Observation well WSA Nokomis was constructed in 1966 to a depth of 99.67 metres to monitor natural groundwater level fluctuations in the Hatfield Valley aquifer system. In 2008, a replacement well was completed to a depth of 99.97 metres. The wells were completed into medium to coarse grained sand of the upper portion of the Empress Group within the Hatfield Valley Aquifer. The Hatfield Valley was cut into bedrock during the first glacial advance. In the area of the observation well, the longitudinal groundwater flow is directed toward Last Mountain Lake and the Qu'Appelle Valley. The aquifer is recharged by lateral inflow from the Wynyard Aquifer but may also receive direct recharge from precipitation. WSA Nokomis is under flowing artesian conditions with a head of approximately 2 metres above ground level.
The Saskatchewan Research Council concluded that the well was influenced by an irrigation well about 11 kilometres to the north, but the details of this well are unknown. Seasonal fluctuations for the well range from less than 0.1 up to 0.6 metres. The hydrographs's record low of about 514.2 metres occurred in 1985 while the record high of about 515.6 metres occurred in 2011. Water levels have remained very high.
The well yields water of the sodium/bicarbonate-sulphate type and it has a Total Dissolved Solids concentration of about 2620 mg/L.