Testing of wastewater treatment plant to begin Monday
WILLMAR -- The time is nearing to test whether Willmar's new wastewater treatment plant located west of the city operates properly.
Plant contractor Graham Construction Services on Monday will begin a seven-day test known as a systems demonstration.
Graham is required under the contract with the city to demonstrate satisfactory operation of specific equipment systems and associated facilities before the plant can be considered to be substantially complete and the city can accept ownership.
During the test, water will be run through the plant. Five of the plant's seven systems will be tested during the demonstration. System 6, the solids handling system, and System 7, the solids storage system, will be checked out after the plant is treating waste.
John Bryant, lead resident project representative for the Willmar office of Donohue and Associates, the project's engineers, said seven days is a logical period of time for a test.
"There is always a test-out period on any waste treatment facility that makes it run in this manner before substantial completion, and seven consecutive days is a good working time to prove the system out,'' Bryant said.
Donohue will consider the demonstration successful and complete when systems operate properly for seven consecutive days without significant interruption.
If there is an interruption, such as a major process that functions incorrectly, the seven-day run will start over after the problem is corrected, Bryant said.
If the demonstration is satisfactory, Donohue will recommend substantial completion -- except for systems 6 and 7. If city officials concur with Donohue's recommendation, the City Council will be asked to approve substantial completion.
The council meets Monday night, but the test run begins Monday and won't be completed until Aug. 23. The next council meeting is Sept. 7. In an effort not to delay the city's taking ownership of the plant, Donohue will ask the council Monday night to consider a resolution to approve substantial completion, except for systems 6 and 7, provided Donohue recommends and staff approves it.
Bryant said seeding of the new plant with the millions of microbes that will digest and break down the waste will start after substantial completion. The seeding will be done at a controlled rate from the old plant, sent down the interceptor line, to the new plant.
The first "food'' transported to the plant will be industrial waste, a process that will take about 10 days to two weeks. After that, municipal waste will gradually be introduced from various pumping stations.
As more "bugs'' grow to interact and digest the waste, more municipal flow will be directed to the new plant. After six to eight weeks, all municipal waste will be flowing to the new plant, he said.
Bryant is pleased the multimillion-dollar plant is nearing substantial completion. The project is six weeks ahead of schedule. He said warmer temperatures should accelerate the growth of bacteria and provide a faster startup.
"I hope at the end of this the city and council and people of Willmar feel like it was successful and really benefited the city by moving the treatment plant out,'' he said.
Council approval of the substantial completion resolution was recommended by the council's Public Works/Safety Committee. The council will receive a report on the committee meeting.
In other business Monday, the council will:
- Consider an ordinance providing for tree inspection and eradication of tree diseases and pests.
- Take comments from the public during the open forum.
- Receive reports from the Finance Committee and Community Development Committee meetings.
- Consider special assessments for unpaid grass mowing and unpaid ice and snow removal.