Many of us in rural communities rely on ground water for drinking, domestic, agricultural and industrial uses. Our streams, fish, and wildlife also depend on ground water.
Ground water comes from snow, rain, sleet, and hail that soaks into the ground. Ground water is all the water below the ground surface. The water moves down into the ground because of gravity, passing between particles of soil, sand, gravel and rock until it reaches it reaches a depth where the ground is filled, or saturated with water (think of a big sponge). The area filled with water is called the saturated zone and the top of this zone is called the watertable.
The water in lakes, rivers or oceans is called surface water. Ground water and surface water can trade places and intermingle. In dry months streams rely on ground water to sustain flows.
In some rural areas ground water is the only source of drinking water. In B.C., over 25% of water used is ground water. Ground water is an important resource that can be easily contaminated.
Contamination can be point source or non-point source ( distributed) so hiding source of contamination can be at times difficult.
Potential sources of point source contamination are:
- On-site septic systems
- Leaky tanks or pipelines containing petroleum products
- Leaks or spills of industrial chemicals at manufacturing facilities
- Underground injection wells (industrial waste)
- Municipal landfills
- Livestock wastes
- Leaky sewer lines
- Chemicals used at wood preservation facilities
- Mill tailings in mining areas
- Fly ash from coal-fired power plants
- Sludge disposal areas at petroleum refineries
- Land spreading of sewage or sewage sludge
- Road salt storage areas
- Wells for disposal of liquid wastes
- Runoff of salt and other chemicals from roads and highways
- Spills related to highway or railway accidents
- Coal tar at old coal gasification sites
- Asphalt production and equipment cleaning sites
Potential sources of non- point source contamination are:
- Fertilizers on agricultural land
- Pesticides on agricultural land and forests
- Contaminants in rain, snow, and dry atmospheric fallout
In B.C. numerous ground water resource conflicts currently exist in various parts of the province such as:
- well interference where large capacity wells lower water levels and yields of neighbouring wells, (e.g. Surrey, Mill Bay, Saanich);
- artesian wells which are allowed to flow freely thereby wasting water and lowering water levels and yields in neighbouring wells, (e.g. Surrey, Okanagan, Gulf Islands, Saanich);
- ground water-surface water conflicts, particularly where surface water is fully licensed and ground water extraction depletes surface flows and availability, (e.g. Cherry Creek / Kamloops, Chimney Creek / Williams Lake, Kalamalka Lake);
- excessive ground water withdrawals in coastal areas resulting in salt water intrusion and quality degradation, (e.g. Gulf Islands, Saanich);
- poor well construction practices which result in degradation of ground water quality and contamination, (e.g. Gulf Islands, Saanich);
- health risks, public safety and environmental hazards associated with uncapped and abandoned wells, (e.g. Lower Mainland and Okanagan Valley).
The Ground Water Protection Regulation was created in 2005 to improve the safety and quality of B.C. ground water resources. The regulation requires that all water wells be properly constructed, maintained, and at the end of their service, properly deactivated and closed. All new drilled wells and dug water supply wells must have a surface seal, secure well cap and well casing stick-up, and the wellhead must be graded so surface water drains away from wellhead, and the well must have an identification plate , and the well must be constructed that stops or controls any artesian flows.
Tips to avoid groundwater conflicts or contamination:
- Don’t apply pesticides or fertilizers near a well
- Don’t use toxic chemicals on your driveway
- Don’t pile garbage or manure within 100m of a well
- Check fuel storage tanks for leaks regularly
- Don’t flush chemicals, paint or oil down toilets. Please recycle all of these products in a responsible way.
- Use non-toxic products for cleaning. Read the labels and learn what is environmentally friendly
Ground water is a resource we must protect for the future.