Agenda - Council - 03/09/2021 - Laserfiche WebLink

Home

1. Develop Water Model. Develop a model of the City of Ramsey's municipal water supply system using an industry standard software program. This model will allow the selected consultant to adequately prepare a preliminary design report, and will allow the City to evaluate future operations throughout the system by considering variable flow regimes when water is drawn from different wells and storage tanks at different times, variable water usage patterns by municipal water consumers, and proposed system expansions. 1. Prepare Preliminary Design Report. Prepare a preliminary design report exploring available options and recommending preferred processes for treating known and emerging contaminants that will potentially need to be treated over the anticipated life of a centralized water treatment facility in the City of Ramsey. The report must examine available treatment process options for identified contaminants potentially needing treatment, recommend a preferred treatment process for each identified contaminant, identify required space needs for preferred treatment processes, identify anticipated expansion needs, provide a recommendation as to the required size and preferred location for the facility, and provide cost estimates for constructing and operating the facility over its anticipated life. On October 8, 2019, the Ramsey City Council adopted Resolution #19-248 awarding a contract to SEH Inc. to complete the tasks identified above. SEH, Inc. has since completed a Feasibility Study addressing the three general areas outlined above. The findings of the study are generally as follows. • The TCW aquifer will be able to continue to produce potable water to meet present and foreseeable future demands. • The most cost-effective method for removing manganese and iron from the City's drinking water is chemical oxidation followed by sand filtration. These processes require construction of a water treatment plant. • Based upon an analysis of Ramsey's 2040 water demand, the initial capacity of the water treatment plant should be 10 million gallons per day (MGD), with the ability to ultimately expand to 20 MGD. • Four water treatment plant sites were evaluated including the Fire Station site, Public Works site, Water Shop site, and Vacant City property site. The Public Works site is recommended since it requires the least overall construction costs and offers the greatest operational efficiencies. In addition, in January of 2021 the City of Ramsey's Planning Commission, Economic Development Authority, and Public Works Committee all voted unanimously to recommend City Council approval to construct the water treatment plant on the Public Works site. • Two treatment process alternatives were evaluated including gravity filtration and pressure filtration. Gravity filtration is recommended due to life cycle cost savings, ease of operation and maintenance, and increased flexibility for adding processes. Next Steps The City has been able to continue to supply its municipal water users with safe potable water without interruption by running the three municipal wells with the lowest manganese concentrations continually for almost 2 years now, which has and will continue to cause the existing water supply system infrastructure to wear out faster than normal. The City has been utilizing Wells #5, #6 and #7 since April of 2019. Since such time, we have been running these three wells almost non-stop, which is very hard on moving parts such as meters, motors and pumps. Last fall the City had to repair Well #7, during which time it was out of service. Then early this winter the same repairs were needed to Well #6, requiring this well to be shut down for a month while it was repaired. Luckily, these repairs were not needed during our peak water use time during the summer months when people area watering lawns, filling swimming pools, washing their cars, etc. The City also recently had to replace the water meter at Well #6, and have had ongoing issues with Well #7's water meter. A cooling unit also failed recently in the service cabinet for Well #6, which can cause the well to overheat and shut down. Staff believes the constant use of these wells contributed in large part to the required repairs. We have been lucky so far that the repairs were not needed during peak water use times. If one of the wells would need to be repaired during a peak water use time we would need to rely on another well with higher manganese concentrations, which would increase manganese concentrations throughout the system. Staff therefore recommends moving forward with implementation of the water treatment plant project as soon as possible.