What you need to know about the North Texas Municipal Water District, your water and your rates

Welcome to the North Texas suburbs, where there’s a good chance you, your neighbors and residents of the next town over get their water from the North Texas Municipal Water District.

Here are four questions and answers to help you understand how the district provides your water and sets your rates.

The district is a water utility company that sells treated water to 80 cities and towns from Denton to Kaufman counties. It was officially created in 1950 because of a diminishing supply of groundwater in the region, according to the district.

The 10 original cities were Farmersville, Forney, Garland, McKinney, Mesquite, Princeton, Plano, Rockwall, Royse City and Wylie. Richardson joined in 1973, Allen in 1998 and Frisco in 2001.

How are water rates determined?

The 13 member cities have lower water rates because they are financially responsible for the debt that pays for the district’s infrastructure projects.

This year, the rate for a member city is $2.99 per 1,000 gallons delivered, and $3.04 for a customer city. The dozens of customer cities include Sachse, Rowlett, Sunnyvale, Murphy, Little Elm and Prosper.

Rate adjustments, which have happened every year since 2006, occur because of maintenance and costs associated with projects such as the Wylie Water Treatment Plant and Bois d’Arc Lake, according to the district. The new reservoir in Fannin County is closer to opening after heavy rainfall in the spring and is expected to begin delivering water in 2022.

The charges cover acquiring, storing, transporting, treating, testing and delivering the water to providers who pipe it to North Texas homes and businesses.

Cities then establish their own water rates in tiers based on water usage. The less water people use, the lower their rates.

Why was there a lawsuit over rates, and what happened?

Water rates were at the center of a long-running dispute between the 13 member cities and the district related to the cost-sharing “take or pay” methodology that member cities first agreed to back in 1953.

Plano, Richardson, Garland and Mesquite argued for almost 20 years that the rate structure was outdated because — especially as a result of conservation — they no longer needed nearly as much water as they were contractually obligated to buy.

Last October, the district and cities unanimously agreed to a new wholesale rate structure that will determine each city’s share of costs. Over the next seven years, the  annual minimum each city had committed to pay will gradually adjust to align overall costs with the city’s actual historical consumption.

How much these wholesale-cost changes affect suburban water bills will vary, depending on the retail customer rates that each city sets.

Where does the water come from and how is it treated?

The district was responsible for the construction of Lavon Lake near Wylie, the largest water source for North Texas.

Its water also comes from Jim Chapman Lake east of Greenville, Lake Texoma near Denison, Lake Tawakoni south of Greenville and the East Fork Water Reuse Project, a large man-made wetland that naturally filters water from the Trinity River.

This water is treated at one of six plants operated by the water company. The treatment first uses a process to drop large particles, such as dirt, to the bottom of the water. It is then disinfected to destroy any remaining parasites, bacteria or viruses and tested before being piped to water towers and eventually your sink.

For one month every spring, the water in member cities might taste like chlorine while the district changes the disinfectant in its water treatment process.