Bay health shows little improvement

two reports say progress is slow

Wednesday, April 30, 2008

Also, the middle of the bay, which includes Southern Maryland’s section, is faring worse than the upper and lower portions of the bay, according to one of the reports, the Bay Health Report Card issued April 3 by the University of Maryland Center for Environmental Science.

The bay’s overall health did increase slightly in 2007, to C-, according to the UMCES report, but this improvement is considered a temporary result of last summer’s drought. The low summer rainfall reduced the amount of harmful nutrients and sediment reaching the bay.

The condition of the Patuxent River is particularly dismal; in a list of 14 assessed bay regions and tributaries, it shares the bottom ranking with the lower Western Shore, and earns a grade of D-. Concentrations of harmful algae were the highest ever recorded for the river; beds of aquatic grasses, which provide oxygen and habitat for other bay-dwellers, are continuing to disappear. For water clarity the river scores 5 percent, according to the report.

‘‘If you’re talking about the Patuxent, that is a bad-news story,” said Bill Dennison, vice president for science application at UMCES. ‘‘Bottom tier this year, in spite of so many years of good efforts.”

Even improvements in sewage treatment haven’t been enough to make improvements, he said.

‘‘The Western Branch [Wastewater Treatment Plant] is operating at really high capacity. They’re doing some of the best biological nutrient removal in the bay — world-class technology — and yet the Patuxent is still degrading. What’s happening is, we’ve addressed the point sources but we’re not addressing urban stormwater and agricultural runoff issues in addition. More, Calvert and St. Mary’s counties are just boom areas for urban and suburb development, and we’re just creating new ways to inject nutrients into the bay.”

With a D+ grade, the Potomac River scored somewhat better. The Potomac’s score showed a 4 percent improvement over last year while aquatic grasses continued to expand.

‘‘But water clarity remained very poor for the fifth year in a row,” the report said.

The upper bay’s outlook offers more reason for hope, making a better recovery than expected.

‘‘We didn’t expect the upper bay to be in such good shape,” Dennison said.

A drop in nutrient concentrations coming from the Susquehanna River and lagging development in the northern counties deserve some of the credit for the resurgence, he said. But nature is doing its part as well.

‘‘We had a resurgence in the aquatic grasses up there. This isn’t from restoration efforts, just a natural recovery,” he said. ‘‘These bay grasses are just thriving — dense, expansive beds. Water clarity has improved, reports that there’s more fish, waterfowl, crabs ... so the upper bay is showing some very good signs of improvement, but unfortunately it’s the isolated case, and overall the bay — and especially the suite of western shore tributaries — is degrading. One of the things to become quite apparent in looking at this over a 20-year period is [that] water clarity in the bay is degrading, more turbidity, and the truth is we don’t have a good answer for that.”

Even the upper bay’s resurgence may not be permanent; it is showing signs of deteriorating again. The influx of ocean water is mainly responsible for the relatively good condition of the lower bay, he said.

‘‘The solution to pollution is dilution,” Dennison said. ‘‘In terms of that lower bay situation, however, that said, in 2005 we had a big dieback of eelgrass down in the lower bay due to high temp events in late summer, and there’s a very slow recovery from that. With increased turbidity, those grasses are not doing well. That’s a key part of the equation.”

The rising sea level could also be disastrous for the bay.

‘‘I’m not arguing about climate change,” Dennison said. ‘‘The fact is, sea level is rising in the Chesapeake Bay. It has been for 100 years [according to measurements from tide gauges] ... and climate projections are for accelerated sea level rise, an ongoing problem that’s going to get worse.” Compounding the problem is that the land around the bay is slowly sinking because of the removal of groundwater.

In order to have any hope of saving the bay, ‘‘No 1 is controlling our growth. [There was an] 8 percent increase in population in a decade, a 42 [percent] increase in impervious surfaces, and that’s a frightening statistic. We’re making it so much more efficient to remove water from land, put it into the bay directly without filtering it through groundwater or through the forest grass, so I think that’s No 1.”

Also necessary is an increase in the use of agricultural best-management practices and a change in public attitude away from reliance on the government to solve the bay’s problems, he said.

These conclusions were reinforced by another report, the Chesapeake Bay Program’s ‘‘Chesapeake Bay 2007 Health and Restoration Assessment,” also released April 3.

Population growth in the bay’s watershed has negated most of the gains that conservation measures would otherwise have accomplished in the bay, the report said.

‘‘For more than 20 years, restoration efforts have managed to offset a variety of destructive environmental impacts, while making modest ecological gains in some areas,” the report said. ‘‘Recently this imbalance has intensified because of rapid population growth and land use conversion in parts of the watershed; thus major pollution reduction, habitat restoration, fisheries management and watershed protection actions taken to date have not yielded a significant bay ecosystem response.”

The recovery of the rockfish population following a fishing moratorium in the 1980s is one of bay restoration’s few success stories. But their population has been declining since 2003, according to data featured in the report.

The culprit for the decline could be a low population of menhaden, an important prey species for rockfish.

‘‘Basically, they’re still considered restored, but there’s some concern out there about the health,” said Chesapeake Bay Program spokeswoman Alicia Pimental. ‘‘ ... They’re considering that as a possibility, that a low menhaden stock means not enough” prey for the rockfish.

To combat this, conservationists are considering ‘‘ecosystem-based management plans” that seek to restore populations through monitoring their interactions with other species, rather than dealing with each species individually.

The rockfish are also facing a more outlandish threat— chemical contamination is apparently responsible for causing sexual abnormalities in male bass in the Potomac River. These chemicals, called endocrine disruptors, interfere with hormones; in this case, the male fish have had female eggs in their testes, according to the report.

The report also had grim news for urban pollution control. While agricultural and wastewater sediment and nutrient control programs have been making progress, control of nitrogen from urban and suburban areas has retreated 83 percent from the goal since accounting began in 1985, and phosphorus and sediment control have deteriorated almost as much.

With 130,000 people moving into the watershed every year, population growth plays a role in this problem, Pimental said, and addressing this might require growth control and lifestyle changes for those who already live there.

‘‘Basically, what we’re saying is the restriction of population growth and development. ... There’s lots being done out there, but with so many people moving in, and related development, it’s outpacing our efforts. There’s a lot of things people can do to help the bay in their own daily lives. It’s a little frustrating when people say there’s nothing I can do. I’m just one person but if people really banded together and made little changes — not fertilizing [yards] in the spring, or at all, not applying pesticides, driving less either by taking public transportation or carpooling with a co-worker — those are just little things people can do to make an impact. If more people started doing that, we might see a shift.”