High Mountain Operations
The City owns and operates six mountain reservoirs
in the Cache La Poudre basin year round. Some are located near the top of Cameron Pass. Water Resource Division staff work with state water officials to capture water in City storage reservoirs during the spring snowmelt and then release the water as needed to meet Greeley’s water demands, which peak in June, July and August. Greeley water may travel 45 miles before it is delivered to the Water Treatment Plant
. City staff who operate the high mountain reservoirs work in remote areas in all weather conditions.
High Mountain Reservoirs
The Supply division's three full-time employees and one summer seasonal employee manage Greeley's High Mountain Reservoirs. All but one of the dams are between 9,000 and 10,000 feet in altitude. Dam safety and monitoring, along with water releases, are primary summertime duties. Milton Seaman and Barnes Meadow reservoirs are not usually emptied. Seaman water is typically used for drought protection, and Barnes Meadow is reserved for winter releases to the treatment plant. Supply employees monitor and regulate Barnes Meadow three times a week from Nov. 1 through March 30. This entails snowshoeing into the dam and digging through snow that is often 3-4 feet deep and then breaking ice 2 feet thick to read the gage.
In mid-April the City plows access roads to reach Hourglass, Comanche, Twin and Peterson reservoirs. This can take up to a month, depending on the snowpack. The road to Peterson is two miles long but has taken as long as two weeks to plow due to12-15 foot snowdrifts. After the roads are plowed, and when allowed by the state, the reservoirs are filled, usually by mid-July snowmelt.
The City of Greeley participates in snow surveys from January through May with the State Engineer's Office and the City of Fort Collins. The surveys give a fairly accurate projection of what to expect for the coming spring and summer water supplies. For the Water Reservoirs Division, data is collected to record precipitation rates, melting rates, and the total water content of the snow. This gives staff an idea of how much water can be stored in the reservoirs. It will also forecast the potential for impending drought. Deep snow doesn't necessarily mean a good runoff. A snow core sample measures the water content.
Snow surveys are completed within five days of the end of each month. It takes three days to go to each of the survey sites with 2-3 different snow courses at each site.
Using water supply projections helps to determine which water from the City will be used at the Bellvue Water Treatment Plant. Colorado Big Thompson (C-BT)
water can be utilized at the Boyd Lake Water Treatment Plant from April 1 until Oct. 30. This gives flexibility to the operation when there is a lot of turbidity in the Poudre due to runoff. The amount of water brought into the plant is determined by demand. A balance is achieved by releasing from the high mountain reservoirs or C-BT system to match production needs at the treatment plant. The Supply Division is able to maximize water utilization by closely monitoring supplies and demands.
Along with the physical aspects of maintaining Greeley's reservoirs, the Supply Division also tracks the water according to the decrees and intended uses. Exchanges with irrigation companies and water utilities are also a vital component of the operation of Greeley's high mountain reservoirs.