wastewater treatment

JOhn hook /Missourian
Columbia treatment facility.

New standards influence plans for upgrades


It’s been more than 30 years since the U.S. Clean Water Act in 1977 laid out goals for removing toxic chemicals and other pollutants from America’s waterways.

The act “had very high goals for basically going from minimal sewage treatment to a goal of zero discharge into streams,” said Ed Galbraith of the state Department of Natural Resources. “What has happened in actuality is that all states have been working toward that very lofty goal in an incremental fashion.”

Although the goals haven’t been met — Galbraith said that in an ideal environmental world the Clean Water Act would mandate pure distilled water running down streams — he thinks states and cities have done their best to make water cleaner and safer with the money they’ve had.

“The approach was more like, well, how good can we do and what will our finances allow?” he said. “It may not be the full ideal, but it will be what we can do now. Whereas some might characterize it as a delay, a failure to implement the act, it’s really been a systematic working toward the goals laid out by the Clean Water Act.”

The latest stream standards associated with the Clean Water Act — driven by a shift in how the uses of streams are defined and how much they must be protected — are putting financial pressures on sewer utilities across the state.

Those standards place limits on fecal coliform, also called E. coli, a bacteria harmful to humans, and ammonia, a chemical that is toxic to fish and wildlife.

In Columbia, voters are being asked to approve a $77 million bond issue, which includes new equipment to that would remove ammonia.

The Boone County Regional Sewer District is also seeking approval of a bond issue for $21 million, all of which will pay for improvements to meet the new standards.
The new limits are mandated by the state DNR, which is responsible for enforcing the Clean Water Act in the state.

City and county voters will decide on the bonds on April 8.

Customers of the city sewer utility would see a rate increase of 70 percent over five years if voters approve the bonds, and sewer district rates would more than double by 2013. Because the new limits are state mandated, the utilities would still have to pay for improvements if the bond issues fail. The only way to do this would be to pay in cash, which would raise rates even more.

A shift in definitions
A change in 2005 in how the state defines water bodies uses is the driving force behind the new regulations.

There are 15 definitions. For example, waterways for swimming have one of the highest levels of protection for bacterial standards. Other classifications include those applying to state waters in which people boat, fish or wade, but don’t swim; irrigation; livestock and wildlife watering; protection of several types of aquatic life; and habitat protection for other wildlife.

A stream or river can support more than one use. Fish live in rivers or streams where people also swim, but the different definitions help the state decide what criteria must be met to support the water body’s uses.

Before 2005, only about 25 percent of streams and rivers in Missouri were classified for swimming. To receive the whole body contact use definition under the old rules, there had to be evidence that people used the water for swimming.

But the Missouri Coalition for the Environment sued the Environmental Protection Agency in 2005, charging that the EPA failed to enforce a “fishable and swimmable” standard with all of Missouri’s waterways as required under the Clean Water Act.

In the interest of safety, the coalition argued, the burden of proof should go the other way: The state should assume people swim in all streams unless evidence showed otherwise. The coalition settled the lawsuit, and the state agreed to develop new standards.

Under the new rules, about 96 percent of classified rivers and streams in Missouri now fall under the whole body contact designation, Galbraith said.

Before the change in waterway definitions, all treatment facilities that discharged within two miles of a whole body contact waterway had to meet limits on fecal coliform. Now, with so many more waterways defined as whole body contact, more treatment plants must meet that standard.

In 2005, the DNR estimated that the extra treatment needed for sewer utilities to meet the new standards would cost municipalities across the state a total of $350 million, Galbraith said.

“Most facilities have a period of years to phase in and to get the financing in order,” Galbraith said. “It takes a long time to get a bond issue in order.”

The Boone County Regional Sewer District, formed in 1974 to oversee sewers in unincorporated areas of the county, must update 29 of its 46 facilities to disinfect for fecal coliform. It must also monitor ammonia levels, though limits have not yet been imposed.

To meet the new disinfection requirements, the sewer district has three options. It can connect neighborhoods to Columbia’s system or another municipality and no longer discharge directly into a watershed. It can also treat the wastewater with chlorine, which kills pathogens. However, chlorine can also harm wildlife, so other chemicals must be added to minimize these effects. Finally, ultraviolet light can be used to zap pathogens, scrambling their DNA so they do not reproduce.

The sewer district now uses chlorine disinfection in two developments, said Tom Ratermann, the sewer district’s manager, but both of these facilities will close by 2009 because they are being connected to the city sewer system.

Ratermann said that while the state has not prohibited the use of chlorine, the limit for how much can be released is almost unattainable, making ultraviolet light the better option in most cases.

“Chlorine could be the appropriate technology at a certain place, for a certain reason,” he said. “We evaluate on a treatment-facility-by-treatment-facility basis. But my gut feeling is that UV light is the way to go.”