Melville Ponds Restoration Survey July 19, 2007 At their Wednesday, June 13, 2007 meeting, the Melville Ponds Committee decided by consensus to pursue the possibility of restoring (Repair the dams and dredge sediment from the ponds) the seven intermediate ponds to their earlier functional state. Mike Kenyon of USDA was invited to view the ponds and offer advice and assistance in obtaining grants for this purpose. It is considered a large project that may require being done in stages over several years and several grants. At the July 11 meeting, Pat Higgins was appointed to lead this effort and on July 19, he, Chairman Ed Rizy and Thurston Gray visited the ponds to determine which pond(s) should be restored first. Criteria considered were 1) Ease of access by the equipment, 2) Visibility of progress and the final result, 3) Ease of disposal of the dredging spoils, and 4) Relative amount of effort required for each pond. It was generally agreed that Pond 5 best met these criteria, with Pond 7 to be included if possible within the size constraints of the first phase and then Pond 8. History It is said that the Navy dammed the stream to build the series of ponds for the purpose of creating silt traps to protect Melville Lower Pond from becoming filled with silt. The Lower pond was used as a fire fighting reservoir for the coaling station, later the Navy Fuel Depot. The ponds were cleaned on a periodic basis until the property was turned over to the Town of Portsmouth in the early 1970s. Evidence of the dredging can be found in mounds nearby. Since that time, nature has had its way. The dams have detioriated, the ponds have filled with silt, trees have fallen and the area has become overgrown with vegitation, some within the ponds. Pond by Pond results The second pond is, by far, the largest of the intermediate ponds. It is highly visible, believed to be shallow and badly in need of dredging. The surface is covered from shore to shore with duckweed and other aquatic vegitation, believed to be nourished by nutrients being released from the bottom sediments. It is believed to be the home of snapping turtles, reported to have bass and a family of ducks live there. Although we did not inspect the dam, it is believed to be in relatively good condition as it controls the water to a relatively constant level. In spite of all of this, the second pond was not given serious consideration for phase 1 restoration because its sheer size would make equipment accessability difficult in some areas and the volume of spoils would likely have have to be disposed off-site. Pond 3 was not visited due to it's inaccessability and alledged location in a wet area. Likewise we did not get to see Pond 4. However, we did get close enough to hear it's waterfall. It was the loudest of any of the waterfalls and for this reason we believe the pond to be full (of water) and the dam to be intact. The pond is located under a power transmission line and screened from our view by a patch of cattails. Our position was at the dead end of a well traveled extension of the (now discontinued) Green Trail. Pond 5 is accessable through the campground and for this reason, work should probably be performed off-season. The dam is relatively intact with only a short section of its upper edge chipped off. This dam, along with most of the others can best be described as a stone wall that has been filled, capped and encapsulated with cement. It seems that standard practice in building dams of this sort is to incorporate a drain in the lower central portion to allow the water to pass while the dam is being built and the cement is curing. And subsequently to plug it or gate it and allow the pond to fill. The drain was made by using a short piece of 15" more or less diameter galvanized corrigated steel culvert. At some point in time, this drain must have failed, as it has been repaired by casting a large block of cement with a slot for a plank or metal gate on the upstream side of the dam. No plank or gate was found and no water in the pond, save a small central stream. The cement block has pulled away from the face of the dam a little and will need to be resealed. The sediment is well exposed and there is room to deposit it nearby as has been done in the past. Visibility is good for those camping in the vicinity and could be achieved easily for hikers by resurecting the Green Trail. If things took a turn in that direction, Pond 5 would be the most likely candidate for a do-it-yourself project. Pond 6 is also accessable through the campground, but with a little more difficulty than pond 5. The drain, if there is one, is still sealed and the water level is nearly at the top of the dam. Likewise, the sediment level is near the top of the dam, but still underwater. Due to it's continually available moisture content, there is quite a bit of vegitation growing out of the dam itself. Due to the perceived sediment depth, there is probably more to be removed, but still space nearby to deposit it. Likewise, the dam will need more work. Pond 6 is visible from certain other tent sites and from the Green Trail. Pond 7, with a little work, is accessable on the east from Bayview Terrace and on the west via a road from the campground. The drain is passing water, but for some reason, the water and the silt in the pond are at a higher level than the drain. This pond, to me, appears to be larger than Ponds 5, 6 and 8 and probably 3 and 4. The dam needs more work that Dam 5 but is in a better condition than Dam 6. Again, there is room nearby to deposit the spoils. It is visible from Bayview Terrace but would be even better from a resurrected Green Trail. Ed and I later visited Pond 8. It needs to be cleaned out, but the dam is in good shape, needing only preventative maintenance. Equipment access could be achieved via Mott Farm Road, the west branch of the Yellow Trail, which was formerly a road and then up a slight incline which is also part of the Yellow Trail. Once again, there is space nearby in which to deposit the spoils. This pond already has as much visibility to hikers and Lower Pond fishermen as the Lower Pond itself. Most ponds have bushes and trees growing in the sediments at the edge of the pond. In addition, trees, reaching for sunlight have grown out over the ponds and, in some cases, have fallen in. These need to be removed. But, in addition to this, there are very few mature trees that would need to be removed to permit equipment access.

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