National Program for Inspection of Non-Federal Dams. Chaffin Pond Dam (MA 00621), Merrimack River Basin, Holden, Massachusetts. Phase I Inspection Report.
CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV
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Chaffin Pond Dam is actually a section of roadway embankment approximately 135 ft. long, 11 ft. high and with a minimum width of 100 ft. Three submerged culvert outlets pass through the dam between upstream and downstream headwalls, allowing the water level to be the same on both sides of the dam. The control entrance to the assumed 30-in. diameter outlet on the left side has slots for stoplogs however, none are in place. The control for a 4-ft. box culvert in the center is an open wood gate. The third outlet culvert is also gated but apparently blocked. Water from Chaffin Pond flows to outlet works at a second pond downstream from the dam where water is drawn for hydraulic research purposes. The dam is in poor condition, based on a visual examination of the structure. The headwalls have experienced major structural failures and the potential for a collapse of the upstream headwall with possible obstruction of flow to the outlet does exist. Hydraulic analyses indicate that the test flood would surcharge the pond by 680 acre-ft. and raise the pond level to about 4.2 ft. below the top of the dam. Therefore, no overtopping would be expected.
- Hydrology, Limnology and Potamology
- Civil Engineering