Mon 5 Mar 2012
Although the Delaware River has always had a long history of flooding, the ever increasing population of people living, working, and travelling on its adjacent watersheds has significantly altered the hydraulics of the tributaries and the floodplain itself. While it is absolutely essential to decrease development in this unprecedented time of increased precipitation and rising sea levels, it is also crucial to carefully assess the potential consequences of our engineering proposals beforehand.
The New York State Department of Environmental Conservation, as reported by the Warren Reporter on April 8, 2011, stated: “New York City has agreed to modifications of releases of water from its reservoir system in the Catskill Mountains to better protect the ecology of the Delaware River in New Jersey and other downriver states, and help provide drought relief and flood protection.” The Express Times in Lehigh Valley, Pennsylvania had also quoted the NYSDEC on June 1, 2011, as contrarily admitting that “reservoirs, which spill into the Delaware River basin when they overflow, have the potential to exacerbate flooding downstream during major storms.”
The NYSDEC’s own website attempted to clarify: “While they are both dams, reservoirs are not flood control dams. Whereas flood control dams are specially designed to remain largely empty to capture major runoff events, reservoirs are designed to remain largely full, reserving water for later uses. However, reservoirs can and do provide some flood protection benefits, because even when full, they reduce downstream peak flow rates during large runoff events.” This assertion might not be true if the reservoirs overflowed beyond their capacity for intentional or unintentional relief from a major storm event.
Organizing a public educational workshop about the risks of building large engineering structures which not only protect, but allow increased development in fragile riparian areas prone to flooding would be a step in the right direction. The Delaware River could be explored from its head in New York State, down past Trenton and Philadelphia and into the Delaware Bay Estuary where it meets the sea. On a field trip, the workshop participants could observe how the land slopes steeply up from the river banks towards the towpath running alongside the Delaware Canal. They would see that while no longer used for mineral transport, the historically preserved waterway is now primarily maintained for flood water containment. Further south, as the land stretches gradually to level out to the shoreline, the workshop participants would see that boat houses close to the water’s edge on stalwart piers must rely eventually on the impermanence of saturated soil in which they are built. Standing as a grim reminder on the high banked roadway are twisted guardrails on their undermined foundations left washed away by recent flooding from hurricanes.
In another location down river, just across from Bowman’s Hill, one can walk in the soft saturated soil along the shoreline and observe uprooted and toppled trees leaning out over the water, while other trees stand just offshore with circular rivulets lapping up against their bending trunks. Plastic debris furling in the high branches again indicates the ominous water level reached by last year’s hurricanes. It soon becomes obvious that if one desires to live in the valley, it is most desirable to reside up in the high hill towns overlooking the river rather than down in the muddy floodplains, in dread of the inevitable rainstorms to come.
While living in view of a dramatic geological phenomenon such as the Delaware River is primarily one of choice to “live on the edge” in order to flourish in an environment of risk and potential change, a heightened awareness of how to build synchronously and sensitively with a potentially wild river becomes essential.