Create an Account - Increase your productivity, customize your experience, and engage in information you care about.
The hardness of the water is normally between 25 to 35 milligrams per liter (mg/l ) or parts per million (ppm). Various levels of hardness in terms of calcium carbonate can be described as follows:
Note: Most manufacturers of dishwashers maintain that after about 120 mg/l of hardness that some means of softening or removal of hardness should be used to ensure no spotting of the dishes.
Show All Answers
We perform many tests of the water to ensure that it meets all of the State and Federal standards. These tests are performed hourly, daily, weekly, monthly and yearly from the source waters, the in-plant water and throughout the distribution system. If you have any questions or concerns, please call Public Works at 208-746-1316.
A brownish tint in your water could be caused by several things but is normally attributed to iron in the water. This normally comes from the piping within the building as from old galvanized lines.
A white or milky color in the water would normally be caused by a release of oxygen in the water after it is drawn from the faucet. To determine this, draw a glass of water and let it sit for a few minutes. Watch to see if the color slowly disappears from the bottom to the top.
Should you have any problems associated with color, please call Public Works at 208-746-1316. We will be glad to investigate any problem and attempt to determine a solution.
The water distribution system has various pressure zones. Your water pressure will normally vary only slightly within each zone. If you are seeing a drop or increase in your water pressure, there could be a problem in your building. Most buildings are required to have a pressure-reducing valve installed. These valves maintain a set pressure and when they fail can cause either an increase or a decrease in pressure. Call Public Works at 208-746-0593 to assist in determining your problem.
For more helpful information on water savings visit the WaterSense website.
About 85% of the potable water in the Lewiston system comes from the Clearwater River. It is then treated in a conventional water treatment plant. This consists of clarifying the raw or river water by adding chemicals that coagulate the impurities and then these are settled in a basin. Finally, the water is passed through a mixed media filter. Sodium Hypochlorite is added for disinfection and to maintain a residual in the distribution system.
Fluoride is added to the water as an aid to dental decay. The pH is adjusted to be more neutral to prevent mineral depletion from the piping.
The remainder of our water comes from wells. Lewiston has six wells. Three are used primarily for irrigation of parks, the cemetery, and a golf course. Three are utilized for domestic needs.
The average daily production annually is 4.1 million gallons per day (mgd). This may peak in the summer months to about 7.5 to 8.5 mgd. The average flow in the winter months is about 1.5 mgd.
Our system contains six reservoirs and two clear wells that have a capacity of about fifteen million gallons. This is in reserve on a continual basis for domestic, commercial and fire flow use as each day the reservoirs are filled.
Yes. The City will perform testing of customers’ water for identified problems or concerns. We have a routine testing program in the distribution system to test for bacteria and chlorine residuals. Daily testing is performed for a variety of other parameters. Other chemical testing is performed quarterly and annually. (See the annual "Water Quality Report").