The healthiest long-term shad stock in the Bay watershed could be jeopardized if a water intake is built in the Mattaponi River to supply water for a controversial new reservoir, according to a new scientific review.
The Virginia Institute of Marine Science warned of the “potential for significant adverse impacts” posed by the intake, which would supply water to Newport News’ long-planned King William Reservoir.
The scientists said the Mattaponi is the most important shad spawning and nursery area for the York River, which has maintained the Bay’s healthiest—though still depleted—shad population over the decades. As a result, “we do not recommend placement [of the intake] in the Mattaponi River,” they said in a letter to the Virginia Marine Resources Commission, which has scheduled a hearing on the issue April 22.
The objection by VIMS scientists, who provide scientific advice to the commission, is the latest hurdle for the 1,500-acre reservoir which has been sought by Newport News for more than a decade to shore up its drinking water supply.
The city plans to build a 78-foot-high, 1,700-foot-long earthen dam on Cohoke Creek, a tributary of the Pamunkey River, and fill it with water withdrawn from the adjacent Mattaponi River. (The Mattaponi and Pamunkey join downstream to form the York River.)
Newport News Waterworks provides water to 400,000 customers and projects to be serving at least 600,000 by midcentury, but says it will be facing shortages as soon as 2015 unless the reservoir is built.
Even before the VIMS letter, the proposed reservoir had become one of the most controversial projects in the Bay watershed. If approved, it would lead to the loss of more than 430 acres of wetlands, which would be the largest loss allowed by regulatory agencies in the region since the Clean Water Act was passed in 1972.
Citing a host of concerns, the Norfolk District of the Army Corps of Engineers, which ultimately must approve the project, rejected a permit application by the city of Newport News two years ago, saying “it is not reasonable to build such an environmentally damaging project to satisfy a need that may never materialize.”
That decision was challenged by then-Gov. Jim Gilmore who, during the last days of his administration, invoked the rarely used authority of a governor to challenge the decision of a Corps’ District.
That sent the issue to the Corps’ North Atlantic Division in New York, which ruled last fall that the reservoir proposal was “the least damaging practicable alternative” to meet the long-term needs of the Newport News area.
But the North Atlantic Division said the Corps’ approval depended on Newport News’ first securing needed permits from the state, the completion of an updated wetland mitigation plan, and the resolution of issues about the project’s impact on Native American sites. Also, the state must determine the project is in compliance with its federally required Coastal Zone Management Act program, which seeks to protect coastal water bodies.
Approval by the VMRC, which has to issue a permit for the water intake, is the first of those remaining hurdles for the project.
VIMS put together a special team of scientists to review the potential impacts of the intake and concluded that it posed a threat to American shad, as well as a number of more poorly studied fish including blueback herring, alewife, and white and yellow perch.
Shad, once the most valuable commercial species in the Bay, have been depleted to the point that the entire Chesapeake is now closed to shad fishing. They are an anadromous species, spending most of their life along the Atlantic Coast, but returning to their native river to spawn.
Although still below historic levels, the York River has maintained the healthiest shad population of any Bay tributary. Its shad population is primarily driven by the highly productive spawning and nursery grounds in the Mattaponi, according to VIMS scientists.
They noted that the Bay Program’s Chesapeake 2000 agreement, and the Atlantic States Marine Fisheries Commission, have placed a high emphasis on restoring shad populations.
The ASMFC, a compact of all East Coast states that is responsible for managing migratory fish, in 1999 approved a phaseout of all ocean fishing for shad as a means to help rebuild depleted populations in coastal spawning rivers. Its shad management plan recommends that states take actions to “ensure that water withdrawal (e.g., cooling water, drinking water) effects … do not affect alosine stocks to the extent that they result in stock declines.”
The scientists said the intake pipe, to be built in a 400-foot-wide section of the tidal river, would pose a threat to egg and larval stages of shad. As the river ebbs and flows with the tide, they said, the free-floating eggs, as well as the early life stages of fish, would be repeatedly exposed to the intake.
VIMS estimated that this could lead to the loss of 6,802 shad larvae and 795 shad eggs daily. Losses to other species, such as white perch larvae, could be much greater. Also, because fish are known to be attracted to structures in the water column, eggs and larvae—which are an important food source for many fish—may suffer increased predation.
Given that a female shad can produce hundreds of thousands of eggs, the VIMS scientists acknowledged that the projected losses appeared relatively modest and said they could not predict the impact on adult populations.
But they cautioned that the withdrawals added yet another source of stress to an already depressed stock, and could threaten its recovery.
“It is widely held that subtle changes in rates of mortality of fish eggs and larvae can produce large fluctuations in recruitment to adult stocks,” the scientists wrote. “It is also known that low recruitment is generally associated with stocks that are low in abundance while stocks that are higher in abundance produce more offspring. Thus, small increases in daily mortality of eggs and larvae of stocks that are low in abundance could result in recruitment failure.”
Further, the scientists said the intake issue should not be considered in isolation because other land-use changes within the watershed “will undoubtedly supply additional stress to adjacent aquatic resources.”
Their report suggested that any decision on the permit be delayed until a comprehensive regional water allocation strategy was developed. Without such a strategy, the scientists said, the commission and the Bay community would be faced with further disputes between large-scale economic and environmental issues in the future, and without adequate information.
If the permit cannot be delayed and the intake has to stay within the York watershed, the scientists said it should be moved to the Pamunkey River, because it would likely have less of an adverse impact on shad stocks, although it may still add to cumulative ecological stress on the river.
If the intake is approved, that scientists said several caveats should be made. Spring withdrawals should be reduced to minimize impacts on fish, the report said, and monitoring programs be stepped up to measure the impacts on fish populations and the local environment.
The VIMS report adds fuel to what was already shaping up to be an Earth Day showdown before the VMRC, which has scheduled hearings throughout the afternoon and evening to hear from critics and supporters of the reservoir.
“It’s pretty damning,” said Roy Hoagland, Virginia director of the Chesapeake Bay Foundation, said of the VIMS report. “It shows the seriousness of the potential impacts to the shad fishery. It provides confirmation to what a lot of people have said about the risks of that intake structure. It puts a tremendous amount of pressure on VMRC to do the right thing and deny the permit.”
Billy Mills, former executive director of the Mattaponi and Pamunkey Rivers Association, said “it would be irresponsible with this level of report, to suggest that any effort at mitigation could make up for the adverse impacts. This report says to me, ‘Hands off the Mattaponi if we’re serious about restoring the Bay’s shad fishery.’”
But David Morris, planning and program manger for the Newport News Waterworks, disputed that the intake would have a major impact. He said plans already called for reducing withdrawals during sensitive periods.
“Obviously, an intake is going to have some effect, but how significant is it?” Morris asked. “We’ve been saying for a dozen years that it is a very small effect. VIMS is saying any effect is unacceptable. But there are a whole lot of effects going on that they didn’t account for. One of the concerns that we have is that they didn’t seem to be able to put [impacts] into an adult fish perspective.”
He said modeling efforts examining impacts on eggs and larval fish suggested the project would have little impact on the number of adults. Morris rejected the suggestion of moving the intake to the Pamunkey—which could take years of additional study—saying that “isn’t an option.”
Gov. Mark Warner has not taken a public position on the project, saying he wanted agency officials to review the proposal and make a decision. Secretary of Natural Resources Tayloe Murphy said the VIMS report has not changed the governor’s stance.
“What the governor has said was that he would like the process to be handled by the professionals in the agencies,” Murphy said. “The issue before the marine resources commission will be handled by the commission. They will take into consideration the report that VIMS has prepared.”
More about the American Shad
The American shad, Alosa sapidissima, is the best-known of the six species of shad and herring that swim in the Chesapeake Bay.
It is a handsome fish, with a metallic blue-green back that lightens to silver along its sides and a black spot at the shoulder, with several smaller spots trailing behind.
The American shad can reach a length of 30 inches, and is the largest –and considered the most delicious to eat–of all the shads.
The anadromous American shad is indigenous to the Atlantic coast from the St. Lawrence River to Florida, and spends most of its life at sea in large schools. It returns to the freshwater river in which it was hatched to spawn.
As the shad migrates from saltwater to fresh, its cloak of large, easily-shed scales dulls from blue-green to brown. They enter Chesapeake Bay from January to June between the ages of four and six, spawning in freshwater to low-salinity tributaries as far north as the Susquehanna River.
Shad undertake extensive ocean migrations: During an average life span of five years at sea, the American shad may migrate more than 12,000 miles.
— Source: Chesapeake Bay Program