Hydrogeology

Our Production Wells.

CWD has four (4) large-capacity production wells, drilled and constructed between 2010 and 2017. The production wells were constructed under CWD’s Well Replacement Program (2010-2017) and have replaced aging well infrastructure. The production wells withdraw water from the Abbotsford-Sumas Aquifer.

The production wells are located at Autumn and Lynden Well fields (at Lynden Street and Autumn Avenue, respectively). These wells operate in rotation, alternating between wellfields and between wells. The production wells supply water to meet an average day demand in the order of 3000 cubic metres per day, and with that supplying over 1.1 million cubic metres annually.

CWD’s Proactive Wells Monitoring & Preventative Maintenance Program.

Over the years CWD’s has developed a proactive well monitoring and maintenance program with as goal to ensure the wells’ productivity and longevity. CWD partners with their hydrogeological engineer since 2010, Dr. Ineke Kalwij, P.Eng. of Kalwij Water Dynamics Inc., to evaluate the well systems, and design and implement a customized preventative well maintenance program for each of the production wells. Timely assessments allow for prioritizing production wells when it comes to scheduling well preventative maintenance. For example, as a result of natural water chemistry, the production wells are prone to so-called “chemical encrustation” which entails the deposition of iron and manganese precipitates. This typically appears as (persistent) orange colored scaling on the well screen (or blackish if manganese precipitate is dominant), which, if left untreated, can plug the well screen and with that impact well productivity. Such scaling is typically removed by applying a specialized acid descaler (approved for use in groundwater wells by the National Science Foundation) which dissolves and dislodges the scaling.

CWD also systematically completes (in-house) Bacteriological Activity Reaction Tests (BART), completed by their water quality technician, Ryan Federau. BART is an accepted tool to assess the degree of naturally occurring biofouling in a well (i.e., microbial aggressivity). BART assesses microbial communities such as, among others, iron related bacteria, sulfur reducing bacteria and slime forming bacteria. Biofouling and chemical encrustation work in tandem.

The production wells have been operating successfully since their commissioning, and through the monitoring and maintenance program CWD is committed to proactively managing the groundwater source and related infrastructure.

Learn more about hydrogeology.