Homepage > Residents > Water > Stormwater


Big Dry Creek Streambank Restoration Project

photo credit

Big Dry Creek runs through a clean meadow.

Photo by

Keep It Clean, We're All Downstream

photo credit

Sunset at Lake Standley.

Photo by

Protecting People, Property, and Our Environment

The City of Westminster manages two stormwater basins:  

  1. Big Dry Creek: Precipitation north of 92nd Avenue flows to Big Dry Creek 
  2. Little Dry Creek: Precipitation south of 92nd Avenue flows to Little Dry Creek 

Westminster partners with the Mile High Flood District area for mitigation and maintenance projects throughout the area. 

Stormwater is the collective term used for precipitation once it hits the ground. Stormwater includes rain, hail or snow that is either absorbed into the ground, captured in a retention pond or flows into waterways. Although rain and snow is always welcome in our semi-arid climate, stormwater can become an environmental problem when it lands on our city’s non-absorbent surfaces, such as roads, sidewalks and parking lots. That’s because the runoff sends dirt, debris, oil and other pollutants into our creeks and rivers. Unlike sanitary sewers that go to a treatment plant, stormwater is not treated before discharging into the environment. 

How You Can Help Keep Our Waterways Clean 

Ways you can help us reduce stormwater pollution:  

  • Clean up after yourself and your pets to prevent unnecessary products and pollutants from going down the storm drains. Learn more here. 
  • Attend one of the stream cleanup events the City hosts throughout the year. See what’s scheduled on the City Events calendar.  
  • Attend a meeting for or learn more about the Environmental Advisory Board. 
  • Adopt a street to clean up trash and other pollutants that end up in our waterways. 
  • Be on the lookout for opportunities to contribute to and create storm drain art.  


Limit Salt And Ice Melt Use In Winter 

As snow and ice melts, it carries excess salt and other chemicals into our waterways, which can harm the environment Please consider using waterway-safe salt alternatives or minimizing use of salt or ice melt by clearing the area of snow and ice before applying ice melt products. 



Big Dry Creek Streambank Restoration Project 

The City of Westminster is partnering with the Mile High Flood District to improve Big Dry Creek’s water quality and flood management capabilities. These efforts should make Big Dry Creek more resilient to intense storm runoff events. Together, we are repairing and stabilizing Big Dry Creek’s streambanks from 112th Avenue to Wadsworth Boulevard.


Frequently Asked Questions

Sign up for emergency alerts via text, email, or voicemail with LookoutAlert.  
City of Westminster single-family water bills include a $6 charge per water meter. This fee covers the entire range of services including maintenance, construction of storm water infrastructure as well as environmental compliance, flood control, facility inspections, and overseeing construction sites. This fee also pays for the City’s free Hazardous Household Waste Program and street sweeping program.   


The sanitary sewer system collects wastewater from homes, businesses, and other buildings in sanitary sewer lines. It then flows to water reclamation facilities where the water is treated and released back into the environment. 
The storm sewer, on the other hand, collects runoff from storms or irrigation, which then drains directly to our creeks, rivers, and lakes without treatment. 

Storm vs. Sanitary.jpg

Storm drains are connected directly to our water ways, including Big Dry Creek, Little Dry Creek, and Standley Lake. 

When this water washes over yards and streets, it collects fertilizers, pesticides, oil, pet waste, and other pollutants. These pollutants then release excess nutrients into the environment, creating the perfect condition for excess algae growth.  

Too much algae does more than just make fishing and swimming unpleasant—It can severely hurt our water quality As algae decay, they use up oxygen in the water that fish and other wildlife need to survive. This decaying not only potentially hurts the water’s ecosystem, it could also make humans and pets sick.  


It’s illegal to discharge swimming pool water into public space. Chlorinated swimming pool water may also not be discharged into the storm drain or ditches. Storm drains and ditches convey water directly to rivers and streams, and chlorinated water can kill aquatic life. The penalty is up to $1,000. Please select one of the following two options below for discharging swimming pool water properly. For guidance on draining saltwater pools, please call the Stormwater Hotline at 303-706-3367stormwaterhotline@westminsterco.gov.

Option 1: Drain to a vegetated area on your property

Drain dechlorinated water to the grass/turf/or any area on your property that will allow the water to absorb into the ground, if and only if...

  • You do not cause flooding of your neighbor’s property or any other adjacent property.
  • The land area is sufficient to prevent erosion and runoff into a ditch, creek, or other conveyance (i.e. storm drain).
  • You do not cause harm to the environment. This water can be used to irrigate plants, saturate dry ground, or soak into mulched areas.
  • Pool water may not be discharged into unpaved roads and alleys.

Option 2: Dechlorinate pool water before discharging into a storm drain

Dechlorinate the pool water before draining it into the storm drain. Consider the following options for removing chlorine:

  • Simply stop adding chlorine to your uncovered pool and wait. Sunlight will help to naturally dissipate the chlorine within 10 days.
  • Chemically dechlorinate the pool water. Chemicals that will quickly remove chlorine are available through pool and spa care vendors. Follow the directions on the product label.
  • Verify water is dechlorinated with a pool testing kit (<(less than) 0.1 mg/L).
  • Pools may not be permanently connected to a storm drain or drainage channel.
  • NEVER discharge filter backwash to the storm sewer system.

Pool water may be discharged to the storm drain only after all of the following conditions are met:

  • Other disposal methods (i.e. landscaping) are not possible.
  • The pool or spa is completely dechlorinated.
  • The pH of the water is between 6 and 9.
  • There is no discharge of filter media.
  • There is no discharge of acid cleaning wastes.
  • Discharge water will not pond or flow to neighboring properties.

If you have any questions or want additional guidance, please email or call the Stormwater Hotline at stormwaterhotline@westminsterco.gov or  303-706-3367. If you see someone draining a pool into the street and you smell chlorine in the water, please report this to the Stormwater Hotline.


Contact our stormwater hotline at 303-706-3367 or stormwaterhotline@westminsterco.gov