Water Quality Management
Many different factors can influence the quality of the water in your tank. Whether it’s fluctuating pH levels, changing temperatures, disinfectants reacting with organic materials, or water that has aged, the end result can be devastating. It may cause complaints from the public and negative PR, fines from governing bodies, or most importantly, health and safety risks.
Avoid all that and get compliant by proactively managing the quality of your water.
How is Water Quality Monitored?
Standards are set by the EPA and enforced by the state health department or division of water supply. Once per quarter, the state examines their hydraulic map and your distribution system and tells you when to pull a sample for them to test. This sample is sent to an independent lab, which gives a reading on total trihalomethane (THMs). If your sample measures over 0.8 ppm, you are required by law to send out a notice to the public. Furthermore, the governing agencies are beginning to enforce fines that are pro-rated depending on the size of your customers’ base—these are sometimes in the six figures.
To manage the quality of your water, we:
- Conduct internal inspections using ROV: An HD Remotely Operated Video system
- Determine the conditions needed to address water quality
- Conduct temperature/stratification testing
Check out the GridBee and SolarBee product guide to help ensure the highest water quality of your tank.
The temperature in tanks is one of the most common issues with managing the quality of water.
Thermal stratification can lead to lower quality water through the loss of disinfectant residual and accelerated nitrification, which leads to the formation of THMs. It is caused by insufficient mixing of the water in your tank. Even if you turnover your water frequently, your water is still at risk of thermal stratification due to differences in water and ambient temperature and even thermal radiation.
What Happens? Thermal Stratification Explained
As your tank is warmed by the sun, the warmer water rises to the top of the tank and the cooler water — which is denser — ends up at the bottom. This creates a thermal barrier between the warm and cold water in the tank known as a “thermocline” — and it prevents the tank from mixing. This can persist for days as your tank is drained and refilled. The older, warmer water remains trapped inside and gradually produces disinfection by-products (DBPs). By the time that water leaves your tank, it is most likely not optimal quality.
Tank Mixing: 24/7 Protection from Stratification
The solution to stratification is tan mixing, which circulates the water in your tank 24 hours a day, seven days a week, 365 days a year. All the water stays at the same temperature, meaning a thermocline never forms. This preserves the integrity of your water quality.
A tank mixer:
- Blends old and new water
- Creates uniformity of disinfectants
- Reduces temperature variances
- Prevents ice formation
Turnover plays a vital part in the health of your tank and the quality of the water. In essence, turnover (paired with mixing) defines the average age of the water in your tank. The faster it turns over, the fresher the water in your tank.
Optimizing turnover can help to reduce or eliminate:
- Temperature stratification
- Loss of disinfectant residual
- Build up of disinfection by-product (DBP) spikes
- Bacteria regrowth
- Biofilm growth
- Unpleasant taste and odor
How Much Turnover Does Your Water Need?
The right level of volume turnover varies, depending on elements such as the source of your water, the treatment process it undergoes, and the condition of your tank. In an ideal world, you would change out approximately 50% of your water every 48 hours. But this isn’t always possible.
However, turnover alone isn’t a perfect solution — without mixing the water, you could bring stratified water into the system and leaving older water in the tank for far too long.
Sediment and microbial growth can lead to nitrification and the formation of trihalomethane (THM) in your tank. Sediment can be removed with the tank in or out of service. It may be necessary to drain and clean the tank, scrub all internal surfaces, disinfect the tank (and any pumps, hoses etc.) with a concentrated chlorine solution and then thoroughly flush the tank. The last thing you want is a complaint from a customer, a fine, or worst of all, a health scare. We can perform all the necessary steps to clean and treat your tank so that the water quality remains in compliance with national standards.
Depending on your system, we may be able to reduce THMs by mixing the tank and recirculating the water only. It may necessary to go to the next level of installing an actual THM removal system at the tank.
Check out this case study to see how we helped one of our customers with their tank’s water quality.