Castle Rock's water is moderately hard, so faucets here tend to collect scale that stiffens handles and clogs aerators. Most problems are solved with a cartridge or seal replacement, though heavily scaled faucets may be better replaced. Call the number on this page to be connected with a local plumber in Castle Rock.

Castle Rock at a glance
Castle Rock Water, the town utility, relies mostly on deep Denver Basin groundwater wells, along with renewable supplies such as Plum Creek diversions. Its 2026 report gives average hardness of 100 ppm, with a range of 61 to 182 ppm, and calls the water moderately hard; the town's FAQ lists 6.6 to 10.8 grains per gallon. The town disinfects with chloramine. Some addresses with a Castle Rock mailing address, such as The Village at Castle Pines, are served by other districts.
What to do now
- Shut off the water at the faucet. Turn the stop valves under the sink clockwise. If one sticks, do not force it; close the main shutoff instead.
- Protect the cabinet. Clear it out and dry any standing water so the wood does not swell.
- Pin down the leak. Look at the spout, handle base and connections underneath with a flashlight and a dry paper towel.
- Clean the aerator for weak flow. Unscrew it, soak it in vinegar to dissolve scale, rinse and reinstall.
- Note the brand and style. One lever or two, pull-down or fixed spout, and any logo on the handle.
- Know the street-side contact. For a water emergency outside the house, Castle Rock Water's line is 720-733-6000; after hours, press 1.
Symptoms and likely causes
| Symptom | Likely cause |
|---|---|
| Handle grinds or is hard to turn | Scale on the cartridge |
| Drip after the handle is off | Worn cartridge seals or a washer and seat |
| Spray fanning out sideways | Mineral buildup in the aerator |
| Water at the base of the spout | Dried or cracked O-rings |
| Puddle under the sink | Supply line, stop valve or drain connection |
| White crust around the faucet base | Slow leak leaving minerals as it dries |
What drives the cost
- Whether the faucet can be rebuilt or needs replacing
- How much scale has to be removed to free the cartridge and nuts
- Parts availability for the brand
- Replacing worn stop valves or supply lines at the same time
- Access in the cabinet and the number of fixtures on the deck
On softeners: Castle Rock Water does not recommend them because of the salt they add to wastewater. Regular aerator cleaning and choosing faucets with easy-to-replace cartridges are practical alternatives.
Faucet Repair questions in Castle Rock
Does hard water shorten the life of faucet cartridges?
When does replacing a faucet make more sense than repairing it?
Does the disinfectant in our water matter for a filtered-water faucet?
Can I buy my own faucet and have a plumber install it?
More plumbing services in Castle Rock
Faucet Repair nearby
Helpful guides
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