat. Migratory obstructions can be natural or manmade, and they can be permanent or seasonal. Figure 36 shows that Nichols Creek catchment had several beaver dams, a debris dam and two natural grade barriers identified along Nichols Creek at the time of the survey in 2015.

Figure XX Migratory obstructions in the Nichols Creek catchment
Figure 36 Migratory obstructions in the Nichols Creek catchment

3.4 Headwater Drainage Feature Assessment

3.4.1 Headwater 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 4 sites at road crossings in the Nichols Creek catchment area (Figure 37).

Figure XX Location of the headwater sampling site in the Nichols Creek catchment
Figure 37 Location of the headwater sampling site in the Nichols Creek 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 Nichols Creek catchment are primarily classified as wetland with one feature classified as channelized. Figure 38 shows the feature type of the primary feature at the sampling locations.

Figure XX Headwater feature types in the Nichols Creek catchment
Figure 38 Headwater feature types in the Nichols Creek catchment
A spring photo of the headwater sample site in the Nichols Creek catchment located on Derry Side Road
A spring photo of the headwater sample site in the Nichols Creek catchment located on Derry Side Road
A summer photo of the headwater sample site in the Nichols Creek catchment located on Derry Side Road
A summer photo of the headwater sample site in the Nichols Creek catchment located on Derry 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 39 shows the observed flow condition at the sampling locations in the Nichols Creek catchment in 2015.

Figure XX Headwater feature flow conditions in the Nichols Creek catchment
Figure 39 Headwater feature flow conditions in the Nichols Creek catchment

3.4.4 Headwater Feature Channel Modifications

Channel modifications were assessed at each headwater drainage feature sampling location. Modifications include channelization, dredging, hardening and realignments. The Nichols Creek catchment area had three features with no channel modifications observed and one site as having been recently dredged. Figure 40 shows the channel modifications observed at the sampling locations for Nichols Creek.

Figure XX Headwater feature channel modifications in the Nichols Creek catchment
Figure 40 Headwater feature channel modifications in the Nichols Creek 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 wildlife habitat. The following classifications are evaluated no vegetation, lawn, wetland, meadow, scrubland and forest. Figure 41 depicts the dominant vegetation observed at the sampled headwater sites in the Nichols Creek catchment.

Figure XX Headwater feature vegetation types in the Nichols Creek catchment
Figure 41 Headwater feature vegetation types in the Nichols Creek 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. Figure 42 depicts the type of riparian vegetation observed at the sampled headwater sites in the Nichols Creek catchment.

Figure XX Headwater feature riparian vegetation types in the Nichols Creek catchment
Figure 42 Headwater feature riparian vegetation types in the Nichols Creek 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. Sediment deposition ranged from none to moderate for the headwater sites sampled in the Nichols Creek catchment area. Figure 43 depicts the degree of sediment deposition observed at the sampled headwater sites in the Nichols Creek catchment.

Figure XX Headwater feature sediment deposition in the Nichols Creek catchment
Figure 43 Headwater feature sediment deposition in the Nichols Creek 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 for aquatic organisms. Figure 44 shows the feature roughness conditions at the sampling location in the Nichols Creek catchment.

Figure Headwater feature roughness in the Nichols Creek catchment
Figure 44 Headwater feature roughness in the Nichols Creek catchment

4.0 Nichols Creek Catchment: Land Cover

Land cover and any change in coverage that has occurred over a six-year period is summarized for the Nichols Creek 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 Nichols Creek Catchment Change

As shown in Table 8 and Figure 1, the dominant land cover types across the Nichols Creek catchment in 2014 were wetland and woodland.

Table 8 Land cover (2008 vs. 2014) in the Nichols Creek catchment
Land Cover20082014Change - 2008 to 2014
AreaAreaArea
HaPercentHaPercentHaPercent
Wetland **20134320224390
>Evaluated(1638)(35)(1638)(35)(0)(0)
>Unevaluated(375)(8)(384)(8)(9)(0)
Woodland*185840185039-8-1
Crop and Pasture43894359-30
Meadow-Thicket18341794-40
Settlement1162121351
Transportation85285200
Aggregate9<19<100
Water3<13<100
* Does not include treed swamps ** Includes treed swamps

From 2008 to 2014, there was an overall change of 23 hectares (from one land cover class to another). Most of the change in the Nichols Creek catchment is a result of the conversion of woodland to wetland and crop and pastureland reverting to woodland along with woodland being cleared for settlement (Figure 45).

Figure xx Land cover change in the Nichols Creek catchment (2014)
Figure 45 Land cover change in the Nichols Creek catchment (2014)

Table 9 provides a detailed breakdown of all land cover change that has taken place in the Nichols Creek catchment between 2008 and 2014.

Table 9 Land cover change in the NIchols Creek catchment (2008 to 2014)
Land CoverChange - 2008 to 2014
Area
Ha.Percent
Wooded Area to Unevaluated Wetland8.937.8
Crop and Pasture to Wooded Area4.720.0
Wooded Area to Settlement4.418.5
Meadow-Thicket to Crop and Pasture2.812.1
Crop and Pasture to Settlement1.35.5
Meadow-Thicket to Wooded Area0.83.5
Settlement to Transportation0.31.2
Transportation to Settlement0.21.1
Wooded Area to Crop and Pasture<0.1<0.1
Meadow-Thicket to Settlement<0.1<0.1

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 Jock 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 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 46, 42 percent of the Nichols Creek catchment contains 1850 hectares of upland forest and 117 hectares of lowland forest (treed swamps) versus the 26 percent of woodland cover in the Jock 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.

Figure xx Woodland cover and forest interior (2014)
Figure 46 Woodland cover and forest interior (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 Nichols Creek catchment (in 2014), forty-five (35 percent) of the 130 woodland patches are very small, being less than one hectare in size. Another 64 (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 21 (16 percent of) woodland patches range between 20 and 292 hectares in size. Sixteen 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, five (four percent) of the 130 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 top 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 10 presents a comparison of woodland patch size in 2008 and 2014 along with any changes that have occurred over that time. A decrease (of eight ha) has been observed in the overall woodland patch area between the two reporting periods with most change occurring in the 20 to 50 hectare woodland patch size class range.

Table 10 Woodland patches in the Nichols Creek catchment (2008 and 2014)
Woodland Patch Size Range (ha)Woodland* PatchesPatch Change
200820142008 to 2014
NumberAreaNumberAreaNumberArea
CountPercent HaPercentCountPercent HaPercentCountHa
Less than 1 4535171453517100
1 to 20614833117644935818327
20 to 501193231610828915-1-34
50 to 100654242165423210-1
100 to 200435903043588300-2
Greater than 2001<1290151<12921502
Totals128100197510013010019671002-8
*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 Nichols Creek catchment (in 2014), the 130 woodland patches contain 79 forest interior patches (Figure 46) that occupy eight percent (379 ha.) of the catchment land area (which is greater 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.

Most patches (66) have less than 10 hectares of interior forest, 46 of which have small areas of interior forest habitat less than one hectare in size. The remaining 13 patches contain interior forest between 10 and 53 hectares in area. Between 2008 and 2014, there has been a large change in the number of woodland patches containing smaller areas (below 10 hectares) of interior habitat with an overall loss of nine hectares in the catchment (Table 11), suggesting an increase in forest fragmentation over the six year period.

Table 11 Woodland Interior in the Nichols Creek catchment (2008 and 2014)
Woodland Interior Habitat Size Range (ha)Woodland InteriorInterior Change
200820142008 to 2014
NumberAreaNumberAreaNumberArea
CountPercentHaPercentCountPercent HaPercentCountHa
Less than 1 113331465892356
1 to 101030277202576201049
10 to 3092716242111418950227
30 to 50133180000-1-31
50 to 100261654223105280-60
Totals331003881007910037910046-9
 

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 12).

Table 12 Wetland cover in the Jock River subwatershed and Nichols Creek catchment (Historic to 2014)
Wetland Cover Pre-settlement20082014Change - Historic to 2014
Area  Area  Area  Area  
Ha Percent Ha Percent Ha Percent Ha Percent 
Nichols Creek264856201343202243-626-24
Jock River285275113282241323024-15297-54
Rideau Valley13411535------8207621-52039-39
 

This decline in wetland cover is also evident in the Nichols Creek catchment (as seen in Figure 47) where wetland was reported to cover 56 percent of the area prior to settlement, as compared to 43 percent in 2014. This represents a 24 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.

Figure xx Nichols Creek catchment wetland cover
Figure 47 Nichols Creek 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 48 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 Nichols Creek catchment.

Figure xx Natural and other riparian land cover in the Nichols Creek catchment
Figure 48 Natural and other riparian land cover in the Nichols Creek catchment

This analysis shows that the riparian zone in the Nichols Creek catchment in 2014 was comprised of wetland (77 percent), woodland (14 percent), crop and pastureland (five percent), transportation (three percent), meadow-thicket (one percent) and settlement (less than one percent). Additional statistics for the Nichols Creek catchment are presented in Table 13 and show that there has been very little change in shoreline cover from 2008 to 2014.

Table 13 Riparian land cover (2008 vs. 2014) in the Nichols Creek catchment
Riparian Land Cover20082014Change - 2008 to 2014
AreaAreaArea
Ha.Percent Ha.PercentHa.Percent
Wetland278762807721
> Unevaluated(221)(61)(221)(61)(0)(0)
> Evaluated(57)(15)(59)(16)(2)(1)
Woodland53145114-20
Crop & Pasture205195-10
Transportation10310300
Meadow-Thicket212100
Settlement2<12<100

5.0 Nichols Creek 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 49 shows the location of all stewardship projects completed in the Nichols Creek catchment along with sites identified for potential shoreline restoration.

5.1 Rural Clean Water Projects

From 2004 to 2009, one livestock fencing project was completed and prior to 2004, one septic system was replaced. No projects were undertaken between 2010 and 2015. Total value of the two projects is $7,170 with $5,170 of that amount funded through grant dollars from the RVCA.

Figure xx Stewardship and potential restoration locations  
Figure 49 Stewardship site locations

5.2 Private Land Forestry Projects

The location of RVCA tree planting projects is shown in Figure 49. Between 2004 and 2009, 200 trees were planted at one site and prior to 2004, 73,870 trees were planted at nine sites, resulting in the reforestation of 38 hectares. No projects were undertaken between 2010 and 2015. Total value of all ten projects is $222,558 with $85,518 of that amount coming from various fundraising sources.

5.3 Valley, Stream, Wetland and Hazard Lands

The Nichols Creek catchment covers 47 square kilometres with 26.9 square kilometres (or 57 percent) of the drainage area being within the regulation limit of Ontario Regulation 174/06 (Figure 50), giving protection to wetland areas and river or stream valleys that are affected by flooding and erosion hazards.

Wetlands occupy 20.2 sq. km. (or 43 percent) of the catchment. Of these wetlands, 16.5 sq. km (or 81 percent) are designated as provincially significant and included within the RVCA regulation limit. This leaves the remaining 3.7 sq. km (or 19 percent) of wetlands in the catchment outside the regulated area limit.

Of the 62 kilometres of stream in the catchment, regulation limit mapping has been plotted along 46.3 kilometers of streams (representing 75 percent of all streams in the catchment). Some of these regulated watercourses (40.3 km or 65 percent of all streams) flow through regulated wetlands; the remaining 6 km (or 13 percent) of regulated streams are located outside of those wetlands. Plotting of the regulation limit on the remaining 15.6 km (or 25 percent) of streams requires identification of flood and erosion hazards and valley systems.

Within those areas of the Nichols Creek 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.

Figure xx RVCA regulation limits
Figure 50 RVCA regulation limits

5.4 Vulnerable Drinking Water Areas

The Nichols Creek 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 Nichols Creek Catchment: Challenges/Issues

Water Quality/Quantity

Surface chemistry water quality in Nichols Creek is “Fair” due to occasional high nutrient concentrations and bacterial pollution

Instream biological water quality conditions at the Nichols Creek sample location range from “Fair” to “ Poor” 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 “Fairly Poor” determined for this period

Natural hazard lands have not been identified

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

Land Cover

Pre-settlement wetlands have declined by 24 percent and now cover 43 percent (2023 ha.) of the catchment (Figure 47). Nineteen percent (385 ha.) of these wetlands remain unevaluated/unregulated and are 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

7.0 Nichols Creek Catchment: Opportunities/Actions

Water Quality/Quantity

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

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

Nichols Creek flood risks are to be studied as part of ongoing efforts to prepare flood plain mapping for the Jock River subwatershed

Headwaters/Instream/Shorelines

Promote the Rideau Valley Shoreline Naturalization Programs to landowners to increase 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 Township of Montague and 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 watercourses, including Nichols Creek                                 

Land Cover

Promote the City of Ottawa Green Acres Reforestation Program and the Rideau Valley Trees for Tomorrow Program to landowners to increase existing woodland cover

Encourage the Township of Montague and 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 enforce and 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 47) and/or seasonal, critically low baseflows in the Jock River and/or areas of seasonal flooding)

Full Catchment Report