Arkansas - Las Animas Sanitary Sewer System Improvements_Water Activity Summary

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city. Based on the fact the neighboring correctional facility is in the middle of an expansion coupled with the projected population increase, the city’s corresponding water demands will increase. Increases are expected to jump to 546,700 gpd for an average day demand while the maximum day demand is anticipated to increase to 1,157,200 gpd by year 2030. This increase results in a water shortage gap for the city in both of its raw and treated water systems. The City of Las Animas has undertaken a comprehensive Preliminary Engineering Report (PER) evaluating its wastewater system, specifically focusing on the collection system and the associated lift stations and force mains servicing the city. The study was expanded to cover the wastewater treatment plant (WWTP) as a result of the local correctional facility’s proposed expansion that will more than double its capacity. When the correctional facility reaches its inmate expansion capacity, the added wastewater loadings on the WWTP will not be detrimental as a result of the facility’s available capacity. However, the study did reveal critical needs throughout the collection system and lift stations. The city’s main lift station was determined to be in need of replacement due to deteriorating conditions of the wet well, the influent and effluent piping extending underneath the adjacent railroad property and tracks, and the need to move the lift station to the north side of the railroad right-of-way. In addition to the city’s main lift station, the city’s north lift station is also in need of repair. Repairs include lining the concrete wetwell, installing controls and alarms, a new auto-dialer, chart recorder and a new magnetic meter. The lift station improvements in addition to the installation of a refrigerated composite sampler at the wastewater treatment plant comprise Priority No. 1’s improvements. The vast majority of the collection system appears to have been installed in the early 1900s and consists of vitrified clay pipe with brick and mortar constructed manholes. The components of the system programmed for replacement contain 12-inch, 10-inch and 8-inch diameter piping. There are several of these segments that require quarterly, semiannual and annual attention in the form of jet rodding. The jet rodding typically produces large pieces of roots in addition to numerous pieces of broken clay pipe. The review also defined the most problematic collection system segments where structurally failing VCP exists together with extremely flat grades, reverse grades and low spots resulting in significant ongoing sludge accumulations and substantial root intrusions. Those segments incorporated into the study’s priority list represent the most severe of the city’s overall collection system. Several additional segments not included in the listing also warrant replacement, but are not incorporated as a result of realistic budget limitations. Priority Nos. 2 through 9 are those segments that pose the potential of actual structural failure and represent significant maintenance obligations on the part of the community. The project consists of replacing those segments of the city’s sanitary sewage collection system that fall in the Priority No. 2 through 4 recommended work. In the event project funds are available to accomplish additional work, added segments will be incorporated for replacement in the order of their prioritization contained within the study. In addition, one of the priorities contained within the study is the removal of accumulated biosolids within Cell No. 1 of the treatment facility. The project includes replacing several sections of the city’s sanitary sewer collection system, rehabilitating the existing north lift station, replacing the South lift station and installing a refrigerated composite sampler at the wastewater treatment facility. The initial work will consist of Priorities 1 through 4. The hope is that additional replacement work can be undertaken to address the additional severe problems that exist within the system. The specific goals of the project include: 1. Reduce the amount of infiltration and exfiltration from the sanitary sewer mains thereby enhancing ground water quality and increasing water quantity. 2