Drinking water in the community of Serpent River First Nation (located approximately 130 km west of Sudbury) was originally provided by four communal wells servicing isolated areas through separate water distribution systems. However, due to water quality concerns and overall condition of the systems, it was decided through a previously completed feasibility study to establish a single connected system to service the community, as well as to serve any future growth. Our firm was retained by the Serpent River First Nation (in association with OCWA project management group), to provide professional engineering and architectural services for detailed design, tendering, and contract administration of a new communal water treatment plant (WTP) using a surface water source and an expanded distribution system.
A program of water soundings and water sampling and testing of the source water from Aird Bay was completed as part of the initial study process. This was followed by an evaluation of possible treatment options. Tubular nanofiltration and modified slow sand filtration were short-listed as the most promising alternatives, based on a number of site-specific conditions such as raw water quality. The source water in Aird Bay of Lake Huron has relatively high colour, turbidity, and dissolved organic carbon. Due to the challenging raw water characteristics, it was decided to pilot test both filtration technologies under consideration. Tubular nanofiltration was ultimately selected as the preferred option, based on a comprehensive evaluation that included the pilot testing results as well as other considerations. The water is disinfected using a combination of ultraviolet for primary disinfection and chlorination for secondary disinfection.
Site selection criteria and evaluation details for the raw water intake, low lift water pumping station, WTP, and treated water booster station were documented in a design brief. The water treatment and distribution system includes two 332 m3 storage reservoirs and approximately 1.4 km of new watermain. We also prepared a hydraulic model of the entire distribution system using computer software in order to simulate various demand scenarios and evaluate the results against standard guidelines, in order to develop an overall design basis for distribution system upgrades.