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LAUREL – The City of Laurel continues its search for a new source of drinking water.
Senior project engineer Roger Protzman of JEO Consulting Group Inc., the city’s engineer, provided an update on the search to the Laurel City Council on Feb. 12.
In a follow-up interview, he noted the city’s water demands are currently being met by two water supply wells.
“Both wells meet safe drinking water standards,” Protzman said. “The city has been monitoring nitrate levels in the 2009 well and they have been rising. Samples are taken quarterly according to state protocol.”
He noted the water in the city’s two active wells is safe to drink, even though there have been concerns with rising nitrate and selenium levels.
“Selenium has been stable for the last five years so it is not a major concern, but it is always being watched,” Protzman said. “Nitrate concentrations in one well are more of a concern and are being monitored quarterly. We are still waiting for the first quarter report.”
Mark McCoy is the Laurel city administrator and one of the city’s water operators.
“Mark is always monitoring the wells and planning for the future,” Protzman said. “We must consider both quality and quantity. If one of the two wells were to fail or if one is lost due to water quality, this makes it difficult for the city to always meet all demand scenarios.
“Laurel’s water supply has been adequate, but in the past, the city had three wells, thus providing more reliability,” he said. “One well from 1984 is no longer in service, thus the city now only has two wells.”
The city has drilled multiple soil borings and had three test wells constructed.
“As data has been obtained, none of the sites looks to be a site the city staff or council feels comfortable investing further funds into,” Protzman said. “One site was high in nitrates and two sites were high in manganese.”
He said nitrate levels tend to be variable over time and they have been generally increasing in many parts of Nebraska.
“Once the concentration goes over the limit of 10 ppm (parts per million) – over 10.5 by the state’s interpretation – the city will need to take action by supplying bottled water to nursing or pregnant mothers and those that may have weak kidneys,” Protzman said. “The city will be required by the state to take additional actions to return to compliance. The city has been proactive the last years trying to stay ahead of any situation that might arise.”
Because Laurel’s local well sites have not “panned out,” the city has been looking beyond its boundaries, he said.
“Staff have been collecting water samples where permitted to see if a portion of one of the local shallow alluvial aquifers can be identified as having acceptable water,” Protzman said. “If a site is identified, a soil boring would be drilled, and if aquifer material is found, then a test well is constructed and a water sample collected.
“The state recommends municipalities complete a total water quality scan for numerous contaminants if a site is under consideration for (a) production well,” he said. “We generally start out with a lower cost scan of limited parameters for things such as nitrates, iron, manganese and hardness before the cost of a total water quality scan is incurred.”
All options are always on the table for the city as the search continues, including joining the Wau-Col Regional Water System or building a water treatment plant.
“These options have been discussed (and) considered in past engineering reports and memos,” Protzman said. “Due to costs and complexities, the council would prefer to find a lower cost solution. However, the council is keeping all options on the table. Fortunately at this time, Laurel is not in a position where a decision has to be made.
“Because the council and staff have been proactive in this investigation, we continue to look into all options at their leisure and not on a forced schedule by the state. The council would like to pursue the least cost option that provides the best long-term solution that is highly reliable.”
He explained what the potential costs could be for two of the city’s drinking water options.
“The last cost opinion for Wau-Col was approximately $7.4 million for the piping, water tower and water pressure booster station,” Protzman said. “There are many items with this alternative that require further discussion with many stakeholders to move this alternative forward.
“Water treatment is highly variable depending on the treatment process, and conceptual cost opinions range from $6 (million) to $11 million depending on the technology (and) numerous other variables,” he said.
