|
The Davis Pond water project has seemingly been in the planning
and construction phase forever. At a cost of $119.6 million, the
world's largest freshwater diversion project started in November
1996, and is now in the final phase before being able to work
at full capacity.
“We're addressing some of the issues of the ponding area and
on the west side of the guide levee,” said Chuck Villarubia, coastal
resource science supervisor for the Department of Natural Resources.
“We're hoping that this work can be completed by the end of the
year.”
Many thought the project would be well on its way to doing what
it was intended to do after the ribbon-cutting ceremony held in
March of last year.
“When you're speaking of a project the size of Davis Pond, it's
sometimes hard to predict some of the things that have occurred,”
Villarubia said. “The biggest difference in Davis Pond and Caernarvon
is the two major bodies of water in (Lake) Cataouatche and Salvador.”
 |
| Photo courtesy of U.S. ARMY CORPS OF
ENGINEERS |
| The Davis Pond diversion has been
beset with design flaws, which are supposed to be corrected
by year’s end. |
The ponding area is the 9,300-acre space south of the two-mile
long outflow channel that is bordered by a rock weir near Lake
Cataouatche. Vegetation had grown so much around the structure
— certainly a good sign considering the project's purpose — that
the water would not be able to flow properly. The settling of
the guide levee occurred much sooner than expected, and overflow
could have occurred. Vinyl sheet pile is being placed in the affected
areas.
Along with these technical difficulties, Villarubia says that
it was and will continue to be important to be sensitive to shrimpers
in the area expecting a good year, especially considering the
poor seasons of the past few years.
Helping preserve what is left of the Barataria Basin relative
to healthy marsh is the reason for the project, which is being
funded by the federal (75 percent) and state (25 percent) governments.
While the project is expected to preserve only 33,000 acres of
marsh with its introduction of nutrient-laden Mississippi River
water, it is expected to benefit 777,000 acres, roughly the land
area of the state of Rhode Island.
Consisting of four 14-foot square gated culverts, inflow and
outflow channels, east and west guide levees, and the rock weir
separating the ponding area and Lake Cataouatche, Davis Pond is
designed to pump upwards of 10,650 cubic feet per second (cfs)
of river water into the basin, ideally mimicking the floods that
refurbished the marsh prior to the Mississippi River being leveed
off.
The actual amount of diversion taking place is dependent on
the time of year and the salinity levels in the estuary. These
standards were set by the Davis Pond Advisory Committee, the group
in charge of governing how Davis Pond will be utilized.
By enriching the area in question, the state is protecting an
economic benefit of $15 million per year for fish and wildlife,
plus $300,000 for recreation, making it unquestionably one of
the areas most in need of attention. The intense tropical season
of 2002 accelerated the loss of land in the basin; many users
of the region fear what might happen if steps aren't taken to
stem the powers of nature.
 |
| Photo courtesy of U.S. ARMY CORPS OF
ENGINEERS |
| The Caernarvon diversion, designed
to funnel 8,000 cubic feet of river water per second into
dying marshes, has operated at 16 percent of capacity in its
first decade. |
“The past few years, we've really seen the loss of land increase,”
says Eric Muhoberac, owner of Louisiana Paradise Fishing Charters
and Guided Tours.
The similar diversion project in Caernarvon continues to do
well, according to Villarubia, even though it has averaged around
1,300 cfs for the 10 years it has been open. Constantly met with
opposition from commercial and recreational fishermen for its
outflow during certain times of the year, Villarubia says that
the project is pretty much going according to plan.
“Of course, we'd like to see what the effect would be on a consistently
higher flow, but we've also learned to be cognizant of the people
who depend on the marsh right now,” he said.
Studies have shown very positive marsh enhancement numbers, and
Villarubia said updated studies should be available soon. Soil
studies — what Villarubia calls biomass studies — from LSU and
the University of Louisiana at Lafayette have been as positive
as could have been hoped relative to the soil gained from the
river being able to support plant life.
But LSU researcher Rex Caffey said most of the alluviation in
the Caernarvon area occurred early on in the project’s history,
when it was operated at higher flow levels.
Smaller diversion projects near Myrtle Grove and West Pointe
a la Hache, operating since 1993 and which at full capacity divert
around 2,000 cfs, have been received with mostly positive analysis
thus far. These also are designed to help the fragile Barataria
basin.
Future projects, such as the one being planned near Head of
Passes that will divert river water into the West Bay area, are
in the feasibility study stages.
|