Protecting Our Watershed

DogWasteStationKeeping our waterways clean

Stormwater runoff is the rain or melting snow that runs off across a yard or street and flows into a nearby stormwater drain, which leads directly to the nearest stream and lake. The runoff is not treated before it enters the natural system. Thus, it is our responsibility to keep our watershed clean. Preventing pollution before it enters the water system keeps wildlife healthier, reduces the need for more aggressive water treatment options downstream and keeps the streams and lakes in which we play more beautiful. View the Castle Rock Watershed Protection District (PDF).

Some ways you can prevent stormwater pollution

  • Utilize Douglas County's low-cost household service for hazardous waste removal, available year-round. 
  • Join volunteers in picking up trash along East Plum Creek at the Spring Up the Creek event held every May.
  • Drop off unused or expired prescription drugs in the lobby of the Castle Rock Police Department, 100 Perry St., during regular business hours.  
  • Dog waste can contaminate stormwater run-off, ending up in our water supply. Dog waste is not a fertilizer and contains harmful amounts of nitrogen, which may spread noxious weeds. In addition, it can spread worms and other parasites, as well as many different illnesses and diseases, including E. coli. Per Town Municipal Code, dog owners are required by law to clean-up their dogs’ waste, and can be fined for failing to do so. 
    • To report violators on public property, please contact the Police Department at 303-663-6100 or report a concern online
    • To report violators on private property, please contact the Douglas County Health Department at 303-660-7401.
    • Sponsor a dog waste station along the Town's trails. More details here.
  • Use fertilizers sparingly. If over-applied, rain carries away the excess nutrients the plants do not need and washes them to the nearest waterway, causing excess algae growth that uses up vital oxygen for fish. 
  • Don’t wash lawn and yard clippings into the street and drains. The excess phosphorous and nitrogen are too much for the natural stream to handle and are harmful to wildlife.
  • Do not (even temporarily) store landscape materials in the street or sidewalk; rock, mulch and soil should be delivered and placed on your driveway. 
  • Clean up automotive and chemical spills using dry clean up methods. One drop of oil can pollute one million drops of water. 
  • Dispose of fats, oils and grease in the trash can. Landfills are equipped to handle these materials. Freeze them for easier disposal.
  • Make sure trash is in the trash can. Keep trash can lids closed, secure loads in open vehicles, and pick up litter in the streets to minimize litter scattered by wind or rain. Sweep and dispose of waste in a trash can instead of using a water hose to clean driveways and sidewalks.
  • Unused or leftover latex paint can be dropped off at some area paint retailers for reuse. Dried out water-based latex paint can be safely and legally disposed of in regular household garbage. Mixing the paint with kitty litter, concrete-mix, or soil will help speed the drying process. Empty or dried-out cans of paint can be discarded in the trash if the lids are removed. 

If you see illegal or accidental dumping, please contact our Stormwater Hotline at 720-733-2235 as soon as possible.  

  1. Spring Up the Creek
  2. Household Chemical Roundup
  3. CLEAR

Spring Up the Creek

This annual springtime event, held each May, started in 2003 when a group of energetic volunteers took it upon themselves to clean up areas of East Plum Creek and Sellars Gulch. Since then, the clean-up has grown to include hundreds of volunteers cleaning various drainageways throughout Town. Volunteers are given gloves, bags and transportation if required. Through sponsorships, the event provides free T-shirts, breakfast, kids’ crafts and a host of other activities.  

Watershed Protection Map

Castle Rock lies within two watersheds: Chatfield and Cherry Creek. The Castle Rock Watershed Protection District map (PDF) was updated in 2021 and adds components of the Cherry Creek Watershed to the protection district consistent with the new water facilities Castle Rock Water has added in this watershed. Per municipal code section 4.02.020 -Jurisdiction Map, this map has been administratively updated in accordance with code and is available with the Town Clerk and on the website for inspection.