Quin Hillyer, Wall Street Journal
Published: Dec. 25, 2015
undisturbed cypress swamp, nourished for centuries by Mississippi River
sediment. But decades of logging and development (thereąs a large levee on
the other side of Jesuit Bend protecting it from the river) have eroded
and starved the wetlands, creating a pond or lagoon of open water 3 to 4
feet deep.
This is a microcosm of the problem threatening the whole Louisiana
coastline. When wetlands turn into open water, the loss of grasses and
nutrient-rich soil eliminates prime areas for breeding, spawning and
feeding some 16% of the entire nationąs fisheries, along with winter homes
for millions of waterfowl, and habitat for dozens of land animals such as
beaver, mink and otter.
The state of Louisiana, with some‹but far less than expected‹federal help,
has been trying to stem (and eventually reverse) this tide for a
quarter-century. Yet successes have been fleeting. Just to retard erosion
is a difficult, expensive engineering feat; actually restoring marshland
is tougher still. Long-standing government projects like the Caernarvon
and Davis Pond freshwater diversions are mildly successful but took more
than a decade to complete. And because they move water but very little
sediment from the Mississippi to the targeted area, their overall benefits
are increasingly in question.
Several private companies have dredged sediment from brackish areas to
create new wetlands in their immediate vicinity, also financing it (but
not necessarily in advance) with sales of mitigation credits. But this is
just rearranging sediment thatąs already there. The Jesuit Bend project,
by contrast, pipes in the nutrient-rich, freshwater sediment flowing from
the entire Mississippi River basin. This is the sediment that would
naturally replenish the marsh were it not for the man-made levee system
that protects homes and river commerce.
łItąs good to get it out of the river, rather than an adjacent lake
bottom, where you are basically robbing sediments from Peter to pay Paul,˛
says Paul Kemp, a professor of Oceanography and Coastal Sciences at
Louisiana State University and an often-cited expert on wetlands issues.
łAnd the river is probably a cleaner source of material than, say,
offshore dredging, because it doesnąt have all the salts the offshore
sediment does.˛
The Jesuit Bend project used 30-inch pipe to transfer 1.3 million cubic
yards of Mississippi River sediment 5 miles downriver, underneath a state
highway and railroad, and thence into the open-water lagoon.
I canąt vouch for the arithmetic, but Restoration System says that if the
sediment were loaded onto a football field, the mud would be taller than
the Washington Monument.
The project required nearly five years of permit acquisition and
engineering planning, but the actual pumping was accomplished from
mid-October through the end of November. The 3-foot-deep lagoon has become
nutrient-rich land 4 to 8 inches above the waterline, and 211,000
individual plantings of various marsh grasses are now being affixed by
hand.
The entire site should be a thriving, moist-green ecosystem by spring, and
perhaps, if fortune smiles, the 43 remaining acres of adjoining cypress
will seed and begin expanding. Restoration Systems says upkeep is funded
for 50 years, and the site will be protected forever by a conservation
easement.
A Nov. 12 survey reported 44 species of birds, including four bald eagles,
125 snowy egrets, 30 great egrets and five great blue herons. On my Dec. 7
visit, one particular bald eagle was alternately perching, swooping and
soaring; a 4-foot gator meandered down a canal; a bull redfish thrashed in
the shallows; and a dozen workers in hip boots laid down, about every 10
feet, grass plant after grass plant into holes they had punched in the
new, wet soil. Clearly, this isnąt a dredge-and-leave job.
Published reports indicate that the Jesuit Bend project will cost about
$20 million, or roughly $60,000 to $70,000 per acre: significantly lower,
by five figures, than apparently similar public projects. Cost comparisons
for wetlands restoration are notoriously difficult, because the underlying
topographies, and thus the technological needs of the projects, may vary
widely. Nonetheless, the lesson in all this is that private incentives
work.
łIt is really good to find private investors who are able to do some
effective kinds of restoration,˛ says Mr. Kemp, the LSU professor. łThe
emergence of a market, which has always been a hard thing to predict, is
really good news.
Mr. Hillyer is writer and Louisiana native now living in Mobile, Ala.