GROTON–Following is the prepared text of remarks by Edward G. Martin, chair of the Groton Shellfish Commission, at the first session, held Dec. 1, 2010, of the Zoning Commission hearing on proposed changes in regulations on stormwater management and erosion and sediment control:

The Groton Shellfish Commission (GSC) at the Oct. 14th regular meeting has reviewed the proposed amendments to the current Erosion and Sediment Control plan and stormwater management plan.

The proposed changes requested represent an improvement, particularly the requirement that the plan would follow the “Connecticut Guidelines for Soil Erosion and Sediment Control (2008).”  For stormwater control the plan would adhere to Best Management Practices (BMPs) consistent with the Connecticut Stormwater Quality Manual of 2004.

However, the Groton Shellfish Commission is particularly concerned that in the regulations there are no standards proposed to measure the purity of stormwater runoff as it discharges into the various salt water estuaries of Groton. A healthy productive bed (clams, oysters, scallops etc.) requires a plentiful supply of clean water. The Connecticut Department of Agriculture, Bureau of Aquaculture (CT DA/BA) requires that to be classified as an open shellfish bed the water must average less than 14 fecal coliform per 100 ml. To put that requirement in perspective, one human [fecal] waste would have to be diluted with 8 million gallons of water to pass.

Recent history has seen a gradual closing of shellfish beds in CT, mainly due to poor water quality resulting from contaminated stormwater discharge. Salt water estuaries west of the CT River are now closed to recreational shell fishing. Many are also closed to swimming (to be classified acceptable for swimming, a coliform level must be 100 coliform per 100 ml or less.)

An analysis of water quality in Groton salt water estuaries has shown a gradual decrease in quality. Some of its estuaries (Pine Island, Baker Cove, West Cove) are closed to recreational shell fishing. The open areas (Poquonnock River, Mumford Cove, Palmer Cove, parts of the Mystic River) are often closed during periods of heavy rainfall. To understand the dynamics of what happens in a particular salt water estuary, the model show below is proposed. (Attachment 1) [The attachment is omitted from this text. It illustrates how the level of coliform bacteria count in an estuary is a balance struck between pollution flowing from upstream and the purging effect of clean water coming from tides of the Long Island Sound.]

Using GIS technology and with the help of Andrew Bowne [town GIS staff], a map of Groton’s main salt water estuaries was prepared showing the upstream drainage area (watershed) and the percentage of impervious surface. The table below illustrates the key factors. The map is available in the shellfish office at the Noank Hatchery.

Table 1

Salt Water Estuary……….Shell fishing Status………Imperv. Surface in W’shed

 Pine Island………………….Closed………………………….24%

Baker Cove…………………..Closed………………………….33%

Poquonnock River………..Open……………………………..9.5%

Mumford Cove……………..Open……………………………..9.0%

West Cove……………………Closed………………………….30%

Beebe Cove………………….Area utilized for leasing…..10.9%  [Commercial use]

Mystic River………………..Open……………………………..9.1%

Palmer Cove………………..Open…………………………….10.5%

 As shown in the table above, there is a direct correlation between the amount of impervious surface in the watershed area draining into the estuary and the shell fishing status of the estuary. When the impervious area is less than about 10%, the estuary in question is almost always open to recreational shell fishing. If the watershed impervious area exceeds 25%, the estuaries are closed to shell fishing.

 It is the opinion of the GSC that the table above best describes where we are now. What is needed is some appropriate analytical test that can be routinely applied that will be predictive of future downgrading of the estuary that will require closing of the shellfish beds.

 The GSC has identified key streams leading into each estuary in Table 1. We plan to periodically monitor the purity of the sample site using a battery of tests (i.e. dissolved oxygen, pH, fecal coliform level, chemical oxygen demand, dissolved solids, etc). With help from Pfizer, we are presently setting up a laboratory at the Noank Hatchery to facilitate the program.

 Our objective is to develop a test (s) that best predicts an impurity level that will eventually close the estuary to recreational shell fishing. In this way, we can inform Town Planners that corrective action will soon be needed (limits of non-porous areas, special treatment of stormwater discharge, limits of building area, etc).

 Any comments/suggestions are welcomed.

       /s/ E.G. Martin

           Chair,  Groton Shellfish Commission