AECOM Report B&W - N - City of Guelph

City of Guelph2008 Annual ReportClosed Eastview Road Landfill SiteSW16 is located at the storm sewer outlet on the southeast side of Eastview Road near the landfill entrance,and indicates the contributions (if any) of drainage from the southwest ditch to Hadati Creek. This site islocated downstream of the confluence with the Eastview Road ditch (SW2) and the southwest ditch (SW1).SW24 is located within the landfill site and receives runoff during wet weather events. A series of two rockcheck dams were installed in 1997 to allow suspended sediments to settle out of the runoff prior todischarging from the site. Three points were sampled at this station in 2008: SW24a (upstream of the checkdams), SW24m (between the check dams), and SW24 (downstream of the check dams). A comparison ofTotal Suspended Solids (TSS) concentrations of the three samples and the downstream station (SW4) isused to assess the effectiveness of the dams in reducing TSS discharged from this area.SW4 is located in a drainage ditch at the outlet of the wetland, downstream of SW24 and on the northwestside of Eastview Road.5.2.3 Downstream Surface Water StationsSW3A is downstream of the landfill in Hadati Creek, on the southeast side of Eastview Road. The resultsfrom this station are compared against the established Provincial Water Quality Objectives (PWQOs).5.3 2008 Sampling ProgramTotal precipitation during 2008 was 1,252 mm, which is higher than the long-term average annualprecipitation of 881 mm. January, February, March, June, July, August, September and December all hadsignificantly more precipitation than normal (at least > 28 mm/month), with April and October being the onlymonths with less than normal precipitation. The mean monthly temperature was 6.5°C, which is similar to thelong-term average mean temperature of 6.7°C.Evapotranspiration in 2008 was calculated to be 585.2 mm, which is slightly higher than the long-termaverage annual evapotranspiration of 566 mm. The 2008 water surplus (the amount of precipitationremaining after evapotranspiration is subtracted) available for runoff and infiltration was 667.2 mm, which issignificantly higher when compared with the long-term average of 316 mm. The range of annual watersurplus is estimated to be from 207 mm to 480 mm per year, thus the overall surplus water for 2008 wasmuch higher than the long-term range. In summary, 2008 would be considered significantly wetter than anormal year.The 2008 sampling program followed the protocol described by Gartner Lee Limited (2007). During theprescribed periods for sampling, four sampling events were attempted; all monitoring locations were sampledin the Spring Freshet, Summer Rain and Fall Rain (except for SW24, SW24a and SW24m). The SummerDry sampling event was unsuccessful due to insufficient surface water flow in the month of August. Thesesampling events are outlined in Table 9.(111414_2ra_apr29-09_city_of_guelph.doc) - 43 -