DARROW — A new $2.1 million sewer pipeline in southeastern Ascension Parish that’s sending treated wastewater over the levee and into the Mississippi River is expected to become the backbone of a regional public sewage treatment system. 

Creating such a system has been a longtime goal of generations of Ascension Parish leaders, who say the new pipeline, built through the U.S. Army Corps of Engineers, is an important initial step toward that goal. Parish leaders eventually want a sewer system that would discharge much of the parish's treated wastewater into the Mississippi River rather than releasing it into smaller parish streams and waterways.

"Ascension Parish has worked with the Army Corps of Engineers for over a decade to start sewer projects," Parish President Kenny Matassa said during a ceremony with parish, state and federal officials Wednesday near the pipeline discharge point. "Under my administration, talk became a reality, and today we cut the ribbon on our first construction project."

For years, private systems treated sewage from mushrooming residential subdivisions in Ascension that was discharged into local bayous. State environmental officials warned the parish that tightening restrictions would one day limit the amount of effluent that could continue to go into those waterways. 

The goal, environmental officials and others have said, should be to send treated wastewater to the Mississippi. With its much higher water flow, the big river can more easily dilute lingering nutrients that impair the aquatic health of smaller streams and rivers.

For now, the new pipeline, which has been in operation for the past two months, carries treated wastewater from the sparsely populated Hillaryville area of southeastern Ascension over the levee and into the river. Treated wastewater from that area had been going into Bayou Conway and ultimately the Blind River.

Bayou Manchac, much farther to the north and in more heavily populated areas of Ascension than Hillaryville, has also been impacted by the discharge of wastewater from a wide swath of subdivisions that sprouted in that part of the parish, including Prairieville and Dutchtown. The state historic and scenic waterway has been left in what environmental regulators describe as an impaired state. 

While a regional solution for Manchac has yet to be realized, the new pipeline in Hillaryville points a path to the future for wastewater treatment, officials say.

"This is the first time treated wastewater is actually leaving Ascension Parish and not staying in the parish to go to local waterways here, where it previously has been going," said Col. Mike Clancy, commander and district engineer for the Corps in New Orleans.

Clancy said the 8-inch-diameter pipeline and a related pump station were designed and built through the Corps' environmental infrastructure program established under continuing congressional authority dating from the early 2000s.

With funding shepherded by Congressmen Garret Graves, R-Baton Rouge, and Cedric Richmond, D-New Orleans, the Corps paid for 75 percent of the project’s cost. Parish government provided the 25 percent match. Before construction, an additional $300,000 was spent through the same Corps program for design.

The new pipeline to the Mississippi also marks perhaps a rare instance in which parish government finds itself ahead of coming residential development instead of always struggling to catch up.

The new pipeline currently handles treated wastewater from about 250 to 300 parish government sewer customers in Hillaryville and sends the treated water 4,000 feet south along Marchand School Road to the river, Clancy and parish officials said.

With the help of a $5.2 million Community Development Block Grant that was part of a storm recovery package after Hurricane Gustav in 2008, the parish has plans to expand the Hillaryville treatment plant and build new collection lines. The expanded plant and new pipeline to the river will then serve neighboring homes and subdivisions in Darrow and Astroland.

With even more parish and private developer funding, parish official added they want to also serve the new nearly 800-home Riverton subdivision under construction just down the highway from the newly built pipeline, as well as a planned commercial project.

Parish officials added there is potential to serve additional new development farther north along La. 44, where additional subdivisions are planned or under construction.

"We've got unlimited things you can do, and we're looking at all of them and, of course, we look at dollars, and this was first the phase," Matassa said in a later interview.

Miles to the north of Hillaryville and Darrow, in Prairieville, the parish has struggled to find a way to set up a public regional system where private providers already control the customer base and infrastructure.

On Tuesday, Parish Council members groused about the proposed terms of a contract to have private sewer provider Ascension Wastewater Treatment handle sewage treatment from more than 400 homes along the heavily developed but still growing La. 73 corridor in Prairieville, where a new subdivision and new micro-hospital complex are being built or are planned.

The state widened La. 73 a few years ago. Due to state environmental rules and the use of federal funds for the road, the parish had to install new sewer collection lines under the expanded highway to receive partially treated wastewater from existing homes and businesses along La. 73.

The new sewer lines were built and are accepting the wastewater, but the parish has been unable to find a sewer treatment plant to finish off the cleansing process and so has been negotiating with Ascension Wastewater to expand and use one of its existing plants.

Among the council complaints Tuesday are the possible size of monthly user fees for Ascension Wastewater and a $306,200 onetime fee the parish must pay for expanded sewer plant capacity. The council members noted the payment appeared to be without a provision to credit the parish should it ever buy out the company as officials have tried to do in the past.

“To me, that’s like I’m buying a car for somebody. I give them the car. I sign the car over to them, and then buy the car back from them two years later,” Councilman Travis Turner said.

While the new line in Darrow is finished, the proposed contract for La. 73 remains in negotiation after Tuesday night. Partially treated wastewater from La. 73 also continues to wind up in local waterways with a state deadline for a solution approaching.

Follow David J. Mitchell on Twitter, @NewsieDave.