Board moves design forward

Seeley Lake Sewer

SEELEY LAKE – The Seeley Lake Sewer District Board gave Great West Engineering the go-ahead to work toward completing the final design of Phase 1 of the collections system and the wastewater treatment plant during an engineering work session Sept. 24.

The board also kept the force main route going up Cedar Lane, discussed the required user agreements, RV dump stations and voted to obtain updated construction cost estimates for Phase 3 and 4 of the collection system.

Great West Engineering's Amy Deitchler, PE, presented the board with the current design that is approximately 60 percent completed.

The project is split into two separately bid components, the wastewater treatment plant and then Phase 1 of collection system including the force main. Deitchler explained that companies that specialize in building treatment plants would most likely subcontract out the work for the pipeline if they were awarded the entire project. By utilizing separate bids, the District can save the subcontracting fees.

Most of Phase 1 of the collection system is gravity fed to a single large lift station located near the intersection of Cedar Lane and Highway 83. A small section of properties fronting on Highway 83 between Redwood Lane and the Seeley Lake Chicken Coop will be serviced with a small diameter pressure system. This was done to avoid requiring 20-foot deep manholes in a narrow alley. Approximately 20 properties in the phase will also require onsite grinder pumps to connect and will be included in the bid.

Service lines from existing houses to the collection system and abandoning existing septic tanks are included in the bid. Vacant lots will have a stub out built into the system for future connections.

Service line restoration is currently not included. Adding restoration back into the bid was brought up but Director Davy Good said he would recuse himself from the topic because he owns a landscaping business. With one vacancy and Director Mike Boltz absent, President Beth Hutchinson and Vice President Troy Spence were the only two available to vote. Further discussion was put off, as the District by-laws require three votes affirmative for any action.

Deitchler said the lift station will be initially sized to take waste from Phase 1 and 2 of the collection system and then either new impellers or larger pumps will most likely be installed when Phase 3 is constructed.

From the lift station, the force main is designed to travel east on Cedar Lane to the intersection of Cedar and Tamarack Drive. The main will then continue east across private property where it will cross Morrell Creek and then across the northern edge of Seeley-Swan High School's property. Near the eastern edge of the high school's property, the main will turn north onto state land and follow the service road to the treatment plant.

The force main route has been a topic of discussion at several previous meetings. Some board members have been adamant that the route was changed to go south to Locust Lane and then up to the high school instead of heading east on Cedar Lane.

Deitchler said that while Great West did receive an inquiry into changing to Locust Lane and produced a comparison between the two routes, Great West has never received instruction from the District to make the change in the design. Because the change was never communicated to Great West, all design work done has been for the original route on Cedar Lane.

Deitchler said the change could still be made if it was desired or if the District is unable to get easements across the private property. The District has had some discussion with the landowner but nothing has been finalized. The board discussed some of the pros and cons of making the change.

The designed route up Cedar is nearly at the maximum lifting capacity of the main lift station. The alternative route would add nearly 3,000 feet of pipe and require an additional lift station. Having two lift stations would mean they could be smaller, however, the second lift station would add operating and maintenance cost.

Only a very preliminary design has been done for the alternative route. Survey work would need to be done along Locust Lane after the intersection of Tamarack Drive whereas surveying has been completed for the other route.

The alternative route is estimated to cost up to $600,000 more based on the pros and cons of the previously produced comparison.

Hutchinson asked if having the second lift station near the high school would allow for the school or future development to be added on the east side of Morrell Creek.

Deitchler said that the high school, which is not currently in the Sewer District, could be connected to the system either way without having to recross the creek. She said it is not the best practice to connect into the force main but it is possible or the school could connect to the second lift station if the alternative route was taken.

Deitchler explained that the sewer system is being designed to accommodate the current District properties. Any future development, either by subdivision within the District, developing a property beyond its current use or by properties outside the District joining, would have to be reviewed to see what upgrades would be needed for the added wastewater flow. Those upgrades would have to be paid for by the developer.

District Manager Greg Robertson recommended the District keep the current route due to it being a half million dollars cheaper. He doesn't think the required easements will be an issue but he has been holding off on attaining them until the board made a final decision.

Deitchler said the main advantages she saw to keeping the route over Cedar was having just one lift station to maintain. The added time for completing the additional surveying, engineering and environmental permitting is also a concern for Deitchler.

The proposed treatment plant is located on state land a quarter mile west of the Seeley Lake Airport and half mile north of Airport Road. A little more than half the 25-acre site will be fenced.

The treatment plant structures will only occupy about an acre of the land inside the fence. Structures include an office/lab, headworks and UV/blower buildings and the treatment basins. There is room to build additional treatment basins if the future growth demands it.

Previously, the treatment basins were to be covered with a greenhouse but it was taken off to save costs. Deitchler said that very few treatment basins are covered in the state because they are expensive and without proper ventilation they have corrosion problems.

The infiltration system for disposing the treated wastewater consists of six zones and will be on three and a half acres. Initially four zones will be constructed to service Phase 1 and 2 of the collection system and then two more zones will be added as Phase 3 and 4 of the collection system are built.

The sewer system is not designed to take RV waste without significant pretreatment. Deitchler said that the board previously decided that only residential strength waste would be accepted.

While restaurants, laundromats and many other business wastes are classified as residential, RV waste falls outside the parameter. RV waste typically contains many added chemicals that can upset the biology of the treatment plant. Septic pumper trucks will also not be permitted to dump into the system.

The three present board members voted to instruct Great West to continue designing Phase 1 of the collections system and the treatment plant to the 90 percent design. The motion included keeping the force main route going up Cedar Lane.

Great West now has 120 days to complete the 90 percent design and submit it to the Montana Department of Environmental Quality for review. Deitchler said the District should still be on schedule to have the project ready to bid this winter with construction able to start in the spring.

In other business, President Hutchinson had requested Great West provide an estimate for updating the construction estimates for Phase 3 and 4 of the collection system. Hutchinson said that despite the feedback that estimates are not needed for people whom attended the last board meeting, there is still strong interest from residents in the District to obtain estimates.

Deitchler said it would cost $4,000 to come up with a "pretty detailed cost estimate." She cautioned that without more accurate surveys it was impossible to know all the locations of houses that would need grinder pumps and that the estimates would be outdated within a few years. It would only be a best guess based on current topographic maps.

"I think that the public deserves to have information that is comprehensive," said Hutchinson.

Spence agreed and made a motion to fund obtaining the estimates. Good seconded the motion after confirming with Deitchler that providing estimates would not hold up the timeline of Phase 1's design. The motion passed with all three present voting for it.

The board also asked Deitchler for her thoughts on collecting the sewer user agreements required by Rural Development (RD) in the letter of conditions for the funding package. There was a disagreement between board members at the September board meeting as to the timing of collecting agreements.

Deitchler said the board could start collecting user agreements at any time. The letter of conditions states they must be collected prior to the project being advertised for bids and Deitchler suggested they get started sooner than later. Great West has not been contracted to provide assistance but could work up a contract to do so. Great West has examples of user agreements provided by RD that Deitchler said she would forward to the board.


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