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w r Recommended Management Actions Short-term/on - ime There are a series of actions which should be taken immediately as a means to refine future activities. These are generally, one-time actions and include: 1. Clean out the spillway. As mentioned above, the spillway now contains sand, gravel, rocks, and pieces of asphalt. These prevent the boards from being easily and effectively manipulated--either for water control or fish passage--and also prevent the efficient passage of water if necessary. The spillway should be cleared of these obstacles to ensure proper operation. This effort should also include clearing of the portion of the pond between and leading into the jetties as necessary to make possible a smooth flow through the spillway, even with all boards removed. Sand may be moving along the pond edge and around the ends of the jetties because the "pockets" at the base of the jetties are too full to capture it. This should be reviewed and, if necessary, the "pockets" should also be cleared out. If these "pocket" areas are maintained adequately in the future, material may not accumulate in the spillway itself. 2. Take accurate dimensions of spillway and prepare an as-built plan. Because the base of the spillway is currently covered with rocks, sand, and gravel, it is impossible to be sure of its elevation, construction, and design. Consequently, the calculations in the preceding discussion were based on best available information. Once the spillway has been cleaned and more accurate measurements taken, if the measurements vary from what were used above, the calculations should be refined. Preparation and maintenance of an as- built plan may help to avoid a similar situation from occurring in the future. 3. Establish clear responsibility for maintaining the spillway. There are two aspects to this task: 1) operation of the boards to provide for fish passage and pond level control, and 2) maintaining the structure itself in an operable fashion, including as-needed cleaning of materials which may get into the spillway. At present the Herring Warden (and the state Division of Marine Fisheries) manage item 1. There seems to be no clear responsibility for item 2. 4. Calibrate flow rate versus the height of water flowing over the boards as a means of utilizing the latter as a simple measure of outflow rate. Relate this to the flow rates over the fish ladder in the millpond adjacent to Route 130. Once the spillway is clear and operating efficiently, perform a series of tests to verify that the head (height of water flowing over the boards) can indeed be Horsley & Witten, Inc. Mashpee-Wakeby Pond Management Plan Page 28