Firm numbers are beginning to emerge concerning the cost of opening approximately 29,000 acres in southern Sarpy County for development, and they range from $208 million to $221 million.

The money would fund construction of a network of sewer stations and lines stretching from Gretna in the west to Bellevue in the east designed to treat sewage and deposit treated water into the Platte River. The network would be built south of Highway 370, below a natural ridge line that has rendered the southern part of the county undevelopable because of difficulties associated with pumping sewage north over the ridge line where it could be treated in existing facilities.

Sarpy County Administrator Mark Wayne used an “at a glance” study on Jan. 26 to tell county commissioners that five alternatives were emerging from an ongoing study being performed by HDR Engineering of Omaha. The study anticipates that a treatment capacity of between 6.6 million and 9.9 million gallons a day will be sufficient to serve the residential and economic growth expected to occur below the ridgeline through 2055.

The alternatives are as follows:

• The Baseline Proposal envisions construction of a new regional wastewater treatment network across the county at a cost of $220.8 million, with estimated ongoing operation and maintenance cost of $58.7 million for a total cost of $279.5 million. The main treatment station would be located south of Springfield and would treat 9.9 million gallons a day. It would be supplemented by four satellite stations and five pump stations.

• Alternative 1 envisions expanding the existing City of Springfield treatment plant south of Springfield on Highway 50. The expansion would cost $219.4 million with ongoing operational costs of $58.6 million for a total cost of $278 million. Like the baseline proposal it would include four satellite stations and five pump stations and would treat 9.9 million gallons a day from four satellite stations and five pump stations.

• Alternative 2 envisions expanding the existing Papio Creek Wastewater Treatment Plant, which is a City of Omaha-owned facility along the Missouri River southeast of Bellevue just north of the Highway 34 bridge. The expansion would cost $217.1 million with ongoing operational costs of $116.9 million for a total cost of $334 million. The higher operational costs are attributed to connection charges due the City of Omaha plant. As with the prior two options the expanded facility would be built to treat 9.9 million gallons a day.

• Alternative 3 envisions expanding both the existing Springfield and Omaha treatment plants at a cost of $208.2 million and ongoing operational costs of $74.8 million for a total cost of $283 million. Four satellite stations and five pump stations would feed the plants up to 6.6 million gallons a day.

• Alternative 4 rounds out the proposal, suggesting a blend of an expanded City of Omaha plant and a new regional system consisting of four satellite stations and five pump stations processing up to 6.6 million gallons a day at a cost of $208.8 million and ongoing operational costs of $74.8 million for a total cost of $283.6 million.

Wayne told commissioners that Alternative 1 seemed to be gaining favor among city and county representatives who have been meeting to discuss the way forward.

He said the successful proposal, no matter which it is, will be built in four stages over approximately the next 20 years. Those stages will be known as Phase 1A, Phase 1B, Phase 2 and Phase 3.

He said Phase 1A will likely be accomplished within the next three years and will consist of a $22 million to $23 million expansion of the existing Springfield plant, which is a common requirement of all five proposals.

Phase 1B, he said, will involve an even larger expansion of the Springfield plant at an estimated cost of $28 million and should be accomplished somewhere between 2025 and 2027.

The major cost burden arrives in the 2030 to 2035 time period, Wayne said, when Phase 2 requires construction of a whole new plant south of the Springfield plant with multiple interceptor lines transporting sewage across the county. He said this “really big phase” will cost about $114 million and will require a decision on whether Bellevue-area sewage is to be pumped to the Omaha treatment plant on the Missouri River or west to the Springfield facilities.

Phase 3, which should be completed by about 2040, will expand the system’s total capacity to 9.9 million gallons a day and will bring the total cost to approximately $220 million not counting operational costs.

Wayne said HDR will refine the numbers within the next month and bring the county a final proposal that can be used to draw up interlocal agreements with the cities currently taking part, which are Papillion, La Vista, Gretna and Springfield.

The City of Bellevue, the largest city in the county, has not yet agreed to participate since much of its area sits north of the ridge line and pumps its sewage to the Omaha treatment plant.

Commissioner Tom Richards said since the enormous cost of the project is beyond the capacity of Sarpy County government, he hopes a new taxing authority will be set up to fund the project.

“I just don’t want to create an expectation that the county is going to be able to do this,” he said.

Wayne said creation of a new and independent taxing authority is likely, especially since counties lack the statutory authority to build residental sewer systems. In addition, he said, the state of Nebraska has a strong incentive to provide financial assistance from its Site Building Fund.

“We probably could have one of the largest industrial development sites in the state right along Highway 50 and the interstate, but it needs sewer,” Wayne said. “If the state wants economic development there, I think we can make a pretty solid case for using those funds to build some of this early infrastructure.”

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