Water Department FAQs

Where is the treatment plant located?
The City of Black Hawk operates two treatment facilities. One is located at 1040 Dory Hill Road in Black Hawk. The other is located 2 miles east of Idaho Springs at the Hidden Valley Exit #243 off of I-70.

Where is Black Hawk's water source?
The City of Black Hawk has two water sources. The first is North Clear Creek water, which the Dory Hill Plant treats. The second is Clear Creek water, which the Hidden Valley Plant treats.

How is water treated before going into a public system?
The Dory Hill Plant is a filtration plant. The water is pumped up from North Clear Creek and then is filtered through a micromedia membrane filter. Soda ash is then added to the filtered water for corrosion control. Chlorine gas is also added to maintain a residual for disinfection, which kills any living organisms, such as bacteria and viruses in the finished water. The Hidden Valley Plant also filters the water, but in addition, the water also passes through settling basins before filtration. In the settling basins, chemicals are added to help settle particles out of the water; and other chemicals are added to oxidize iron and manganese. The water is then filtered and disinfected with chlorine gas as a disinfectant.

What type of chemicals are used to treat water?
The chemicals we use for treating water are the following: micromedia membrane - which is used for filtration; Lime (calcium carbonate) -- which is used for raising alkalinity; Carbon Dioxide (C02) - which is used for lowering PH; Soda Ash (sodium carbonate) -- which is used for corrosion control to keep the insides of water pipes from corroding; and Chlorine Gas - which is added for disinfecting the treated water, in other words, it kills any bacteria or viruses that are in the water.

Why Hidden Valley for a new water treatment plant?
1) The abundance of water in Clear Creek
2) The land was easier to acquire adjacent to the Creek

What effect do the mines have on the water?
In recent years, the state and federal government have taken major steps to clean up old mine sites, consequently, the metals and other associated pollutants related to mining have decreased below acceptable limits in the local waters.

How do we get the water to Black Hawk from Hidden Valley?
From the Hidden Valley Plant, the water is pumped via three pump stations. The first pump station is located at the Hidden Valley facility. The other two pump stations pump the treated water over the top of a summit, which is 1,800 feet higher than the treatment plant; and from the top of the summit it flows by gravity to the one million gallon storage tank located on Miners Road in Black Hawk. The total pipeline length is about seven miles.