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Keep it Clear

Protect your water—it’s just beneath your feet.

Pollutants that go down the storm drains could end up in your water. These contaminants also have the potential to harm local wildlife in nearby waterways.   

Watch the video and click each culprit below to learn about common pollution issues and how you can prevent further impact to our groundwater.

Learn About Common Pollution Culprits

Trash & Litter

The number one pollutant in our stormwater collection system, litter causes many problems for our groundwater. It can clog the basins, which reduces the infiltration and replenishment of rainwater into the groundwater. The solution is simple: don’t litter!

How can I help?

Properly dispose of your trash by following city guidelines regarding cans and pick-up days. You can also volunteer to clean trash. Learn more on our informational website. You can also learn about Clean-Up schedules in Fresno, in Clovis, and in the County.

Motor Oil

Motor oil is one of the hardest contaminants to remove from our water, so it should never be dumped down storm drains. When you change the oil in your car, runoff can go into the gutter and enter the stormwater collection system.

How can I help?

When you change your car oil, or perform other maintenance, properly dispose of the motor oil at a designated collection site. To learn more, visit the Fresno County website for information about used oil and other household wastes.

Paint & Paint Thinner

Paints and paint thinners become serious offenders of groundwater pollution when they are dumped on the ground or into storm drains. When cleaning after a home renovation project, toxins can enter the stormwater collection system and pollute the water supply.

How can I help?

When you are finished with your paint and paint thinner, make sure you properly dispose of it at a drop-off site.

Pool Draining

Most pools do not need to be drained often. But even regular maintenance, such as cleaning the filter, can cause pollution to enter the storm drains if not done properly. When pool water is drained into or near a storm drain, chlorine and other chemicals can enter the groundwater.

How can I help?

If draining your pool, contact first the city, then the district, with the address of the pool, the amount that will be discharged, and the planned date for drainage. If you live in Clovis, visit their Public Utilities website for more information. If you live in Fresno, visit their Public Utilities website. Then contact the district via phone at (559) 456-3292.


Before dumping sewage, which includes RV waste, wastewater, commercial kitchen oil, or any cleaning solution, you have to find the right place to do so! Sewage is harmful to the environment and should never go down the storm drain because it can contaminate our groundwater.

How can I help?

Always make sure to empty your sewage waste in a designated dump station. Find more helpful tips about sewage maintenance at the Fresno Public Utilities website.

Fertilizer & Pesticides

If you fertilize or use pesticides in your yard, you may be polluting the groundwater. Inadvertent overwatering leads to chemical contaminants flowing into the storm drains. Nitrates from fertilizers and toxins from pesticides are soluble pollutants that can quickly reach our groundwater.

How can I help?

Start by figuring out when and how much you need to water your yard. Visit the fertilizer and pesticides information page for details about water schedules and smart gardening. For questions about eco-friendly and less-toxic alternatives, integrated pest management, and proper chemical disposal, contact your local Master Gardener.

Ask An Expert


Eco-Friendly Pest Control

Learn how to solve pest problems with less-toxic products—keeping your children, pets, and garden healthy!

Household Hazardous Waste Information

Learn more about what waste items can be hazardous to your health and how to safely dispose of them.

10 'Most Wanted' Bugs in Your Garden

Learn more about these beneficial bugs and how they keep problem pests under control naturally, without the use of harmful chemicals.

Ask an Expert

Learn more about the 153 flood basins managed by the District, wildlife in the area, and our unique stormwater system in our Ask An Expert video series.

FREE Activity Book & School Curriculum

Learn more about how stormwater run-off and pollution affect the community with fun activities and useful classroom materials!