WSA Pierce No. 1, No. 2, No. 3
Due to concerns in Saskatchewan that groundwater withdrawals occurring in Alberta could impact groundwater supplies in the Cold Lake/Waterhen area, three observation wells were installed in 1992 on the Saskatchewan side of the border west of Pierce Lake. These wells are WSA Pierce No. 1 which was completed to a depth of 111.56 metres into Empress Group sediments of the Hatfield Valley aquifer, WSA Pierce No. 2 was completed to a depth of 71.32 metres into intertill sands and WSA Pierce No. 3 which is completed into shallower intertill sands at a depth of 19.8 metres.
In Pierce 1 the lowest recorded water level of about 507.5 metres occurred during the first year the well was monitored. Following that water levels increased until 1997 when the historic high of about 508.4 metres occurred. Since that time water levels have fluctuated at around 508 metres.
Water levels in Pierce 2 began to rise the year after its completion, reaching the hydrograph’s maximum water level of 526.5 metres in 1997. The well’s minimum water level of about 525.75 metres occurred in early 2004. Following that, water levels have been on an increasing trend and are currently around 526.3 metres.
In Pierce 3, the record high water level of about 516.7 metres occurred in 1998 and 1999 while the record low of about 516 metres occurred in 2005. Following this, water levels have been on an increasing trend and are at their highest levels since 2000.
The water level in Pierce 2 is about 18 metres higher than in Pierce 1 and about 10 metres higher than in Pierce 3. This suggests dicharge occurs from the deep intertill aquifer down into the Hatfield Valley aquifer and also upwards into the shallower intertill aquifer in which Pierce 3 is completed. Flow in the Hatfield Valley aquifer in the area of the well site is likely eastward while the flow directions in the two intertill aquifers are unknown.
The sum of ions concentration in Pierce 1 is about 1370 mg/L and is of the sodium-bicarbonate/chloride type. The sum of ions in Pierce 2 is about 1270 mg/L and is of the calcium-bicarbonate/sulphate type. No water quality information is available for Pierce 3.