Diablo Water District

We are pleased to present the 2017 Annual Water Quality Report highlighting the exceptional quality of your tap water. This report not only showcases the safety and reliability of your water supply, but also provides valuable insights about where your water comes from and the sophisticated infrastructure required to deliver it to your home or business.

As water providers to more than 500,000 residents, we take tremendous pride in delivering water that consistently exceeded all state and federal municipal water standards throughout 2017. For comprehensive test results, please refer to pages 7-11.

This report includes water quality data collected during 2017 and addresses common questions about your tap water. You can trust that your water meets high quality standards, as regular testing and continuous improvements to our treatment processes ensure your drinking water remains among the nation's finest.

We hope you find this information valuable in understanding the quality of your water service. If you have questions about tap water in your neighborhood, please contact your water provider using the information listed on the left.

1. What is stormwater runoff?

   Stormwater runoff occurs when rainfall flows across land surfaces instead of seeping into the ground. This water typically flows untreated into the nearest stream, creek, river, or lake, carrying various pollutants it collects along the way.

2. Who regulates stormwater runoff?

   The United States Environmental Protection Agency (EPA) regulates stormwater through the National Pollutant Discharge Elimination System (NPDES). In Texas, the EPA has authorized the Texas Commission on Environmental Quality (TCEQ) to implement this program, making them responsible for permits and enforcement activities statewide.

   McKinney participates in the Phase II MS4 program, requiring the city to develop a comprehensive stormwater management program to eliminate illicit discharges and reduce pollutants in runoff.

3. Why is stormwater management important?

   Runoff occurs with every rainfall. When stormwater enters storm sewers, it can carry pollutants like petroleum products, pesticides, detergents, and harmful chemicals that damage aquatic ecosystems and harm fish, shellfish, and plant life.

4. How does stormwater pollution affect me if I don't live near streams?

   Local streams feed into larger rivers, lakes, and eventually oceans. If you enjoy swimming, boating, or fishing in these waters, you're affected by water quality. Polluted waterways may be closed for recreation due to health concerns. For creek-side residents, sediment and debris can cause property-damaging floods. Additionally, since creeks discharge into drinking water sources, pollutants require more treatment, potentially increasing water bills.

5. Where does McKinney's stormwater discharge?

   Depending on your watershed location, stormwater from McKinney's Municipal Separate Storm Sewer System (MS4) flows into either Lake Ray Hubbard or Lake Lavon.

Storm drain markers in your neighborhood serve as reminders that materials entering these drains eventually reach our lakes. If your area's drains aren't marked, please contact Stormwater Management at 972-547-7579.

For more information about stormwater management standards, visit the Stormwater page. The City of McKinney assesses a Stormwater Utility Fee to help maintain the system - contact Water Billing at 972-547-7550 for details about this charge.

The Public Works department (972-547-7350) maintains storm drains. Please report any clogged inlets in your neighborhood.

Yard waste shouldn't enter storm drains because when organic materials decompose in waterways, they consume oxygen needed by aquatic life. While natural systems can handle limited organic inputs, urban areas can overwhelm streams with debris, depleting oxygen and potentially causing flooding by clogging inlets. Remember: storm drains are for rainwater only.