Water clarity is a major issue for many pools, especially seasonal, outdoor facilities, where staff may not be trained or experienced with pool operations, and there may be no dedicated maintenance staff. Pool operations, whether performed by the lifeguards, or other staff, is an important duty - when properly done, water quality ensures the safety and comfort of patrons, and makes lifeguarding easier. NLS-trained guards know that scanning cloudy water is impossible, and patron complaints about chemistry imbalances are a headache best avoided. Here are some tips to keep your water clear and the chemistry balanced.
Keep your filtration system running at optimal levels. For sand or sand/gravel filters, regularly backwashing the filter will ensure maximum efficiency, and helps keep the required amount of chemicals low. For diatomaceous earth or cartridge systems, the medium must be cleaned or replaced. These systems vary greatly, so contact the manufacturer.
Chlorine levels should remain as stable as possible over the length of the day - regular chemistry tests and record-keeping will assist you. Automatic chlorine pumps are ideal, and are more efficient (and safer) than manually adding chemicals. Free available chlorine (the chlorine available to do the work of sanitizing the water) should remain within the 0.8-1.5ppm. Free available bromine should be maintained at 2ppm. Outdoor pools should take care to use stabilized chlorine or to add a stabilizer. Chlorine will break down in sunlight unless this is done, and you will use far more chlorine than otherwise necessary to maintain adequate levels. If adding stabilizer (cyanuric acid, "dichlor" or "trichlor") maintain a level of 15-30ppm (ideal is 20ppm) - a special test is done to determine the concentration, and should be provided with a standard test kit. Levels can be reduced only by diluting the stabilizer - drain some pool water and refill with fresh water.
Ideal pH for water in swimming pools is between 7.2 and 7.8 - outside that range, swimmers will complain of irritation, and other chemicals in your water will function less effectively. High pH can cause discolouration of the water and gritty, itchy eye irritation. Low pH can cause corrosion of pipes and metal fittings, discolouration of dyed hair, and stinging eye irritation. If pH is too high, add an acid - this is normally muriatic (hydrochloric) acid. If pH is too low, add a base or alkaline such as soda ash (sodium carbonate). Extra training is required to handle these chemicals safely, and to calculate the proper amounts to add. Take care not to overreact. The pool water is a buffer, and will change pH quickly within it's buffer zone - small additions of acid or base will make big changes to pH.
While Nova Scotia currently does not have a regulation on water clarity, a good guideline is to place a black circle 12cm in diameter on a white or light background at the deepest point of your pool. The black disc should be visible from any point on the pool deck within 9m. If the water is not clear enough to clearly see the disc, the pool must be closed immediately. On duty lifeguards do not need the permission of anyone to close the pool if they feel the facility is unsafe. Do not wait until water clarity is extremely low to begin treatment. Adding a clarifier or flocculant to the water stream before it reaches the filter may be helpful, and provides an extra bit of protection against Cryptosporidium. However backwashing is the best solution to low water clarity.