S&WB projects could hasten bayou’s revival

29th September 2014   ·   0 Comments

By Susan Buchanan
Contributing Writer

Freshwater fish are jumping again in Bayou Bienvenue, the former cypress-tupelo swamp spanning the Lower Ninth Ward and St. Bernard Parish. Fresh water began replacing salt water when the Mississippi River Gulf Outlet or MRGO was closed in 2009. Projects started by the Sewerage & Water Board of New Orleans several years ago will use treated wastewater to hasten the bayou’s comeback, Madeline Goddard, S&WB’s deputy general superintendent, said last week. These projects are also intended to protect surrounding land. Goddard spoke at a Sept.20 conference on coastal restoration, held in Audubon Park and sponsored by the City of New Orleans and the National Wildlife Federation.

Canal construction in the late 1950s and 1960s allowed salt water to enter the bayou, killing vegetation and impacting fish. “But since the closure of the MRGO, freshwater fish are back in the west end of the bayou as you come into the Lower Nine,” wetlands specialist John Taylor, with the Lower 9th Ward Center For Sustainable Engagement & Development, said last week. “We’re catching perch and green trout, and alligators have returned to eat these freshwater fish.” Before the MRGO was closed, Taylor filled hampers with crabs from the bayou’s then-saltier water. “But the crabs are gone now,” he said.

Aquatic plants, particularly lilies, have returned too. “But trees can’t just grow back,” Taylor said. “They have to be planted, and different groups of people have been out here doing that.” He’s fished the bayou since childhood and before the U.S. Army Corps of Engineers began MRGO construction in 1958.

A S&WB effort, called the Central Wetlands Assimilation Project, is intended to hasten the bayou’s recovery by piping in disinfected municipal wastewater from the East Bank Sewage Treat­ment Plant adjacent to the bayou, Goddard said. St. Bernard Parish, the state, a federal-state entity called the Delta Regional Auth­ority, Veolia Water North America, and Tulane and Xavier universities are project participants. The S&WB and Veolia Water partnered in 1992, when the city’s wastewater treatment operations were contracted to that company.

EBSTP’s wastewater, which is discharged now into the Missis­sippi River, contributes to a large dead zone in the northern Gulf of Mexico. By rerouting that waste, nutrients won’t be squandered but instead will stimulate the wetlands. Suspended solids in the wastewater are expected to help wetlands’ sediment grow. An increase in underwater soil will be accompanied by root growth.

The EBSTP is experimenting with charged ferrate ions as oxidizing or disinfection agents, in place of chlorination, to prevent negative impacts from effluents, Goddard said at the coastal conference. Ferrates can oxidize and remove pharmaceuticals, shampoo and other personal-care products from wastewater so that they don’t harm fish or anyone eating their catch.

Demo sites have been built in a section of the bayou adjacent to the EBSTP. These sites will use the plant’s effluents, bio-solids and incinerated ash to promote the bayou’s health, Goddard said. In St. Bernard, the EBSTP’s treated effluent will be used for the bayou’s A2 area. In both Orleans and St. Bernard, dredge material will be applied to raise the bayou’s elevation to support new trees.

“Science for a long time has recognized that correctly treated wastewater effluent can benefit restoration projects,” St Bernard Parish water quality superintendent Jacob Groby III said last week. Few facilities, however, are located adjacent to wetlands. “The Sewerage and Water Board’s East Bank Facility and the Riverbend Oxidation Pond and Munster Wastewater Treatment Plant in St. Bernard are in just the right locations to send treated effluent” to target areas, he said.

So far, demo test cells have been built, and plans are being finalized for a network of pipes, Groby said. The pipes will carry wastewater from the EBSTP into Unit A2 in St. Bernard.

“The significance of these project is that fresh, nutrient-rich water will flow into a former brackish marsh, where more resilient spe­cies of tupelo-cypress will be planted,” Groby said. “These plantings, along with others, including species of grass, will help stabilize and regrow lost natural habitat.”

A wetlands assimilation ground-breaking ceremony was held by the S&WB on Nov. 10, 2011. Work since then has been running a bit behind, however, because of issues with contractors. When asked about that last week, the S&WB declined to comment.

As for funding, the S&WB re­ceived a $400,000 grant several years ago from the Delta Regional Authority to do feasibility and pre-design project work. The state’s Coastal Impact Assistance Pro­gram or CIAP has provided grants for two S&WB wetlands projects. According to state’s Coastal Protection and Restoration Authority or CPRA, one S&WB project funded by CIAP will take treated wastewater from the EBSTP and use it to nourish created marsh in a St. Bernard Parish section of the Central Wetlands. The Central Wetlands is an area located mainly in St. Bernard between the 40-Arpent Canal levee and the MRGO levee. The other CIAP-funded, S&WB project will treat wastewater with ferrate technology and use it for marsh created in Orleans Parish next to the EBSTP. A total of $12.5 million in CIAP funds have been earmarked for these two projects, and about half of that has been disbursed so far.

Another project using state funds will take wastewater, treat it with ultraviolet radiation, and use the treated wastewater to nourish marsh in the Central Wetlands near St. Bernard’s Riverbend area.

The S&WB has been leading the first two projects while St. Bernard Parish spearheads the Riverbend project. The state is overseeing all three in a broader effort to restore the Central Wetlands. The state’s 2012 Master Plan project “Central Wetlands Marsh Creation – Component A” aims to create 2,010 acres of marsh in the Central Wetlands near Bayou Bienvenue. A recently proposed, federally-funded project under the Coastal Wetlands Planning, Protection and Restoration Act, or CWPPRA, would restore 350 acres of marsh in the area.

So is it safe to eat freshwater fish caught in Bayou Bienvenue? “We don’t test them,” John Taylor said last week. “We just take them home and cook them, and so far no one’s gotten sick.”

This article originally published in the September 29, 2014 print edition of The Louisiana Weekly newspaper.