Rockcliffe Existing Conditions Report
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· WC1: The channel morphology site erosion is evident throughout this · EC1: The channel morphology site length was 56 m. This site was the reach. Instream cover consisted of length was 40 m. This site is heavily furthest downstream site sampled extensive woody debris. forested. Connection to the Ottawa and is located just south of where the River at this location is blocked by the creek flows into the culvert that runs · EC4: The channel morphology site raised recreational trail. Ponded under the RCMP complex. The creek length was 40 m. The site was heavily water was observed upstream of the banks at this site are forested with a forested with a narrow channel cross- raised recreational trail both during thin section of riparian woodland. section. The flow regime can be baseflow and peak flow conditions. Exposed soils along the banks and characterized as having shallow water erosion sites are evident throughout depth but with higher flow velocities Photographic logs of each assessment site this reach. than EC5 due to the reduced channel (EC5- EC1) are included in Appendix D. width. Stream banks have improved General Findings Photographic logs of each assessment site vegetative cover and overall erosion (WC5- WC1) are included in Appendix D. sites are reduced, however The following sections describe the undercutting of the banks is evident. general findings of the DST (2013) Aquatic Eastern Creek Habitat Assessment Report Appendix D. · EC5: The channel morphology site · EC3: The channel morphology site Table 19 presents a summary of key length was 73 m. This site is the most length was 74 m. This site is a side findings and individual results. upstream site and was located north tributary to the main channel (flowing of the Rockcliffe Parkway culvert. EC5 from west of the main creek). The Active Channel is heavily forested with secondary side tributary is heavily forested and Both the Eastern and Western creek had growth deciduous forest. The flow was virtually dry during baseflow an active channel width ranging from 0.5 regime can be characterized as having periods. The channel cross-section is to 2.0 m with the Western Creek gradually shallow water depth and low flow wide and ill defined. increasing from upstream to downstream, velocity at the time of the assessment while the Eastern creek channel width · EC2: The channel morphology site (baseflow conditions) however the varied along its course. Maximum bank length was 44 m. This site was heavily channel planform is highly height ranged from approximately 450 mm forested with low banks. Overall EC2 straightened and the channel cross- to 700 mm in the Western creek and 350 does not demonstrate current signs section is in adjustment to the flows mm to 750 mm in the Eastern creek. from the Rockcliffe Parkway culvert. of erosion or instability. Exposed soils and stream bank 74 Aquafor Beech Ltd. August 2015 – Final Report EC3 EC1 consulting engineers 2150 THURSTON DRIVE, SUITE 203 OTTAWA, ONTARIO, K1G 5T9 TEL (613) 748-1415 FAX (613) 748-1356 www.dstgroup.com EC2 LEGEND: EC4 CREEK LOCATIONS EC5 OSAP SURVEY LOCATION SITE BOUNDARY WC1 WC2 WC3 NOTE: 1. THIS DRAWING SHALL BE READ IN CONJUNCTION WITH THE ASSOCIATED TECHNICAL REPORT. 2. SOURCE - GOOGLE EARTH WC4 WC5 0 09/08/13 FINAL A.M. REV DATE ISSUE APPROVAL PROJECT TITLE AQUATIC HABITAT ASSESSMENT: WESTERN AND EASTERN CREEKS, FORMER CFB ROCKCLIFFE DRAWING TITLE SITE PLAN DESIGNED BY SCALE A.M. N.T.S DRAWN BY DATE R.P. August 2013 PROJECT MANAGER PROJECT NO.: A.M. OE-OT-017184 FIGURE No.: FIGURE 2 Bank Angle creek ranged from 0 to 46 mm. In both found to have low to moderate levels of Overall, bank angles for both creeks range creeks the main channels were hydrated bank vegetative cover throughout its from 13° to 26°. The Western creek is along their entire length suggesting that length. Whereas, the Eastern Creek is characterized by higher bank angles these creeks are primarily groundwater characterized as having low to moderate (steeper banks) in the middle reaches as fed during baseflow conditions. This is levels of bank vegetation, it does display compared to the upstream and supported by the hydrogeological studies consistently high counts of instream cover downstream extents, while the Eastern (DST, June 2014). Overall, during baseflow (20 cover points/site), an important Creek displays shallower bank angles in conditions, both creeks can be component of aquatic habitat for fish the middle reaches and lower reaches. characterized as having shallow flow species. Cover is more varied in the depths and low flow velocities. Western creek with higher levels of instream cover observed at upstream Water Depth and Flow Bank Vegetation and Instream Cover locations as compared downstream. The water depth during baseflow In general, Western creek had more bank conditions in the Western creek ranged vegetative cover on average than the from 52 to 105 mm while the Eastern Eastern creek. The Eastern creek was Table 19: Aquatic Habitat Assessment Findings- Channel Characteristics L/R L/R Active Water Channel Hydraulic Max. Particle Instream Channel Bank Angles Site Channel Depth Depth Head (mm) (mm) Cover Points Slope (Degrees) width (m) (mm) (mm) WC5 0.55 52 458/466 0.59 28.32 33 0.27 16.88/16.47 WC4 1.31 88 648/691 0.36 13.14 14 0.45 22.64/24.15 WC3 1.02 105 693/572 1.36 49.09 34 0.38 24.56/20.71 WC2 1.54 61 703/686 2.05 98.50 51 0.46 24.89/24.30 WC1 1.77 76 485/531 1.14 114.75 30 0.34 17.54/19.21 EC5 1.84 30 732/756 0.17 72.00 21 0.49 25.74/26.40 EC4 0.52 26 465/524 0.45 106.40 20 0.35 17.05/18.97 EC3 1.82 0 447/474 0.0 19.26 24 0.29 16.53/17.42 EC2 0.98 25 357/353 0.16 2.09 18 0.22 13.26/13.09 EC1 1.95 46 525/575 0.05 55.56 19 0.38 18.99/20.85 76 Aquafor Beech Ltd. August 2015 – Final Report Bank Undercuts Water Temperature Macroinvertebrates Bank undercutting indicates locations Maximum summer water temperature was The 2013 assessment by DST also where active or historic bank erosion is or assessed by DST on July 24, 2013. considered the stream-bottom has occurred and is an indication of macroinvertebrate community, as these channel stability, state of adjustment, and Water temperature in the Western creek animals are an important link in the overall flow regime. was highest at the upstream but was aquatic food chain. considerably cooler in the deeper mid- In general, the Western Creek displayed reach sections of the creek (Table 21). The community of macroinvertebrates was few sever bank undercuts (Table 20), Lower mid-reach temperatures are likely found to be moderately diverse, ranging whereas the majority of the Eastern Creek influenced by a combination of factors from 9 to 15 taxa at each site, however displayed undercutting of the right bank. including temperature moderation from key indicator species were mostly absent. Other signs of erosion within the Eastern subsurface stormwater discharges, water The findings suggest that the overall Creek including slumping banks were also depth and heavy shade. habitat quality of the creeks varies from noted. Overall, it appears that moderate moderately good to moderately poor. levels of erosion are occurring along the In general, water temperature in the Most of the taxa found during the 2013 majority of the channel length of the Eastern Creek was highest at the surveys were relatively common taxa Eastern creek. Conversely, only a few downstream extent as compared to the which are either very tolerant or areas of moderate erosion within the upstream. Higher downstream water moderately tolerant to poor water quality Western creek were identified. temperatures are likely a result of and contamination. prolonged exposure to ambient air Table 20: Total Bank Undercuts temperature due shallow gradients and The limited number of macroinvertebrate Right Bank Site Left Bank (mm) the lack of an outlet to the Ottawa River at (mm) indicator species suggests that the best the raised pedestrian walkway. WC5 0 0 quality sites are WC5 and WC4 on the WC4 0 398 Western Creek and EC4 and EC3 on the WC3 150 80 Table 21: Water Temperature Water Temp. Air Temp. Eastern Creek. WC2 0 40 Site WC1 0 0 (°C) (°C) * WC5 17.5 EC5 10 1320 WC3 12.5 19.6-20.7 EC4 150 480 EC5 17.0 EC3 0 270 EC1 21.8 EC2 0 200 * http://climate.weather.gc.ca (accessed EC1 0 0 7/14) Aquafor Beech Ltd. August 2015 – Final Report 77 Fish and Fish Habitat throughout its length, even during context of proposed connections and baseflow conditions. Water levels were habitat creation activities. Western Creek low throughout the Eastern Creek during Sites in the Western Creek appear to baseflow conditions and few deeper pools Aquatic Species at Risk (SAR) provide marginal fish habitat that could be were present to support fish. Per the Preliminary Terrestrial Habitat suitable for some common fish species, Assessment for the Proposed Stormwater however no fish were encountered during The Eastern Creek generally had low levels Ponds at the Former CFB Rockcliffe (DST, the fish surveys. While adequate instream of in-stream cover, most of which was 2013) included in Appendix E the Ontario cover exists in the Western Creek woody debris and virtually no aquatic Stream Assessment Protocol (OSAP) (particularly in its lower sections), most of vegetation throughout its length.