Observation Well Information

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Introduction

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 %

Summerland observation well graph

Hydrograph Analysis- Observation Well No.158

The hydrograph above shows the change in ground water level in the observation well (meters below ground level) over time. This observation well is manually monitored each month using a wetted tape.

Observation well No.158 is completed to a depth of 15.2 m in aquifer number 0297, a confined, sand and gravel aquifer. The aquifer is classified as an IIIB (11) aquifer, which is lightly developed and moderately vulnerable to contamination. Since 1969, the ground water level in the well has ranged from a high of 1.4 m below ground level in June 1972, to a low of 14.4 m below ground level in December 2001. The difference between maximum and minimum ground water levels in any single year ranges from approximately 0.5 (in 1992) to 9.0 (in 1972) meters. The hydrograph shows that ground water levels in this observation well generally follow a regular pattern. Maximum ground water levels occur in June, July and August, and minimum ground water levels occur in the months of April and May. The water level in this observation well may be affected by nearby irrigation causing pumping interference and recharge by irrigation return flow to the aquifer. Since 1973, this well has generally shown a slightly declining trend in ground water levels.

NOTE* Detailed water level information for this well is available in Excel Format.
For more information, please email
groundwater@gov.bc.ca