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intense, so that much of our rainfall will be downpours as opposed to smaller events spread over a few weeks. Already, Burns and his team found that the Catskills are getting wetter as it warms. “What we found in our study is not what we actually thought we would find. The amount of precipitation has increased since the 1950s, quite a bit, on the order of 5½ inches.” With increasing development, intense storms mean amplified flooding as the water runs off impermeable surfaces. These paved roads, which don’t absorb rainwater or overflow from the river and tributaries challenge places like the Strand in Kingston.The Hudson River Maritime Museum, on the banks of the Rondout Creek, is already considering creating an off-site for their nonexhibited collections and other emergency plans. Many attribute weather extremes all over the country to the increase in temperature, with Hurricane Katrina being the obvious example. But in recent spring seasons, storm discharges are becoming taxing locally. In 2005, it was reported that Ulster and Green counties received between two and just over five inches of rain over one weekend in April. The Wallkill River and Esopus Creeks flooded, causing roadways and bridges to be shut down for days. Waters from the Rondout Creek rose so quickly in Kerhonkson that 27 homes were inundated and Federal Emergency Management Agency had to offer aid. In 2007, Ellenville reported receiving just about 5.6 inches, while Saugerties received 6.77 in the span of one day. Many townships declared states of emergency and schools in the Kingston, Onteora, Rhinebeck, and Pine Plains districts closed. The Northeast Climate Impact Assessment defines the 100-year floodplain as “the maximum flood elevation likely to be equaled or exceeded on average once every century in a given location. In any one year, there’s a one percent probability that a 100-year flood will occur.” However, many towns in 100-year floodplains in the Valley are already experiencing unprecedented amounts of flooding, and the number of spring precipitation events being called “major storms” is becoming common, with consequences to the power grids, drinking water and people in need of emergency rescue. Because precipitation is coming now in short spurts, there is also the danger of intermittent stretches of drought. “We know that in a warmer world, the droughts will be more severe because warming enhances evaporation and transpiration,” Burns said. Because it’s an estuary, when the flow coming out of the Hudson gets low, as it does in the summer, the saltwater migrates up. This salt front, defined as 100 mg/L chloride concentration, is very sensitive to sea level and also to drought. While the position of the salt front also moves with the tides and, in fact, is furthest upstream when there is a full moon or high tide, one concern with climate change and the predictions about sea level rise is that this would tend to push the salt front even further upstream. The concern is for those cities and towns that draw drinking water from the Hudson. Paul Lill, Plant Administrator at Poughkeepsie’s Water Treatment Facility, said that when the salt level rises, they adjust their schedule to pump only during high tides, when the river runs south and salt is less concentrated. The facility has the capacity to pump 19 million gallons per day but generally only uses 10 million. So they can pump at a high rate at high tide, and at a low rate, or not at all, at low tide, when the salt concentration is at its highest. That was their strategy during recent droughts. In 2001, because of the drought’s severity, the Army Corps of Engineers agreed to release water from the Sacandaga Reservoir in the Adirondacks into the river, freshening the saltwater they pumped. Newburgh is the southernmost community to pull water from the Hudson. Others include Highland, Hyde Park, Port Ewen, and several farther upstream. Lill said that in the short term, Poughkeepsie isn’t worried about drought. In the long term a desalination plant, though it’s not something they’re planning, is in the back of their minds. He estimated it would be a $50 million project, just to get the equipment, site planning, and engineering set up, exclusive of operating costs. ENVIRONMENT, DISRUPTED John Cronin, Director and CEO of The Beacon Institute, said that the location of the salt front is critical because, from an ecological point of view, the salinity of the water will have a more dramatic effect than other factors on the Hudson River’s marshes and wildlife. Right now, the Beacon Institute is in the development stages of a monitoring system that will document changes in the

river due to sea level rise. As part of their Rivers and Estuaries Observatory Network, remote sensing technology will be deployed to create an interconnected network that will extend throughout the river. A fundamental part of their monitoring will be fresh water salinity, river level, river current, and other physical and chemical changes over time. Cronin said, “The Hudson’s tidal, so sea level rise is going to have a dramatic effect on the shoreline, the physical characteristics, and the ecosystem itself. There will be a displacement of habitat and altering of animal behavior.” A fish accustomed to particular water salinity and temperature may find itself dramatically affected by alterations. In order for the negative affects on river biology to be mitigated, human impacts will have to be managed more carefully. Cronin said that it’s premature to draw conclusions about the effects of climate change on the Hudson River. While he can’t reliably say it’s because of global warming, he noted that there has been infrequent icing of the river, once a reliable characteristic. “It’s important to remember,” Cronin said, “that ice serves a function in the river. It is not just the cold state of water.” River ice plays an important role in the chemistry and ecosystem sense; It cleans out detritus and brings nutrition to the fish. It serves to scour and clean marshland, and ice melt and retention on land is important to the hydrologic cycle. With a focus on its tidal wetlands and sub aquatic vegetation beds, Betsy Blair, the Regional Marine Habitat Manager for the Hudson River Estuarine Research Reserve, an arm of the Department of Environmental Conervation, identified the biggest concern in the face of climate change to be the potential to lose the vital natural communities that exist along the Hudson River. “Our place within the DEC is really being stewards of the Hudson River’s aquatic habitats. I see a very real threat.” With hard engineering (structures like steel sheet piles, concrete slabs, and timber cribs—basically, containers filled with rocks) along 41 percent of the Hudson River’s shoreline, the marshes are becoming less able to keep pace with rising tides. As the wave energy hits the sediment beds, then bounces off these hard elements and washes over the beds again with increasing force, erosion is compounded. Tidal marshes are extremely important ecologically: to fish for spawning, nurseries, and foraging habitat; to birds for breeding and nesting; to the river’s health by pumping oxygen back in and removing sediments; as well as to us in sequestering carbon and protecting the shorelines from erosion. Blair worried, “The sea level rise estimates are, if we actually reduce carbon dioxide emissions, maybe 4 to 21 inches. If we do business as usual, the estimates are something like 8 to 33 inches. So it really depends on where we fall into that range.” With invasive species like Zebra Mussels stripping the water of algae, microscopic plants and animals, and even dead plant material, the river’s whole food web and oxygenation is based on what’s being produced right now in the wetlands and in submerged aquatic vegetation beds. One of the things the Research Reserve is working on is to look at shorelines and strategize what can be done to mitigate the erosion that’s going to be associated with sea level rise, and preserve these important natural communities. Aside from preserving land (a key component in addressing climate change), Scenic Hudson works with various interests to encourage responsible development that avoids the compounding dilemmas created by urban sprawl. It frequently assists with cutting-edge projects that reflect the new markets that environmental stewardship represents, such as the goal to make Stewart the first carbon-negative airport in the country and to build a stateof-the-art green hotel in Beacon. Historically, Scenic Hudson’s top criteria was connecting people with the river. So any waterfront property was an acquisition priority for parkland. “In view of curren t and anticipated rises in sea level and temperature,” said its president, Ned Sullivan, “we are adjusting our land acquisition strategy. We are buying more upland property that will be safe from innundation and will allow wildlife and vegetation to migrate above new tidal levels.” Scenic Hudson still sees the ecological value and potential for that land to serve as a bridge for the migration of aquatic species, but those spots with picnic tables or benches on them might become a place to support subaquatic vegetation instead of human recreation. “One idea that we put forward,” Sullivan said, “is to create climate change zones. Let’s identify the things in our community that are going to be affected by rising tides and increased storm surges, and make ecological preserves there. So as the tide rises, there could be a place where that could happen, and we wouldn’t lose money because homes were swept away.” 4/08 CHRONOGRAM COMMUNITY NOTEBOOK 35

Chronogram - April 2008  

A regional magazine dedicated to stimulating and supporting the creative and cultural life of New York's beautiful Hudson Valley. - April 20...

Chronogram - April 2008  

A regional magazine dedicated to stimulating and supporting the creative and cultural life of New York's beautiful Hudson Valley. - April 20...

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