AWWA MTC57546

Incorporated in 1885, the City of Idaho Springs is located along the I-70 corridor, 18 miles westof Denver at 8,000 ft elevation. It is a popular tourist stop along the way to many ski destinationsand resorts in the Colorado Rockies. The City is located in Clear Creek County that has apopulation of 10,000. The water utility serves approximately 2,200 people with 1,000 serviceconnections in addition to a large number of tourists.The water supply originates from two locations: Devils Canyon (an infiltration gallery) and theIdaho Springs Reservoir via Chicago Creek with a diversion at Mattie Dam. Both supplies aresituated at elevations above the water treatment plant. The reservoir is located 9 miles from thewater treatment plant (WTP) and feeds Chicago Creek that runs adjacent to the WTP. MattieDam is a smaller dam from the early mining period of the area and is located approximately 1/4mile adjacent to the WTP and retains the overflow from the Idaho Springs reservoir. Thebackwash waste generated from the new WTP is permitted to discharge directly into the ChicagoCreek downstream of the intakes.In October 2001, the City underwent a period of poor raw water quality that its late 1960'sconventional water plant could not produce acceptable finished water turbidity. As a result, theColorado Department of Public Health and Environment (CDPHE) imposed a boil water order onthe City. Prior to this incident, the City had been planning to upgrade its conventional plant andhad estimated $7 million in plant improvements to be implemented in phases.Following the boil order, CDPHE indicated that it would not approve a phased approach andessentially required the immediate installation of a reliable filtration system. The City and itsconsultants elected to satisfy this requirement with the installation of a microfiltration system.The City made its decision based on good performance and reliability record of microfiltrationsystems operating on similar water quality sources. In addition, the City interpreted this mandateto have an improved filtration system functional by May 2002 to ensure compliance was achievedprior to the annual spring runoff period. To meet the start-up date of May 2002 the City adoptedan extremely aggressive design and construction schedule. Includes table, figure, appendix.

Product Details

Edition:

Vol. - No.

Published:

03/05/2003

Number of Pages:

11

File Size:

1 file , 1.4 MB