07 Jul Bore/Well Water
Unlike municipal water which is subject to regular testing, very few regulations exist to govern private well and bore water supplies. The onus therefore falls on the owner to check the pH and conduct regular testing for microorganisms, pesticides and nitrates.
There are several concerns associated with obtaining your drinking water from a bore or well that warrant mentioning.
- Ground water quality varies from place to place depending on its geographical location. This will determine the presence or absence of natural impurities such as nutrients from rocks and soil, heavy metals, radon gas, boron and selenium and proximity to farming and other industries. In some parts of Australia, concentrations of naturally occurring elements such as arsenic, fluoride and uranium, or nitrates from agricultural land uses, may exceed safe levels (National Health and Medical Research Council, 2004).
- Radioactive minerals such as uranium maybe found naturally within the ground. Uranium breaks down into several isotopes one of which is radon gas which may cause lung cancer when inhaled. A recent preliminary survey of the radioactive content of Australian drinking water found that ground water contains higher levels of radioactivity when compared with surface water and that these levels were considerably higher than the world wide average (Long et al, 2008).
- Nitrates and nitrites found in fertilisers (from agricultural run off), animal wastes, septic tanks and sewage treatment systems are a common problem with ground water. High levels of nitrates may lead to blue baby syndrome (methemoglobulinemia).
- High salt levels can be a problem with ground water which may make it undrinkable.
- Pesticide drift is a very real threat in farming communities and timber plantations (that spray prior to felling) which makes regular testing vital to account for accidents and seasonal variations.
- Micro-organisms may occur as a result of seepage from septic tanks or manure from livestock and domestic animals or from storm water contamination. Micro-organisms are generally more of a problem during drought conditions as a result of shallow water or they can be introduced into the well from flooding.
- Heavy metals such as lead and copper may occur as a result of corroding domestic pipe or heavy metals could be generated from nearby industry such as mining, metal smelting, timber milling or building construction.