Written by Carol Frank Friday, 04 March 2011 00:00
Udalls Mill Pond has not been dredged in over 40 years. During those years, Udalls Pond, which is the ultimate repository for every drop of water than runs through the drainage system for the northern portion of the peninsula, has been filled with silt, sand and contaminants. The depth of the pond has been reduced to 1.5 feet in many areas. It has been choked with runoff and in spite of that, has served various functions for our community, that of floodwater control, a wildlife habitat and an aesthetic oasis.
Recently, Nassau County Legislator Judi Bosworth, held a public information meeting about the restoration of the area that has been designed and bonded through Nassau County in the capital projects plan and has met the strict permit requirements from the New York Department of Environmental Conservation. Legislator Bosworth said, “This important infrastructure work is a result of a bi-partisan effort that has been in the works for many years. The money for this is not coming out of the operating budget. It is bonded and while these are tough economic times, municipalities have an obligation and responsibility to maintain and improve the infrastructure of a community and protect the health of our environment.” She added that while the aesthetics of the pond will be greatly improved, the real reason for the $6 million project is to restore the pond’s capability to receive storm-water runoff, control flooding and to filter the water before it goes into Little Neck Bay and the Long Island Sound.
She introduced Brian Schneider, Nassau County Department of Public Works hydrogeologist and a certified professional in erosion and sediment control and Laura Schwanof, Vice-President of the environmental firm, EEC to explain the steps that lie ahead and to answer any environmental questions that might come up.
Mr. Schneider gave a quick lesson into what happens to a drop of water that hits, say, an impervious surface like Baker Hill Road. That drop joins other drops and flows into a catch basin and then into a series of underground pipes that go under Middle Neck Road and into an open channel or culver that parallels Old Mill Road and then turns right at Bayview Avenue. That water feeds into Udalls Pond. There are other entry points into the pond as well from the northern tip of the peninsula. A drop of water that falls on the ground may soak into the soil and eventually will make its way to the underground aquifer system. This process is referred to as “recharge.” However, if the soil is saturated or if rain falls faster than it can be absorbed into the soil, there may be overland runoff. All water flows, whether below ground or above, eventually end up in Udalls Mill Pond. This entire drainage system is called a watershed.
He also traced the history of the project that dates back to 2007 when Mayor Leonard Samansky filed an official request with the county to look into restoring the pond and the Grist Mill. It has taken years to get the green light for bonding, to fine tune a design plan and obtain the necessary permits, and while there may be refinements to the plan, essentially all systems are ready to go.
When the Saddle Rock Grist Mill was built sometime before 1700, a weir was constructed to impound the water and channel it through a race and feed it to the mill to turn the wheel and grind corn into flour. This weir, or dam, has become damaged over the years with a resulting lower water level in the pond. So, one of the features of the restoration will be to repair the weir, and raise its height some 5 inches. There will be a way for fish to swim back and forth between Little Neck Bay and the pond by constructing a fish ladder. This pass-through was one of the DEC’s requirements for approving the project. The design of the project will provide wetland nurseries for fish to spawn. It is hoped that a native fish, the alewife, which splits its life cycle between marine and freshwater habitats in impressive migrations will return to the pond to spawn.
Mr. Schneider viewed aerial photographs stretching back as many years as he could gather and learned that the eastern area of the pond was filled in with aquatic plants.
Currently, the pond is fringed with invasive plants, like the Phragmites australis, a marsh reed that spreads by underground rhizomes that are so thick and tough that they crowd out other plants. It has become ubiquitous in waterfront vistas and is an indicator of disturbed environments. The invasive plants will be dug up and native plants will be planted.
Native plants, appropriate to the conditions, are being selected not only to enhance the views of the flora for all seasons, but to provide seeds and berries for birds and other wildlife. While the list of plants to be used has not been completed, the following comprise the current list of plants to be installed:
Marsh Hibiscus, Groundsel bush, Seaside goldenrod, Pickerel weed, Cardinal Flower,
Northern Bayberry, Saltmarsh or smooth cordgrass, Buttonbush, Beach Plum and
Pasture Rose. One of the requirements for contractors who bid on the plant installation segment of the project will be a survival rate guarantee to ensure that the wetlands rehabilitation will be successful.
The most western side of the pond, beyond the bridge, will be dredged to 4’6” depth. An area closer to the bridge will be dredged to a 5’ 3” depth. On the portion of the pond just east and north of the bridge, the depth will be 8 feet. This deepest area will serve as a sedimentation basin which can be monitored for sedimentation levels and allow the county to clean it in the future at a far lesser cost.
According to Mr. Schneider, the dredging operation itself is quiet and not too exciting to watch. He says, “It just looks like a boat sitting on the water...but underneath, it has something like a ‘Hoover’ vacuum that churns the bottom and sucks up the water and sediment in a big hose that then gets pumped into a geo-tube.” The geo-tube looks like a big sausage casing, but its material is porous and will allow the water to drain out. This operation will take place on the Great Neck Park District property just north of the pond. After the geo-tubes have dried out, they are split open and the remaining solids are carted away. Mr. Schneider said that the most entertaining thing one might see in the dredging would be workers “dancing” on the top of the geo-tube to encourage draining. The DEC determines what kind of facility receives the dredged material depending on its level of contamination. Mr. Schneider reported that by borings taken, it has been determined that while the sediment to be dredged is contaminated, it is not hazardous.
Another part of the project is the installation of an elevated boardwalk that would extend into the pond parallel to the library’s rear parking lot. This is being done as an educational component so that people may view the pond and its wildlife more closely and learn about the watershed system. Again, the DEC was firm in requiring that any structure on the pond would not interfere with the light that penetrates the water; therefore, the boardwalk would not be made from wood, but would use a fiberglass reinforced polypropylene decking material, with the trade name ThruFlow, that is billed as having an anti-slip surface and as highly durable. It would be a light grey color to harmonize with the setting. The railings will consist of a woven wire mesh.
The project is to take place in stages. The DEC has stated that no work will be allowed to take place between April 1 and September 30 so that the nesting and spawning season would not be interrupted. Phase I, slated to begin in October of 2011 will include dredging on the east side and part of the west side of the pond as well as wetlands restoration and the beginning of the boardwalk work. Phase II will consist of finishing the dredging, repairing the weir, installing the fish ladder and finishing all other components.
A number of residents attended the meeting, mostly neighbors who border the pond and many had questions about the dredging process and the extent of the rehabilitation of the area.
Concerns were raised about the boardwalk. Some neighbors feared that it would be unsightly, draw crowds of people, encourage students to throw things into the pond and so forth. Others questioned the county’s ability to take on the responsibility of caring for a park, emptying trash cans and picking up trash. Questions were raised about the role of the library in providing access to the boardwalk.
Mr. Schneider in an email after the meeting said that the county was looking into addressing the concerns raised at the meeting and was considering bringing the boardwalk closer to the shoreline, installing gated access that could be locked and providing solar powered trash cans that compact trash and require less maintenance. Legislator Bosworth urged residents who have questions or concerns about any aspect of the project to call her office directly.
Although Mr. Schneider said that calls to the library’s attorney had been made regarding an easement to the shoreline, Legislator Bosworth has initiated a meeting with library representatives to discuss any issues in depth.
(Editor’s note: While researching this article, we found many references to Udalls Pond without an apostrophe and many that added it. We have been guilty of the latter. Historically, it was named Udalls Pond and we choose to honor its early spelling, therefore, we will omit the apostrophe from this point forward. The US Geological Survey also uses the original spelling. - CF)