The dam facility consists of a 325 foot long masonry spillway and a 335 foot long earthen embankment which span the Farmington River and are referred to as the main dam. The top of the earthen embankment is approximately 32 feet above the downstream riverbed. There are two other dams adjacent and perpendicular to the downstream face of the main dam. The 100 foot long forebay dam impounds the forebay, the body of water downstream of the left end of the dam which is utilized for industrial purposes by the adjacent factory. The wing dam, a 200 foot long abutment consisting of a 160 foot long spillway and a 40 foot long abutment located at the right end of the main dam, was originally intended to route flow to an adjacent powerhouse, which is no longer operational. Outflow from the project is over the three dam spillways and through eight sluice gates on the main dam, one mid-level and three low level sluices, as well as the closed intakes to the powerhouse, on the wing dam, and from a 42 inch square sluice and a 60 inch diameter pipe on the forebay dam. Based upon the visual inspection at the site, past performance of the dam, and existing data, this dam is judged to be in good condition. No evidence of instability was observed in the main dam or the two appurtenant dams. Based upon two existing flood plain reports and our computations, the spillway capacity is 55,000 cfs, which is equivalent to approximately 66% of the routed test flood outflow.

This facility is a 400 foot long concrete gravity dam across the Farmington River consisting of a 40 foot long right abutment housing three low level sluicee gates, a 300 foot long spillway, and a 60 foot long left abutment with a brick gatehouse housing six intermediate level sluice gates. The hydraulic height of the dam is approximately 33 feet. The six sluices in the left abutment discharge to a 640 foot long canal feeding a powerhouse at the end of the canal, which is not presently in use. The canal was excavated in the left riverbank and is lined with a concrete wall on the right side and a masonry wall on the left side. Based upon the visual inspection at the site, existing data, and past performance, the dam is judged to be in fair condition. No evidence of immediate structural instability of the dam or its appurtenances was observed, however, there is spalling of concrete on the abutments, canal walls, powerhouse bulkhead, and most probably on the crest and downstream face of the spillway and there is a seep at the juncture of the right abutment of the dam with the adjacent bedrock riverbank. The spillway capacity to the top of the dam is 33,000 cfs, which is equivalent to approximately 40% of the routed test flood outflow.

Upper Mill Pond Dam is a stone masonry dam approximately 100 feet long and 15 feet high. The spillway is 92 feet long, 9 feet wide and consists of a masonry broad crested weir. The water level is at the spillway crest and can be lowered by opening the low-level discharge gate which was recently made operable by the Middletown Water Department. In general, the overall condition of the dam is FAIR. The structural stability of the dam is good as evidenced by its vertical, horizontal and lateral alignment. The stone masonry is in good condition although moss and weeds are growing from the joints. The spillway weir and east abutment are in good condition. The west abutment is badly spalled at its base. The discharge gate inlet structure is badly spalled and the bar rack is cluttered with debris. There is some seepage at the east end of the dam where the stone masonry meets the abutment/ledge interface. Vegetation is growing around this area as well. The ledge continues along the downstream channel bank and there is minor seepage. A drainage pipe outlets above the west abutment. There is presently a scour hole at this location. This scour hole has caused the last section of the drainage pipe to collapse into the hole and is undermining the west spillway abutment. At the spillway elevation, the water surface area and storage capacity is 5 acres and 31 acre-feet respectively. The spillway capacity when the water level in the pond is at the top of the dam is 250 cfs. The test flood will overtop the dam by 1.8 feet.

Upper Pond Dam is an earth embankment dam with a maximum height of 17 feet and a length of 390 feet. The dam embankment left of the spillway is approximately 10 feet in width, with 2 horizontal to 1 vertical upstream and downstream embankment slopes. The centrally located spillway is 72 feet in length and is a stone masonry structure. Stone masonry training walls approximately 5 feet in height are located at each side of the spillway. The outlet works consist of a concrete gate structure and an outlet channel. Based on the visual inspection, the Upper Pond Dam appears to be in poor condition. There was no movement or settlement of the crest observed. The horizontal alignment is good. The top of the outlet gate structure, however, is lower than the embankment crest. Some erosion was noted at the abutments, adjacent to the spillway section and adjacent to the outlet works. Trespassing on the slopes was not significant. Erosion scarps on the upstream slope extending 1-2 feet above waterline were noted. Several areas of broad shallow erosion on the upstream slope and upstream side of abutments were observed. Brush and many large trees (up to 2.5-ft.-dia.) with extensive root systems were noted on the slopes and crest of the dam. Standing water was observed in an area 35 feet downstream of the toe on the right side of the dam. The capacity of the spillway is inadequate to pass the 1/2 PMF test flood outflow of 5,195 CFS and would overtop the dam by about 0.9 feet. The spillway can pass about 33 percent of the test flood.

The dam is constructed of reinforced concrete and earth fill. It is about 225 ft. long and 16.6 ft. high. The dam is small in size with a high hazard potential. The dam is in poor condition at the present time. The spillway is capable of passing 5% of the Test Flood routed peak outflow. (Author).