Purdy city leaders got direction about how to address the city's ongoing sewer system problem during recent talks with representatives from the Missouri Department of Natural Resources (DNR). City council members and their engineer discussed the issue for the first time with DNR since voters rejected a proposed $2.5 million bond issue in June.
"We had a long meeting," said Glen Davidson, engineer with Allgeier, Martin and Associates who helped design the proposed fix to the east lagoon. "We did not walk out with all the issues resolved and a clear plan set forth."
"We didn't get any answers," said Mayor Ron Dutra.
Clarification was provided over a couple of the trigger issues that prompted DNR's insistence that changes be made at the east lagoon.
When a new wastewater permit was issued to the city, standards for effluent quality were significantly increased. Under the old standards, the lagoon had been designed to overflow into a dry creek under high water conditions. Any effluent now leaving the lagoon is expected to meet standards for losing streams, a higher quality level than the lagoon system is believed to be able to achieve.
Under the current operation, effluent is filtered by being irrigated into a field, and impurities are removed as water sinks through the dirt and back into the water table. The quality of effluent leaving the lagoon is not monitored except by several test wells in the vicinity.
One of the test wells has consistently shown excessive levels of nitrates. Public Works Superintendent Teddy McIntire said the well has always measured high and was generally considered an aberration, considering all the other wells showed acceptable number.
"This is an issue of non-compliance," Davidson said. "That's how they see it. The well is a big issue with them."
DNR officials encouraged the city to take underground measurements upstream from the well in question. Davidson said new tests could provide answers as to whether the city's system was causing the excessive nitrate readings or not. Greg Perkins, water pollution engineer for DNR's Springfield office, expressed doubt that the pollution problem was coming from the city.
If the off-site monitoring well showed the city's lagoon was not responsible for the high nitrate readings, Dutra said the city would still have to address the overflow issue.
"We're going to have to do something," Dutra said.
During the second public hearing on the proposed sewer system upgrade, several residents had encouraged the city to work on reducing the amount of storm water getting into the sanitary sewer system. A reduction was viewed as a potentially less expensive way to decrease the potential for a lagoon overflow.
"DNR was not able to tell the city, nor were we (at
Allgeier, Martin) that work on I&I (inflow and infiltration) alone would necessarily address the problem," Davidson said. "No one knows enough about the nature of the I&I problem to say 'if you do this, this will happen.'"
The city's plan to work with Ace Pipe Cleaning to rehabilitate sewer pipe in much of the west half of the city was mentioned and viewed as a good step.
Davidson and his team agreed to look at other options for improving the sewer system. The plan had called for upgrading pumps, installing two miles of pipes to expand the irrigation field to a much broader area and reduce the amount of flow used in irrigation to avoid run-off pollution. Davidson planned to look at different pipe sizes and prepare some ballpark figures on cost differences.
"DNR gave us some suggestions to consider. We didn't identify any alternative that showed any promise for being less expensive," Davidson said.
Council members have an August deadline for deciding whether to put the sewer proposal or some variation back on the ballot for voters to consider in November. Davidson planned to have details on alternatives ready for the council's Aug. 9 meeting so that a decision of putting a proposal on the ballot could be made then.
"DNR is not impatient with the city at all," Davidson said. "Neither did they say, 'Don't worry about it. You have plenty of time.' They wanted the city to move forward as soon as possible. I may be reading between the lines, but it seemed to me enforcement may not be too far off."
Smoke testing of sewer lines on the west side of town has been scheduled for the first week in August, as part of Ace Pipe Cleaning's effort. Letters of violation should be mailed to property owners whose private storm water lines are found to be connected to the sanitary sewer system.
Dutra expected aldermen would have alternative proposals from Davidson and a report from Ace Pipe Cleaning by the time of the meeting. He expected aldermen would be able to decide on a November ballot proposal.
"Hopefully working on I&I and the plan we worked on the first time will deal with the problem," Dutra said.