Water Plant Manager’s Spring Update

Water restrictions for the 2011 irrigation season will be on a voluntary basis. You are encouraged to follow the same restrictions that have been in place past years:

• Even and odd day watering according to the address of your property

• No watering between 10:00am and 4:00pm.

Should you choose not to follow voluntary water restrictions there will be no enforcement or penalty.

Keep in mind if you water during the heat of the day, you will loose up to 50% of the water you apply to evaporation. This is reasoning behind not watering between 10:00am and 4.00pm. The even, odd day system has half the city water one day, half the next. This provides better water pressure for all customers and fire fighting capabilities.

This year is a trial period for voluntary water restrictions. Should demands become too great for the treatment plant or we receive an increased number of low water pressure complaints, then water restrictions could again become mandatory and enforceable.

I would also like to take this opportunity to talk about routine bacteria sampling that occurs within the water distribution system. We are required, based on population to take seven bacteria samples per month. The samples are taken at sites predetermined by a sampling plan. The plan contains twenty one routine sampling sites with seven alternate sites. If for some reason the routine site is not accessible then an alternate site is used. The sampling each month is spread through out the system rather than being concentrated in a certain area. Each site by years end will have been tested four different times.

The water distribution system contains many miles of piping to get the treated water to our customers. Chlorine residual is maintained throughout the distribution system to assure a level of water quality. Chlorine levels are tested every time a bacteria sample is collected. Chlorine levels are also measured at every treatment point daily and at the surface water plant continuously. A predetermined site within the distribution system is also tested daily.

Another important aspect to good water quality is maintenance of the distribution or piping system. The key element is a good flushing program. This part of system maintenance is often mistaken by the public as a waste of water. Flushing rids the system of accumulated sediment and discolored water. Flushing also gets rid of old water, or water that’s been in the system for periods longer than normal. This can occur in areas with lower usage or dead end lines. Getting old water out of the system reduces the potential associated with the formation of disinfection by products.

The city is currently flushing hydrants twice per year. The spring flush has already taken place and the second flush will occur in early October. Based on data reordered during flushing in past years, less water is being used to flush twice per year than was used when hydrants were flushed annually.

Two major projects, both associated with the Gallery Water Tank, have been completed. The first project was the installation of a new roof on the tank. A new single ply roofing system was installed along with some minor exterior concrete work. A new access hatch and one additional vent were also installed as part of the project. The new hatch required a larger opening to accommodate easier material handling for interior repairs.

The second project completed early this spring was installation of an interior liner to the existing concrete storage tank. The tank was experiencing increased leakage of treated water. Some attempts were made in the past to seal the tank by patching suspect areas. This helped to slow the leakage but never stopped water loss completely.

The best and most cost effective fix after looking at several options was the polypropylene geomembrane.The membrane was mechanically attached to the existing concrete walls of the tank above the high water level. All seams on walls and floor were heat welded and tested for quality. All support columns and concrete piers were also lined to completely seal tank interior.

Completed and back in service, the tank shows no evidence of leakage in areas that were visible before.