Project Description

Parks Canada needed help to determine whether groundwater was a feasible option as a potable water source for the planned expansion of the Frenchman Valley Campground in Grasslands National Park, Saskatchewan. ISL designed and completed a hydrogeological desktop assessment of potential source aquifers prior to drilling, to provide insight into their groundwater quantity and quality. Given the relatively low water demands (0.2 L/s), potential target aquifers were determined and the risks and benefits of both were outlined. This work concluded that deeper aquifers were likely not present. Therefore, we developed a procedure to thoroughly assess any shallower aquifers that looked like they could provide the required amounts of water. Concept renderings, detailed design and specifications were then completed in conjunction with the driller for review and approval by Parks Canada.

ISL oversaw the drilling, installation, development, and testing of a water source well (WSW). As expected, a much shallower aquifer was present that appeared to provide the required amount of groundwater. After communicating the results with Parks Canada, as well as the risks and benefits of continuing to drill deeper, a water well was completed in the shallow aquifer and a pumping test was conducted. The pumping test results indicated that the well would yield less than the water demand of 0.2 L/s, which was communicated with Parks Canada and next steps were discussed in conjunction with their limited budget. Rather than drilling deeper to explore for aquifers that may or may not have produced more water and would have likely been of worse quality, the decision was made in collaboration with Parks Canada to demobilize, analyze the data and discuss next steps.

Given the budget remaining by drilling shallower than expected, we were able to give a presentation to non-technical Parks Canada staff members that outlined the results of the program and suggested next steps. Parks Canada was able to make an informed decision to proceed with the recommendation the well that was installed and to conduct a longer-term pumping test to better evaluate the long-term well yield.

Following the longer-term test, another report was produced that outlined options for Parks Canada to provide treated potable water to the campground. As the well yielded a lower rate than was initially anticipated, we suggested tankage options to be able to continuously provide water to the visitors. This final step proved that the well is hydraulically disconnected from surface water and should be sustainable to produce water even in the dry summer months.

Challenges

• A step rate test could not be conducted because the flow rates could not be lowered or raised beyond 0.074 L/s
• The pumping test produced volumes less than the required water demand

Solutions

• A 7-hour constant rate test was conducted at 0.074 L/s to ensure the length of time was sufficient for long-term yield calculations to evaluate well efficiency, and abided by the Greater Sage Grouse noise mitigation measures
• ISL recommended the use of the WSW in conjunction with increased storage options and a treatment system
• A longer-term pumping test was recommended to further assess the sustainable yield of the well and was completed in 2018, using cost savings from drilling
• Work continued with ISL providing support on long-term monitoring of groundwater levels to further assess potential connections with surface infiltration