AWWA ACE63161

Aurora, Colorado is primarily a residential community of 300,000 people in the easternDenver metropolitan area. The service population is expected to exceed 500,000 peoplein the next thirty years and the City's utility, Aurora Water, has been charged withincreasing the reliability of the current water system as well as providing for the waterneeds of the future community. The highly variable yield productivity of the City's water supply system has beendemonstrated by system performance in the drought conditions experienced in Coloradoand the western United States since 2002. While average annual precipitation in the Cityis about 12 inches (300mm), conditions in 2002 caused extremely low water supplyconditions estimated to occur only once in 300 years.The wet water supply conditions of the late 20th century were not prototypical of the longterm water conditions in Colorado and the stress on the yields in the last 4 years must be considered by the Utility as more representative of what could be observed in the futureas it acquires new water sources and constructs the delivery systems and treatment plantsthat will be necessary.Aurora Water has implemented highly productive and comprehensive water conservationprograms to reduce customer demands, especially during the outdoor irrigation seasonwhen typically half the annual water demand occurred to sustain lawns and trees. TheUtility also acquired permanent and interruptible water supplies from agricultural uses toaugment the low yield productivity of the core water rights portfolio. A combination ofdemand management and new source development approaches have provided near-termrelief and allowed for recovery of carryover storage levels in the City's reservoirs.Continued growth, however, will exacerbate the projected shortages of available watersupplies and so the Utility has initiated a long-term integrated water supply program toensure that adequate service can be provided to customers even under sustained droughtconditions. A comprehensive assessment of the reliability of the water supply system,including core infrastructure, has led Aurora Water to develop a 10 Year CapitalImprovements Program exceeding $1.4 billion in system improvements and expansionsto serve the community's needs. It has also embarked on a major expansion of the rawwater supply system by recovering reusable return flows downstream from the City andexpanding new agricultural water leasing programs to provide supplemental yield indrought years. The City is also acquiring new water rights, largely through transfers ofagricultural water sources, to provide firm yield.As new sources of water are developed on river systems downstream from a majormetropolitan area, the Utility is implementing multiple-barrier water treatmentapproaches to protect public health and meet demanding acceptance levels from acustomer base that has traditionally been served from first-use mountain water sources.This investment by the community is causing significant and sustained increases in wateruser rates and connection fees because the Utility provides services on a "cost-of-service"basis and by Colorado's Constitution, cannot access alternative tax sources to reduce therequired increases in utility bills.This confluence of natural events, level of service and growth, a fundamental shift fromdevelopment to reallocation of previously developed beneficial water uses and localfunding of required capital improvements creates many challenges for today's UtilitiesDirector. This paper describes how Aurora Water is progressively addressing thesechallenges in providing adequate levels of service to current customers while positioningthe community for future needs. Includes figures.

Product Details

Edition:

Vol. - No.

Published:

06/01/2006

Number of Pages:

13

File Size:

1 file , 2.4 MB