National Program For Inspection Of Non Federal Dams Noone Mills Dam Nh 00427 Nhwrb Number 19102 Merrimack River Basin Peterborough New Hampshire Phase I Inspection Report

The dam is a stone-filled, concrete capped gravity overflow structure about 20 ft. high and 267 ft. long. The dam is considered to be in poor condition. It is small in size with a high hazard classification. There are a few major concerns which must be attended to. The potential for the loss of more than a few lives and extensive economic loss would exist. (Author).

The Souhegan River Watershed Dam No. 26 is located on Blood Brook, a tributary of the Souhegan River, approximately 2 miles upstream of West Wilton, New Hampshire. The dam is an earth embankment 692 feet long and 79 feet high with a drop inlet service spillway structure and a 30 inch outlet conduit. An emergency spillway 320 feet wide is cut into the left abutment.

The dam is intermediate in size with a low hazard potential. The hydraulic analyses indicated that the spillway test flood in Highland Lake is 11800 cfs, of which the North Outlet would experience 3950 cfs. It is recommended that the refined hydrological analyses elsewhere recommended for Highland Lake's South Outlet be undertaken. (Author).

The dam is about 720 ft. long and 35.5 ft. high. It is intermediate in size with a high hazard potential. In the event of failure of the dam, there is the potential of significant property damage and loss of life could result. The dam is in good condition at the present time. No conditions were observed which require additional investigation. There are a few remedial measures which should be implemented by the owner.

The Souhegan River Watershed Dam No. 10A is located on Mill Brook approximately one mile upstream of Davisville, N.H. The dam is an earth embankment 951 feet long and 59 feet high with a drop inlet service spillway structure and a 30 inch outlet conduit. An earth emergency spillway 220 feet wide is cut into the left abutment. An earth emergency spillway 110 feet wide is cut into the right abutment. The dam is intermediate in size with a high hazard potential. The dam is in good condition at the present time. It is recommended that the owner retain the services of a registered professional engineer to investigate the cracking and erosion of the outlet conduit. Keywords include: Visual inspection, Dam safety, Merrimack River Basin, Wilton, New Hampshire, and Mill Brook, a Tributary of the Souhegan River.

The dam is an earthen embankment about 420 ft. long with a maximum height of about 25 ft. The dam impounds water from the Brook and the spillway discharges to Harris Pond immediately below the dam. The dam is considered to be in fair condition. It is intermediate in size with a significant hazard potential. (Author).

The dam is a 188 ft. long, 16 ft. high earth embankment dam. The condition is fair. The visual inspection did not disclose any immediate safety problems. The dam's spillway will not pass the test flood, therefore it is recommended that the owner engage a qualified engineer to evaluate further the potential for overtopping the inadequacy of the spillway. (Author).

The dam is an earth embankment dam 695 ft. long and 69 ft. high. It is intermediate in size with a high hazard potential. The test flood for the dam is the PMF. The dam is in good condition at the present time. There are various remedial measures which should be implemented by the owner. The program of annual technical inspections should be continued. No conditions were observed which require further investigations.

Mountain Pond Dam is located on the north end of Mountain Pond in Sanbornton, N.H., in mountainous terrain two miles south of the village of New Hampton. The dam is an earth embankment, 97 feet long and 14 feet high with a gated 8-inch outlet. The impoundment stores the water supply for the Town of New Hampton and is also the fire protection reserve. It is small in size with a low hazard potential. The test flood is in the range of a 50 to 100 year frequency. The condition of the dam is considered to be fair, requiring that modifications be made by the owner within 1-2 years after receipt of this inspection report. Keywords include: Inspection, Dam safety, Merrimack River Basin, Sanbornton, New Hampshire, and Tributary of Pemigewasset River.

St. Pauls School Dam is a concrete overflow section approximately 15 ft. high from the bottom of the upstream channel to the top of the training walls and approximately 100 ft. long between the training walls. The upstream face of the concrete section is vertical and measures approximately 9 ft. from its crest to a concrete apron on the channel bottom. The dam is in fair condition at the present ime, with a few major concerns which must be corrected. The size is intermediate with a significant hazard potential. The dam could be damaged by the discharge over the abutments. It is not anticipated that lives would be lost. Keywords include: Visual inspection, Dam safety, Merrimack River Basin, Concord New Hampshire, and Turkey River.