By Sara Jerome,
A new study builds evidence for a fact that water professionals already know: Nitrate pollution is a growing cost burden for water utilities.
A new report from the Northeast-Midwest Institute analyzed water quality and treatment cost data over a 10-year period from three water utilities in the Mississippi River Basin, including Des Moines Water Works, City of Decatur, and Aqua Aqua Illinois Vermilion County.
The study found that nitrogen concentrations tended to increase over the study period, resulting in a greater number of daily exceedances of the nitrate MCL.
“Daily exceedances were significantly higher during the second half of the study period. A 45 percent reduction in the intake nitrate concentrations would virtually eliminate exceedances, but even a modest 10 percent reduction would bring down exceedance by 20-33 percent,” the report found, per a summary of the report.
The report zeroed in on the enormous costs faced by water utilities as a result of nitrate pollution. A few findings illustrating this point, per the summary:
- Capital expense is a significant component of the overall cost of nitrate treatment at the three utilities.
- In years when influent nitrate levels were the highest, utilities spent 4-9 percent of their overall operating budget on nitrate treatment.
- Smaller utilities face an undue burden of nitrate pollution in drinking water sources.
- Conservation programs have the potential to limit some of these costs to utilities, although the extent of their impact will depend on a variety of factors specific to the watershed.
Eric Heath, senior policy counsel for the Mississippi River Basin Program at the Northeast-Midwest Institute, described the findings in an editorial in The Hill.
“Not only is it expensive to remove nitrate pollution from water, but it also requires a significant capital expense to build the necessary treatment facility. This means small communities will have to take on millions of dollars in new expenses so that their residents can pay more to simply have safe drinking water,” he wrote.
Des Moines Water Works, one of the utilities in the study, has attempted to fight the cost burden of nitrate pollution in court. Des Moines Water Works waged a lawsuit against agricultural drainage districts in attempt to hold farming interests accountable for the steep price of treating nutrient pollution, but the utility lost in court.