319 Grant Projects Completed and Scheduled for work

319 Grant projects:

Here is a list of completed projects and on going  projects for the 319 Grant Funding:

Sears Park: two detention basins, one inground cistern and roof leaders,  BodPave pavor parking spaces and two Swales.

Wangonk South: Rip Rap Swale 

Wangonk North beach: Rip Rap swale and vegitative swale and establish grass on upper beach. 

Sears Place: Rip Rap Swale with check dams every 6 feet.

Seven Hills: Retrofit detention basin to collect more water and slow the flow of water transfering out of basin into storm drains. 

Sky Line Estates: establish rip rap swale leading from upper basin to lower basin, install filtrex sox to help filter out nutients prior to reaching lower basin. 

Mott Hill: Install cape cod style catch basin and 6" berm to direct water flow to basin that infiltrates into the ground at the top of Mott Hill prior to it reaching the lake. 

Clark Hill: Small detention basin designed for overlow from vegitatvie swale, discharge pipes in basin will redirect water to a lower storm drain holding tank where water is discharged into the ground.

Hawthorne: Catch basin insert ustilizing filtrex sox system to help filter nutrients from rain water run off of near by streets including route 66 and the Town hall location. This catch basin is the final stop before reaching the lake and has been identified as the final connector of several storm drains in the neigboring communities. 

Projects projected for the Fall of 2021 from 319 Grant Funding:

Bay Road:

Description of work:

Native wetland plants will be planted in and along both sides of the existing watercourse on the Middlesex Land Trust Property above the culvert on Bay Road.   The purpose of the additional planting is two-fold.   Increased plant cover on the ground surface will provide resistance to flow when runoff exceeds the capacity of the actual stream channel, thus allowing the velocity of the runoff to slow down and deposit sediments in the runoff.   Secondly, increased native wetland plants will uptake more of the soluble nutrients (phosphorous and nitrogen) found in the runoff.   An additional benefit is that the native wetland plants will provide a better habitat and not cause any restriction to the flow through the land trust property prior to going through the culvert under Bay Road.

Christopher Brook:

Description of work:

Christopher pond is a relatively shallow open waterbody where the water surface is controlled by a weir in the earth/stone dam located at the north end of the pond.   There are two culverts under Christopher Road which discharge into the pond.   There is currently a bypass channel located along the west side of the pond, which is separated from the actual pond edge by an earth berm roughly 4’ in width.   This bypass channel empties into the pond approximately 175’ north of the culverts.   The bypass channel appears to take all the flow from the western culvert under the road, while the runoff from the eastern culvert directly enters the pond closer to the east side of the pond.   There are several things to be done to Christopher Pond to improve the water quality which exits the pond and goes to the lake.   

The primary work is to cut off the bypass channel to allow all runoff to enter the main body of the lake with the sediment load which may be in the runoff to help make the pond shallower and allow it to become more of a wetland system than a pond.   As the pond becomes shallower with more vegetation, the ability to trap all types of pollutants found in the runoff will be greatly increased, thus reducing the pollutant load which will reach the lake from this system.

Brook at Edgemere Water Supply System:

Description of work:

Based upon several site inspections, the perennial stream is experiencing in channel erosion of the banks because of increased runoff volumes generated from the Sunrise Lane subdivision off Clark Hill Road whose stormwater basins discharge to the upper reaches of this stream system.   While the detention basins for the Sunrise Lane subdivision provide peak rate attenuation of runoff, there are significant increases in runoff volumes which are discharged from the subdivision for all rainfall events. 

It is well documented that increased runoff volumes discharged to receiving streams will have increased flow durations within the stream which cause erosion of the channel banks and the eroded material is carried downstream and deposited where the stream velocity slows down sufficiently to all the sediments to settle out.

It is also proposed to place a Filtrexx Soxx (12” or 18”) across the stream channel at two or three locations upstream of the culverts in an arc shape with the top of the arc facing upstream.  These Soxx will create very temporary ponding upstream of them (the Soxx are permeable) and will remove soluble nutrients from the streamflow.    Additionally, as the Soxx age, aquatic vegetation will become established within the matrix of the material in the Soxx.   They would not be removed from the stream channel but would be allowed to become part of the channel.  The Soxx will create several small step pools within what is currently a uniform sloped bottom of the stream.   These small pools will increase habitat within the stream channel.

As there are limited opportunities  to remove particulate and soluble nutrients in the conventional stormwater management systems located on the many roads around the lake, this location provides an easily accessible and appropriate location to trap some of the nutrients and prevent them from reaching the lake.

The area upstream of the culverts is densely wooded.   There are some shrub species along the banks, but for the most part, there is no ground level vegetation along edge of the stream banks.  To improve the stability of the channel banks approximately 100’ above the culverts, it is proposed to cut back some of the shrub vegetation by hand which overhang the stream (this will not reduce shading of the stream as the overhead tree canopy remains in place) as the branches which overhang the stream catch floating debris (leaves and sticks) in the stream and can cause obstructions in the stream which the stream temporarily overtops the banks.

Pond at Town Hall:

Description of work:

Currently there is a 15” HDPE pipe which is the only outlet from a pond/wetland system which is known as Town Hall pond.   The proposed retrofit at this location involves adding a perforated HDPE riser to the end of the existing outlet pipe to allow for a temporary increase in ponding and thus increased residence time for the runoff directed to the pond from the recently constructed East Hampton Town Hall as well as high density residential housing.   The temporary increased residence time will allow for more fine sediments in the runoff to settle out within the pond/wetland system.   Additionally, the temporary increased residence time will allow nutrients in the runoff to be taken up by aquatic vegetation within the pond/wetland system.

Paul and Sandy’s Too:

Description of work:

Paul and Sandy’s nursery currently has an excavated pond which is used for irrigation water for the nursery.  Structural drainage systems within the site convey runoff to the pond.   Because of the depth of the structural drainage where it enters the pond, there are no options to improve the pollutant removal within the pond without compromising the capacity of the pond for irrigation.

Discharges from the pond are via a wide, shallow spillway located at grade at the northwest corner of the pond.   This discharge joins flow from a discharge from the CT DOT drainage system on Route 66.   All the flows go through a wooded wetland area prior to passing through a culvert under Old Marlborough Road and then into an open ditch on private property which then enters the lake.

Please keep in mind these dates are just estimates and things can and most likely will change as we continue along. If you have any questions please feel free to reach out to me.