Observation Well Information

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The Province operates a network of observation wells to provide data on ground water level fluctuations and ground water quality information on developed aquifers in British Columbia. Observation well water levels are monitored using one of four methods: 1) manually with a wetted tape, 2) continuously using Steven's chart recorders, 3) electronically with data loggers or 4) remote monitoring using cellphone technology.

Water level data from observation wells are collected on a monthly basis by field observers and forwarded to Regional Offices. Data are then checked for errors and ommissions and forwarded to the Water and Air Monitoring and Reporting Section for final checking and storage. Water level data are referenced from ground level and the month end water level reading are entered and stored in Excel to produce a month-end hydrograph. The method of measurement and accuracy of each method are given below:

Method of measurement Accuracy
Wetted Tape Method +/- 1 mm
Steven's Chart Recorder +/- 1 mm
Data Logger +/- 0.1 %

Glidden Rd Central Saanich observation well

Hydrograph Analysis- Observation Well 061

The hydrograph above shows the change in ground water level in the observation well (m below ground level) over time.

Observation well 061 is completed in an unmapped, sand and gravel aquifer to a depth of 27.4 m. Since 1970, the ground water level in the well has ranged from a high of 6.6 m below ground level in May 1998, to a low of 9.4 m below ground level in July 1975. In the period from 1974 to 1980, there is a possibility that ground water levels were affected by the pumping interference of a production well nearby. In 1980, the hydrograph begins to show ground water levels that are generally following a more regular seasonal pattern. Maximum ground water levels occur yearly during March, April and May corresponding to ground water recharge from seasonal precipitation, and minimum ground water levels occurring in August, September and October. The difference between maximum and minimum ground water levels in any single year ranges from approximately 0.3 to 2.3 metres.


NOTE* Detailed water level information for this well is available in Excel Format.
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