DEAD ZONES IN THE GULF AND GALVESTON BAY, NORTH AND SOUTH BACLIFF, SAN LEON, SHORELINE 77518
Low-oxygen area now deeper into Texas waters Largest-ever Gulf dead zone spans from Galveston to Mississippi River
By ERIC BERGER HOUSTON CHRONICLE Aug. 3, 2010, 10:37PM
The dead zone off the Texas coast is larger this year than scientists have ever measured, stretching offshore from the Mississippi River to Galveston Island.
An area of low-oxygen water that threatens marine life, the dead zone is at its largest during the summer months.
Scientists have surveyed the Gulf dead zone for a quarter-century, and this year's 7,722-square-mile area of hypoxic water is among the five largest.
"It's been getting larger and larger over the last five to seven years," said Nancy Rabelais, a Louisiana scientist who leads efforts to annually map the dead zone. "As it's been getting larger, it's expanded farther into Texas waters.
"This is the largest such area off the upper Texas coast that we have found since we began this work in 1985."
Discharge from the Mississippi River, which carries nitrogen and phosphorous nutrients from Midwestern states, largely creates the dead zone.
These nutrients, partly from commercial fertilizers, spur the growth of algaeblooms which, after dying, sink to the bottom. There the bacteria which feast upon the algae also bloom, depleting oxygen in the water.
Fish and shellfish often can swim away from these areas but immobile organisms, such as clams, simply die without access to oxygen.
Scientists are beginning to try and quantify the economic effect of dead zones, primarily due to potential disruption of fisheries.
"There are a whole host of biological consequences for fish in hypoxic areas, and when you add up all those different things you might expect there will be less fish to catch," said Martin Smith, an environmental economist at Duke University.
In recent years Smith has studied the effects of hypoxia on North Carolina fisheries at the mouth of the Neuse River, and he said low-oxygen water may have reduced catches by 10 to 15 percent.
Long-term worries Smith is part of a team that recently received a four-year, $700,000 grant to perform the first extensive study of the economic consequences of the Gulf dead zone.
In the short term it may benefit some fisheries, he said, because some species such as shrimp may be more tightly clustered at the edge of hypoxic areas, making them easier to catch.
Nevertheless there are long-term concerns about areas of low-oxygen water because they may reduce the reproduction of fish, or slow their growth rates.
"One would expect that if there's less dissolved oxygen, as the severity of the problem worsens, the consequences are going to get worse, too," he said. "But we're not going to answer that question scientifically until we do the study."
Common in summer Texas has seen dead zones before. Excessive rainfall in 2007 caused the Brazos River to discharge more than twice as much water into the Gulf of Mexico than previously measured since at least 1967.
This large amount of fresh water carrying nitrates led to the creation of a temporary 1,750-square-mile area of oxygen-depleted water, stretching from Freeport to Matagorda Bay.
And the Gulf's summer dead zone — such areas occur most commonly in the summer when winds are lightest - has stretched along the upper Texas coast before.
Now it appears that, absent tropical weather in the summer to break up dead zones by mixing the water, dead zones will become permanent summertime fixtures.
"There's still room for it to grow," Rabelais said. "It just has to do with the pressure of more people and nutrients. It means lower water quality, and larger algae blooms. It's certainly not a good thing."
eric.berger@chron.com
Subject: deadzone reply tss
WE have a dead zone right here in Bacliff Texas, on Galveston Bay, caused by ZERO oxygen level towards the bottom, flowing out of the Reliant spillway park, due to treated sewer being dumped into the discharge canal. you can see the pipe from google search. i was told by TPWD, from that pipe down to the mouth of the bay, via the discharge pipe, there is a blue green algae that has created the ZERO oxygen levels towards the bottom. the ZERO oxygen levels once the water discharges into the bay, runs both North and South up and down Bacliff, and San Leon shore line. Both FLOUNDER AND STINGRAYS have been seen floating belly up in large numbers. this has been going on for about 4 or 5 years, every year about this same time we saw it this year, and is generally seen around no tide movement days. BUT, we have had a significant reduction in the numbers of flounders in our area over this same time frame. i guess that's why we smell fece's in Galveston bay from time to time also. isn't progress wonderful. ...not///
check out the next addition of the SEABREEZE newspaper.
stupid is, as stupid does, and sometimes, you just can't fix stupid...
please see article ;
August 6, 2010
GOT FLOUNDER? Not in San Leon...
GOT FLOUNDER? Not in San Leon...
Got Flounder? Not in San Leon.
During the month of July, flounder and stingray have been floating up dead all along the San Leon/Bacliff shoreline on the north side. Our freelance reporter, Terry Singeltary, ob- served dead flounder floating by in groups of twos and three's with an occasional five or six. These are big, mature flounder, from two to seven pounds. Along with these flounder, dead stingrays have been seen floating by. Mr. Bobby Redfield, who lives on Bayshore Drive, also observed the same thing and gave me a call. This went on for several days. We received eight more calls where someone people left messages regarding dead flounder floating around the spillway, but did not leave their names and numbers. Our reporter contacted Lance Robinson, the Texas Parks and Wildlife Biologist located at the Dickinson office and expressed his concern about the destruction of these fish. Mr. Robinson said that they were aware of this problem and knew the cause. It turns out that a water treatment plant in the Bacliff area has a discharge pipeline that dumps into the HL&P outlet canal and goes out by way of the spillway and follows the tide. Since there is no longer any pressured flow discharging from HL&P, the chemicals from this treated water build up, removing all of the oxygen from the bottom of the water along the shoreline. The fish that live on the bottom of the bay, like flounder and stingray, cannot survive. This has been going on for years and has not been addressed. With the three sewer plants dumping into Dickinson Bayou and the de- pletion of flounder it makes you wonder why anyone in their right mind would want to put another sewer plant dumping into our precious, fragile resources. Mr. Robinson said they were having a meeting on this very subject. The meeting was to take place one week ago from this newspaper printing. Our reporter has put a call in to Mr. Robinson three days prior to this publication and at this time has not been called back. Maybe the Texas Parks and Wildlife has to contact the CCA and ask them how they should handle it. As we know more, you will know more. Do you fisherman ever wonder why there may be a shortage of flounder? With all of the sewer plants up and down the Texas coast dumping water treatment chemicals into our bays, creeks, rivers, bayous, estuaries, it's no wonder that the flounder are disappearing. What are you going to do about it Texas Parks & Wildlife? Are you going to keep cutting back the limits with the fisherman until you stop fishing for flounder forever, or are you actually going to address the problem? It's time for you Texas fishermen to wake up and let your voices be heard.
http://seabreezenews.com/issue/Page_16.pdf
TSS
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