Question 7 of 7: Water Resource Management

Question 7: Water Resource Management (20 marks)

Question text not reproduced: the examination questions are © Engineers and Geoscientists BC. Open the official past paper (linked at the top of this page) to read the question, then follow the worked solution below.

Part (i) — Protecting a vulnerable drinking-water aquifer

Strategy 1 — wellhead and aquifer source protection (short and long term). Delineate the aquifer’s capture zone and establish a wellhead protection area with land-use controls: restrict and buffer activities within the recharge zone, control surface runoff so contaminated water cannot infiltrate (diversion, lined channels, retention of smelter site drainage), and require the smelter to manage its stormwater and air deposition (dust suppression, emission controls) so that acidifying and metal-bearing fallout does not reach the recharge area. In the short term this stops the immediate infiltration pathway; in the long term the land-use controls preserve recharge quality permanently.

Strategy 2 — monitoring, and diversification/managed recharge. Install a groundwater-quality monitoring network (sentinel wells between the smelter and the supply wells) with trigger levels for metals, pH and sulphate, so contamination is detected before it reaches the wells — the short-term protective measure. For long-term viability, reduce dependence on the single vulnerable aquifer by diversifying supply (a second source or interconnection), controlling pumping to avoid drawing the contaminated plume toward the wells, and considering managed aquifer recharge with clean water to maintain heads and dilute. Together these protect both the near-term safety and the multi-decade sustainability of the resource.

Part (ii) — Sustaining Vancouver’s water distribution infrastructure

Strategy 1 — asset management and proactive renewal. Over a 50-year life the distribution network ages and pipes fail. A formal asset-management program — inventory and condition assessment, criticality ranking, and a funded, risk-based main-replacement/rehabilitation schedule (cathodic protection, cured-in-place lining) — renews the system before failures cascade, and rate-setting that funds a renewal reserve keeps it sustainable rather than deferring the cost to a future crisis.

Strategy 2 — leak detection and water-loss (non-revenue water) control. Active leakage control — district-metered areas, pressure management, acoustic leak surveys and prompt repair — preserves both the water resource and the infrastructure (high pressures and undetected leaks accelerate pipe deterioration and washouts). Reducing non-revenue water defers capacity expansion and extends asset life, a demand-side complement to physical renewal.

Part (iii) — Sustaining Edmonton’s stormwater collection infrastructure

Strategy 1 — green/low-impact-development (LID) stormwater management. Reduce the runoff volume and peak the pipes must carry by managing water where it falls: bioswales, permeable pavement, retention/detention ponds, wetlands and rain gardens infiltrate and store runoff, easing hydraulic load on the collection system, improving discharge quality, and adapting to more intense storms under a changing climate over the 50-year horizon — often at lower whole-life cost than upsizing pipes.

Strategy 2 — inspection, maintenance and inflow/infiltration control with asset management. Sustain the buried network through regular CCTV inspection, sediment and debris cleaning, and repair/relining of deteriorated culverts and pipes, coupled with an asset-management renewal plan. Separating storm and sanitary flows and controlling inflow/infiltration prevents surcharging and basement flooding, keeping the system effective and protecting receiving waters (the North Saskatchewan River) throughout its service life.