Water recirculation helps Texas shrimp farms comply with state regulations

Waste Not, Want Not

Residents concerned with effluent produced from shrimp farms

By MELISSA McEVER
The Brownsville Herald

ARROYO CITY, Texas — The yearly harvest is complete at one of the ponds owned by Arroyo Aquaculture Association.
On the harvest’s last day, a pungent odor filled the air as an 18-inch pipe drew water from a pond and yielded the crop in question — 14,000 pounds of Pacific white shrimp. A machine then poured the shrimp on ice, keeping them fresh for market. In total, the association, a co-op of about 20 farmers, has produced about 800,000 pounds of shrimp this year to be sold to supermarkets and wholesalers.
The water left over, laden with waste products, will be left to settle for a few weeks or longer until the pollutants settle to the bottom or are digested by algae. This year, the farm took in about 200 million gallons of water from the Arroyo Colorado, and probably will return significantly less than that to the fragile tributary, said farm manager Stephen Kou.
Arroyo Aquaculture’s Texas Commission on Environmental Quality permit, which is up for renewal this year, strictly limits the amount of effluent that can be discharged and the pollutants it can contain. That’s a big change from about a decade ago, when shrimp farms were subject to few regulations, Kou said.
“We’ve improved drastically, but most people don’t realize that,” he said.
Environmental groups once considered the Texas coasts’ shrimp farms a menace to the state’s fragile tributaries and its wild-shrimp industry. But that was then. Today, the shrimp-farm industry is more tightly controlled, and many groups say they are pleased with the way it now handles its wastewater discharge, as well as the threat of shrimp diseases.
“We think they’ve done a very good job,” said Pam Baker, fisheries biologist for Environmental Defense. “The amount of water discharged has been reduced tremendously — it once carried so much sediment, waste, feces, feed. They’ve much improved their practices.”
The Rio Grande Valley has four shrimp farms that discharge into its waterways. Two have permits to release wastewater — water left over after the shrimp are harvested — into the Arroyo Colorado, and two are permitted to release wastewater into the Laguna Madre. Both water bodies are environmentally sensitive, but the Arroyo is especially vulnerable because some parts aren’t in compliance with the Clean Water Act.
Despite the vote of confidence from environmental groups, some residents are concerned about the impact of amendments being proposed to Arroyo Aquaculture Association’s wastewater permit this month. The association has a wastewater permit allowing its ponds to discharge a maximum of 1 million gallons per day. The farmers are asking to be allowed to discharge into the Arroyo from January to March, which the permit currently forbids. The permit application also requests a reduction of sampling frequency.
“That bothers me more than anything else,” Paul Bergh of the Coalition to Save the Arroyo Colorado said of the sampling changes. The coalition was formed in the 1990s to protest the once-lax rules for shrimp farms.
Another shrimp farm on the Arroyo, Southern Star, is seeking a renewal to its TCEQ permit, but isn’t requesting any amendments. The permit allows the farm to discharge up to 60 million gallons per day. Bergh, who lives in Arroyo City, said that the city’s residents are concerned that the effluent is harming the arroyo.
“They’re (residents) seeing dirty water and foam, and they’re upset,” he said.
Arroyo Aquaculture Association requested changes to its permit so the farm can more easily comply with state regulations, Kou countered. Back in the days of fewer restrictions, the farm discharged effluent year round, and so officials banned discharging between January to March to give the Arroyo a rest, said an official from the Texas Parks and Wildlife Department. Now, the farm discharges only for about 10 days at the end of the season, Kou said. The season usually ends in September. Kou said the wastewater, which typically contains solid wastes, algae and ammonia, needs extra time to sit so the solids can settle and the algae can digest pollutants.
“It takes a few weeks or a couple of months,” he said. “So we’d like to discharge later (instead of in September).”
Because Arroyo Aquaculture and other shrimp farms now recirculate water through their systems and discharge less frequently, it also makes sense to reduce monitoring frequency, said David Buzan, coastal fisheries biologist for Texas Parks and Wildlife.
“The way it operates now, (farms will) bring water in and it might stay on the farm for more than a month,” Buzan said. “They don’t need to sample that same water over and over” — only when the farm is preparing to release it into the waterway, he said.
Arroyo Aquaculture’s farmers, as well as other shrimp farmers in the region, are struggling to keep up with strict environmental regulations and still keep their businesses afloat, they say. In recent years, the farmers have faced stiff competition from overseas producers, who aren’t subject to the same rules.
“It puts us at a disadvantage,” said Fritz Jaenike, general manager for Harlingen Shrimp Farms, based in Los Fresnos. “So we’re trying to find customers who want to buy shrimp grown to certain standards.”
Because of pressure from foreign competitors, farmed-shrimp prices have hit rock bottom, Jaenike said. Harlingen Shrimp Farms, Arroyo Aquaculture and other farmers have cut down on production. A few have even sat out this season, Kou said.
Some advocates are concerned that these financial pressures could cause farms to be less than honest in monitoring their effluent. Depending on the terms of a permit, shrimp farms must self-monitor their discharge for pollutants regularly and submit reports to TCEQ. If found to be out of compliance, farms could face stiff penalties.
“It’s like the fox guarding the henhouse,” Bergh said. “Do you think they’re always going to report a violation, especially when it comes with a fine?”
According to TCEQ records, Arroyo Aquaculture has been cited several times in the last decade for violations of permit parameters, but has only paid a fine once — $10,000 for major violations in 2006. Most of the other violations are minor to moderate, and were since resolved.
Other shrimp farms in the region have similar records with few fines. Southern Star, another shrimp farm in Arroyo City, paid $2,600 in 2005 for a violation, but the other violations were classified as “minor” and didn’t have fines attached, according to TCEQ records.
Occasional violations are to be expected, but hopefully they don’t point to a chronic problem, said Baker of Environmental Defense.
Although self-monitoring might seem to present a conflict of interest, TCEQ pays close attention to what the farms report, said spokeswoman Lisa Wheeler.
“We are very much involved when it comes to self-reporting,” Wheeler said.
Kou, of Arroyo Aquaculture Association, said that the farm is honest in its monitoring.
“If they find something wrong, we will accept punishment,” he said.
Buzan said that he thinks most shrimp farms are honest.
“Most do an effective job of monitoring … in general, I think the (monitoring) system works fairly well,” he said.
It’s not very time-consuming or difficult to keep up with water monitoring, said David Stephen, a consultant for Southern Star, the largest shrimp farm on the Arroyo Colorado.
“We monitor water quality every day and report to TCEQ monthly,” Stephen said.
What does take time — and money — is finding ways to clean the farms’ discharge water. Most farms keep the used water in settling basins for days or weeks until it’s ready to return to the arroyo or Laguna Madre without causing environmental disturbances, farmers said.
“It varies according to the water quality and the limits,” Jaenike of Harlingen Shrimp Farms said.
Farmers say they can’t afford to do much more. Bergh and other advocates for the Arroyo Colorado would like to see the farms construct wetlands to treat the water more efficiently, but that takes money and land — both of which are often in short supply for the average shrimp farmer.
“There’s not always land next door you can buy (for wetlands),” Jaenike said.
Kou said Arroyo Aquaculture farmers were interested in creating wetlands, but their space is limited. Because fewer farmers are harvesting shrimp, however, they could perhaps use production ponds for wetlands, he said.
Organizations like the Arroyo Colorado Watershed Partnership, a group of citizens developing a watershed-protection plan for the Arroyo, and the coalition might be able to help shrimp farms obtain grants to fund wetland creation, Bergh said.
Bergh said that he and other advocates don’t want to be confrontational with Arroyo Aquaculture or other shrimp farms. The farms have proven responsive to the public and to environmental concerns, he said, but there needs to be checks and balances in place.
“The answers are complex and not easy to come by,” Bergh said. “But we can find a way to make this work for everybody.”
The Texas Commission on Environmental Quality is accepting public comments on Arroyo Aquaculture Association’s wastewater permit amendments until Oct. 12. The document is on file at the Harlingen Public Library, 410 76 Drive. The agency also is accepting public comments on Southern Star’s permit renewal until Oct. 11. For more information or assistance, contact 1-800-687-4040.

Source:
The Brownsville Herald