National Program For Inspection Of Non Federal Dams Lochmere Dam Nh 00015 Nhwrb 2107 Merrimack River Basin Belmont New Hampshire Phase I Inspection Report

The dam is 223 ft. long and about 14 ft. high. The dam is intermediate in size with a hazard potential of significant. The dam is in good condition at the present time. Only a few relatively minor operating and maintenance improvements are necessary. The owner should implement a formal, written flood and emergency warning system. (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 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).

Kelleys Falls Dam is a run of the river type dam, with an overall length of 503 feet. Visual inspection of the dam indicated that the dam is in poor condition. The inspection revealed a number of leaks through the mass concrete spillway section, considerable loss of concrete from the spillway section, seepage around the concrete wall on the right side of the dam, and general deterioration of concrete on the abutments and hydro-building. Based on the intermediate size of the dam and the significant hazard classification and in accordance with Corps of Engineers guidelines, the test flood is one half the Probable Maximum Flood (PMF) or 55,900 cfs. The one half PMF outflow overtops the dam by 6.8 feet. With the water level at the top of the dam, the spillway will pass 38 percent of the test flood outflow. It is recommended that the owner engage a qualified engineer to make thorough investigation of the condition of the foundation of the spillway section of the dam, investigate the structural stability of the spillway section and ways to increase the spillway capacity. Also, the owner should remove the flashboards on the dam immediately. Additional keywords: Merrimack River Basin, Manchester, and New Hampshire.

The Souhegan River Watershed Dam No. 14 is located on Furnace Brook approximately 1/2 mile upstream of New Ipswich Center, NH. The dam is an earth embankment 1,500 feet long and 35 feet high with a drop inlet service spillway structure and a 30 inch outlet conduit. An earth emergency spillway 120 feet wide is cut into the left abutment. It is small in size with a high hazard potential. The test flood is the PMF. The dam is in good condition at the present time although there were some remedial measure which must be undertaken by the owner. No conditions were observed which require additional investigation. Keywords include: Visual inspection, Dam safety, Merrimack River Basin, New Ipswich, New Hampshire, and Furnace Brook tributary of Souhegan River.

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.

The dam is an earthen embankment structure with a central concrete core wall about 147 ft. in overall length and 9 ft. high from the crest of the dam to downstream toe. The dam is considered to be in fair condition. It is classified as small in size and significant in its hazard classification. (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.

The dam is a stone masonry gravity dam with a total length of about 325 ft. It is small in size with a low hazard potential. The dam is in fair condition at the present time. In light of the dam's fair condition, technical inspections should be made every year. (Author).

The dam is a 33 ft. high gravity concrete and gravity stone masonry dam capped with concrete. It is about 400 ft. long. It is small in size with a significant hazard potential. The dam is in fair condition at the present time. There are various remedial measures that the owner should implement.