The second step of a water supply integrity program is to complete baseline testing on the active domestic use water sources identified during the water source inventory. The testing will document the baseline water quality and quantity, where applicable, for the water sources on the reserve.
Communal domestic water supply sources typically have sufficient data from historical testing and sampling programs, and therefore the water supply integrity issues are likely to have already been identified and addressed. Therefore, the water supply integrity program focuses on the private water systems, primarily water wells, within the community that are not routinely tested or maintained.
For each private water supply well, a baseline yield test is conducted to document the drawdown of the groundwater level in the well in response to pumping at a sustained constant rate for 60 minutes. A flow-control valve is used to maintain a constant pumping rate and, if the well is accessible, a pressure transducer with datalogger is installed into the well to regularly monitor the groundwater level response to pumping. Once the pump is shut off, the recovery of the water level is monitored for an additional 60 minutes or until 90% recovery of the pre-pumping water level. The data collected, provides a baseline to which future issues regarding groundwater quantity, such as impacts from adjacent water usage, can be compared.
During the baseline yield test, untreated groundwater is monitored periodically for electrical conductivity (EC), pH, and temperature at a sampling point upstream of any water treatment system. Groundwater may be flowed through a gas separator to test for the presence of free gas, and observations such as water colour, odour, clarity and the presence of sediment will be recorded.
Near the end of the pumping portion of the baseline yield test, Waterline will collect water samples for analytical testing of general chemistry and microbiological parameters following standard quality assurance procedures. Other specific parameters identified in consultation with the First Nations community may also be included in the analytical program.
In addition to sampling water supply wells, Waterline will collect water samples from other identified domestic water sources, such as springs, creeks, or storage tanks during the baseline testing program. Where feasible, Waterline will also collect water quantity data for these sources, such as flow rates or tank size. Water samples will also be collected from surface waterbodies, such as creeks, rivers or lakes, that are located near domestic water supply wells to classify chemical types and identify any potential surface water-groundwater interaction.
The baseline testing results are used to:
Identify any existing water supply integrity issues with respect to quality or quantity;
Make recommendations to the community regarding water supply system maintenance or treatment; and
Provide a benchmark to which future changes in water supply quality or quantity can be assessed.
Data management and ongoing testing and maintenance are essential for ensuring the water supply integrity into the future. Details regarding ongoing testing, maintenance and data management programs are presented in a separate video.
For more information on how Waterline can help, please contact our water source integrity program coordinator Brent Morin at firstname.lastname@example.org.