Download or read book National Program for Inspection of Non Federal Dams Moodus Reservoir Dam CT 00350 Connecticut River Basin East Haddam Connecticut Phase I Inspection Report written by CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV. and published by . This book was released on 1978 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt: Moodus Reservoir is a homogeneous earth embankment dam constructed around 1824. The dam has a maximum height of 17.5 feet and is approximately 275 feet long. The dam consists of a mortared stone spillway 140 feet long by 15 feet in height. An earth embankment with a total length of 135 feet is located to the left of the spillway. The overflow spillway discharges into a stone and concrete lined channel leading to an 18 foot by 8 foot bridge opening beneath Falls bashan Road, which is immediately downstream. this bridge has a wooden deck and a load capacity limited to 5 tons per axle. The earth embankments are approximately 2.5H:1.0V and are grassed on the crest and both slopes. There is also an outlet structure with a discharge opening measuring 7 feet by 3 feet at the left spillway abutment of the dam which discharges through a separate stone masonry channel beneath Falls Bashan Road. Due to its age, Moodus Reservoir Dam was neither designed nor constructed by present State-of-the-art methods. Based upon the visual inspection at the site, the lack of engineering data available, and very limited operational or maintenance evidence, the dam is judged to be in good condition. However, there are areas of concern which must be corrected to assure the safety and long-term performance of this dam. It is estimated that a test flood outflow of 6898 cfs (657 csm) will overtop the dam by about 3.7 feet; therefore, the spillway is considered inadequate. With the pool level at the top of the dam, the spillway can discharge 2182 cfs, or 32 percent of the test flood outflow.

Download or read book National Program for Inspection of Non Federal Dams Higganum Reservoir Dam CT 00430 Connecticut River Basin Haddam Connecticut Phase I Inspection Report written by CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV. and published by . This book was released on 1978 with total page 127 pages. Available in PDF, EPUB and Kindle. Book excerpt: The crest is generally grassy and the downstream slope is heavily overgrown with trees and shrubs. The upstream face is riprapped above water level and to a depth of about 3.0 feet below the normal water surface. The spillway is located in the center of the embankment and is roughly semicircular and contained between vertical masonry walls. The spillway is constructed of cut stone masonry and flows discharge onto a slab paved with stone blocks leading to a natural stream bed. This dam is considered to be in POOR condition. The visible signs of distress which indicate a potential hazard at this site are: large, wet, spongy areas generally along the entire right toe and lower slope of the dam embankment indicative of seepage; an extremely steep downstream slope; a dense large growth of trees and shrubs on the downstream slope; the small storage capacity of the reservoir relative to its drainage area; the close proximity of the populated area immediately downstream; seepage through the spillway masonry joints and a general lack of proper, regular maintenance. The maximum spillway discharge of 5710 cfs represents 48.5 percent of the test flood outflow.

Download or read book National Program for Inspection of Non Federal Dams Risley Reservoir Dam CT 00211 Connecticut River Basin Vernon Bolton Connecticut Phase I Inspection Report written by CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV. and published by . This book was released on 1978 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: The dam is located on a tributary of the Connecticut River on the town line of Bolton and Vernon, Tolland County, Connecticut. It is an earthfill structure approximately 625 ft. long with a maximum depth at its center of 26 ft. The crest width varies from 12 to 15 feet. A vertical granite masonry wall extends from the downstream side of the crest to the bed of Lydall Brook below. The visable part of the upstream embankment has a 1 on 2 to 1 on 3 slope with a riprap face. The downstream embankment consists of cobbles and boulders piled against the face of the masonry wall on an approximate 1 on 1.5 slope. The dam is in generally good condition. It appears to be structurally stable at the present time under normal conditions. Based on its small size and high hazard classification in accordance with the Corps' guidelines, the test flood is 1/2 the PMF. The spillway will pass only about 44 percent of the test flood and is considered inadequate. Recommendations to improve dam safety are: (1) Increase spillway capacity; (2) Replace 6-in. discharge pipe and relocate valve; (3) Add riprap near the center on the downstream side; (4) Divert spillway discharge away from the toe of the dam.

Download or read book National Program for Inspection of Non Federal Dams South Reservoir Dam CT 00487 Dike CT 01709 Connecticut River Basin Farmington West Hartford Connecticut Phase I Inspection Report written by CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV. and published by . This book was released on 1981 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: This flood control project consists of a dam and dike which are earth embankments at 3H:1V with good grass cover and a top width of 12 feet. The dam is approximately 3060 feet long and 31 feet high. The dike is approximately 475 feet long and 28 feet high. The principal spillway consists of a reinforced concrete riser, a 30 inch RCP through the dam and a reinforces concrete impact basin. The emergency spillway is a 130 foot wide grassed earth channel at the eastern end of the dam. The reservoir is normally empty except for a small sediment pool. Based on the visual inspection, review of design information, and past operational performance, the dam and dike are judged to be in GOOD condition. There is some erosion due to vehicle trespass and animal burrows were noted in the embankments. The maximum outflow capacity of the spillways with the water level at the top of the dam is 3580 cfs, which is 185 percent of the test flood outflow.

Download or read book National Program for Inspection of Non Federal Dams Bashan Lake Dam CT 00354 Lower Connecticut River Basin East Haddam Connecticut Phase I Inspection Report written by CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV. and published by . This book was released on 1979 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt: The dam is a gravity stone wall-earth fill structure founded on rock with a near vertical partially arched granite block retaining wall on the downstream face, and a concrete retaining wall on the upstream face. The dam rises approximately 23 feet above the bed of the Moodus River and has a maximum top width of 35 feet and a length of 169 feet. The spillway is a 29 foot long, broad crested weir of trapezoidal cross-section with an inclined sand and gravel upstream approach and a natural rock exposure as a downstream discharge channel. The low level outlet, a stone culvert approximately 2.1 by 2.5 feet in size discharges at approximate elevation 364.7 to a naturally eroded rock channel. The size, type and invert elevation of the upstream inlet was not ascertained. The gate is operable, but not only with difficulty. Based upon the visual inspections at the site, the dam appears to be in fair condition. No instability of the dam was observed, however conditions were identified which could have a direct bearing on the future stability of the dam. One such condition was in the area of the spillway where significant flow was coming from between and below the granite blocks directly under the spillway crest. The other major concern is the insufficient capacity of the spillway itself. There are other areas requiring monitoring and minor maintenance, as well. The Test Flood will be equivalent to one-half the Probable Maximum Flood (PMF). Peak inflow to the lake is 2200 cfs; peak outflow (Test Flood) is 700 cfs with the dam overtopped 1.0 feet. Based upon our hydraulics computations, the spillway capacity is 165 cubic feet per second (cfs), which is equivalent to 24% of the Test Flood.

Download or read book National Program for Inspection of Non Federal Dams Scovill Reservoir Dam CT 00431 Lower Connecticut River Basin Haddam Connecticut Phase I Inspection Report written by CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV. and published by . This book was released on 1980 with total page 89 pages. Available in PDF, EPUB and Kindle. Book excerpt: Scovill Reservoir Dam is an earth embankment dam with stone masonry walls on the upstream and downstream faces. The dam is about 245 feet long, with a maximum height of 21 feet. A spillway section about 25 feet wide and 1 foot deep is located in the central portion of the dam. An abandoned gate structure is located near the spillway section. The dam is judged to be in poor condition. The upstream face of the dam has been overtopped and extensive erosion of the crest is unchecked. Brush is growing on the upstream slope and crest. The downstream area, just below the dam, is wet and spongy, with some seepage observed. Trees are growing at the base of the downstream stone masonry face. The spillway, which consists of an unlined section at the crest where the downstream masonry wall is stepped-down, has eroded significantly and water flowing over the crest continues to cause erosion. The capacity of the spillway is inadequate to pass the 0.75 PMF spillway test flood outflow without overtopping the dam. The test flood would overtop the dam by about 0.7 feet. The spillway would pass only about 14 percent of the test flood outflow without overtopping the dam.

Download or read book National Program for Inspection of Non Federal Dams Hallmere Reservoir Dam CT 00249 Connecticut River Basin Berlin Connecticut Phase I Inspection Report written by CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV. and published by . This book was released on 1979 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hallmere Reservoir Dam is an earthfill embankment about 570 ft. long and 45 ft. high. It has a concrete core and a riprap covered upstream face. It was constructed in 1896-97 for purposes of water supply. A 30 ft. wide masonry waste-way with s ill and flashboards serves as the spillway. The only regulated outlet is a 20 in. dia. concrete pipe. The maximum storage capacity of the reservoir to top of dam is about 585 acre ft. and the drainage area is about 1 sq. mi. The dam appears to be in fair condition. Brush and tree growth has begun to intrude on the slopes and crest of the embankment. Seepage was noted at the downstream toe of the dam. Animal burrows and missing riprap was apparent on the upstream slope of the embankment. The test flood inflow is 3200 cfs. The routed test flood outflow (2,900 cfs) overtops the dam by 0.7 ft. The spillway is adequate to pass an outflow corresponding to about 51 percent of the routed test flood outflow but the spillway and discharge channel walls would be overtopped by about 5 ft.

Download or read book National Program for Inspection of Non Federal Dams Upper Pond Dam CT 00433 Lower Connecticut River Basin Haddam Connecticut Phase I Inspection Report written by CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV. and published by . This book was released on 1980 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book National Program for Inspection of Non Federal Dams Buckingham Reservoir Dam CT 00244 Connecticut River Basin Glastonbury Connecticut Phase I Inspection Report written by CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV. and published by . This book was released on 1980 with total page 117 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Buckingham Reservoir Dam is an earth embankment 400 feet in length and 30 feet in maximum height. The spillway is 50 feet long, constructed of concrete. As a result of the visual inspection and the review of limited available data regarding this project, the dam, spillway and dike appear to be in poor condition. The vertical and horizontal alignment of the dam is good. The downstream slope has several trees and high brush, especially at the abutments. Erosion gullies up to 8 inches deep on the downstream slope, due to vehicular traffic, were noted. The riprap on the upstream slope is in good condition with a few unprotected areas. Considerable seepage as evidenced by wet area downstream from the toe of dam and at the toe of the natural slope at the left abutment was noted. Several springs were observed, although these springs did not appear to carry fine material. The concrete spillway and dike are in fair condition. The concrete spillway had areas of erosion, spalling and deterioration. Seepage was noted at the base of the left training wall. The dike was overgrown with brush; however, no seepage was observed. Apparent settlement or slumping was observed at upstream edge of dike's crest immediately to the right of the spillway. Apparent movement has occurred at the downstream toe adjacent to the left spillway training wall. The vertical and horizontal alignment was good. A few minor erosion gullies were noted on the downstream slope. The capacity of the spillway is adequate to pass the 100-year test flood outflow of 1,260 CFS without overtopping the dam and dike.

Download or read book National Program for Inspection of Non Federal Dams Norwich Reservoir Dam VT 00157 VTDWR 146 1 Connecticut River Basin Norwich Connecticut Phase I Inspection Report written by CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV. and published by . This book was released on 1981 with total page 95 pages. Available in PDF, EPUB and Kindle. Book excerpt: The dam is a concrete arch with thrust walls and a concrete crib with earth backfill. The dam is about 200 ft. long with a maximum height of 28 ft. The dam is small in size with a high hazard potential. The dam is in poor condition at the present time. There are various remedial measure and recommendations which must be undertaken by the owner.

Download or read book National Program for Inspection of Non Federal Dams Lower Hart Pond Dam CT 00247 Connecticut River Basin Berlin Connecticut Phase I Inspection Report written by CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV. and published by . This book was released on 1981 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt: The drainage area is 2.0 square miles and the reservoir has 825 acre-feet of storage capacity. The assessment of the dam is based on a visual inspection, past operational performance and hydraulic/hydrologic computations. The dam is judged to be in FAIR condition with several areas that require attention. These areas include seepage through the dam in the vicinity of the low-level discharge pipes and wet spots along the toe of the dam, vegetation on the embankments as well as along the toe of the dam and the inoperable status of the low-level discharge pipe. The test flood outflow will not overtop the dam and will leave 0.4 feet of freeboard.

Download or read book National Program for Inspection of Non Federal Dams Middle Reservoir Dam CT 00590 Housatonic River Basin Seymour Connecticut Phase I Inspection Report written by CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV. and published by . This book was released on 1980 with total page 83 pages. Available in PDF, EPUB and Kindle. Book excerpt: The dam of the Middle Reservoir is a concrete and masonry structure. It is approximately 300 feet long, 27 feet high and has an average top width of 8 feet. Based on visual inspection and past operational performance, the dam is judged to be in FAIR condition. Seepage and vegetation was noted on the downstream face and the crest is chipped and spalled due to an unfinished rehabilitation project. The test flood for this dam is 1/2 the Probable Maximum Flood (PMF). The test flood has an inflow equal to 770 cfs and an outflow discharge equal to 765 cfs with a stillwater elevation of 269.4 which will overtop the dam by 1.0 feet. These values represent no flood storage in the upstream Beaver Lake. If use is made of the storage capacity of Beaver Lake, the flood inflow to the Middle Reservoir can be greatly reduced. The dam was not overtopped in the 1955 flood because Beaver Lake was low. The maximum outflow capacity of the spillways under a stillwater condition is 132 cfs, which is 17 percent of the test flood.

Download or read book National Program for Inspection of Non Federal Dams Bloomfield Dam CT 00492 Connecticut River Basin Bloomfield Connecticut Phase I Inspection Report written by CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV. and published by . This book was released on 1981 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bloomfield Dam consists of an earth embankment approximately 4,550 ft. long, with a top width of 12 ft. and a maximum height of 29 ft. In addition, there is a 750 ft. long dike 10 ft. high with a 10 ft. top width. The two outlets for the dam are the unregulated principal spillway and emergency spillway. The principal is a drop inlet structure consisting of a two stage reinforced concrete intake riser discharging through a 36 diameter, 177 ft. long reinforced concrete pipe under the dam embankment. The emergency spillway is a trapezoidal grassed channel, 175 ft. wide at the control section with its crest 5.0 ft. below the top of the dam. Based on visual inspection and review of available plans and reports, the Bloomfield Dam is judged to be in good condition. Some features found existing that could affect the stability of the dam are, wheel ruts and erosion gullies along the crest and slopes and damage by burrowing animals. The dam is a flood control project and, therefore, the reservoir is dry except during periods of heavy rainfall. With the reservoir dry, the inspection could not reveal seepage conditions. The spillway is capable of passing 278% of the routed test flood outflow without overtopping the dam.

Download or read book National Program for Inspection of Non Federal Dams Lower Housatonic River Basin Shelton Connecticut Trap Falls Reservoir Dam CT 00091 Phase I Inspection Report written by CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV. and published by . This book was released on 1978 with total page 81 pages. Available in PDF, EPUB and Kindle. Book excerpt: The dam is a concrete gravity structure with concrete buttresses adjacent to the downstream face of the dam spaced at approximately 18 feet on center. An earthen embankment slopes down from the exposed concrete section at a maximum inclination of 2 horizontal to 1 vertical on the downstream side of the dam. The structure is approximately 1080 feet long and has a maximum height of approximately 48 feet above the old streambed. Outlets consist of a 30 inch cast iron low level line at elevation 172, a 30 inch cast iron transmission main and an 8 inch cast iron service main. The spillway is a 137 foot wide nappe-shaped concrete weir with concrete sidewalls. The area downstream of the dam consists of residential and industrial developments, Connecticut Route 8, and further downstream, urban areas of Stratford. Based upon visual inspections at the site and past performance history, the dam appears to be in good condition. No evidence of structural instability was observed in the concrete section, buttresses or the earthen embankment. However, there are some areas which require attention. Based upon our hydraulic computations, the spillway capacity is 4300 cubic feet per second, which is in excess of 100 percent of the Test Flood. Peak inflow to the reservoir is 2600 cubic feet per second; peak outflow (Test Flood) is 1400 cubic feet per second with the dam maintaining a minimum freeboard of 1.8 feet. It is recommended that the left wingwall adjacent to the spillway be monitored to ascertain whether movement which has occurred to date is continuing.

Download or read book National Program for Inspection of Non Federal Dams Kenmere Reservoir Dam CT 00251 Lower Connecticut River Basin Berlin Connecticut Phase I Inspection Report written by CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV. and published by . This book was released on 1980 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: The dam and dike are judged to be in poor condition. The crest of the dam is in poor condition with large vehicle ruts. A deep hole on the crest was observed in the vicinity of the service bridge. No movement or settlement of the crest was indicated and the vertical and horizontal alignment was generally good. The riprap on the upstream face has many gaps leaving the embankment unprotected. Numerous tree stumps were observed on the upstream face. The slopes are extensively overgrown with brush, grass and large trees. The downstream slope has an undulating surface in many locations. A considerable wet area is located along the downstream toe. Numerous small streams were noted carrying water from seeps eminating on the downstream face. The spillway is in very poor condition. The dike's upstream face is unprotected. Extensive vegetation and stumps exist on the upstream and downstream slopes. A large erosion gully approximately four feet deep has formed on the downstream slope. Seepage is evident along the majority of the downstream toe. A small scarp was observed along the downstream toe probably due to continued seepage. A small boil was observed approximately 20 feet downstream of the toe. The capacity of the spillway is inadequate to pass the one half PMF test flood outflow of 3206 CFS without overtopping the dam and dike. The test flood would overtop the dam by about 0.2 feet. The spillway is adequate to pass about 84 percent of the test flood outflow without overtopping the dam and dike.

Download or read book National Program for Inspection of Non Federal Dams Rice Reservoir Dam NH 00141 State Number 47 14 Connecticut River Basin Claremont New Hampshire Phase I Inspection Report written by CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV. and published by . This book was released on 1979 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rice Reservoir Dam has a hydraulic height of 48 ft., is 12 ft. wide, and is 980 ft. kong, It is earthen embankment dam, having a reinforced concrete core and a small chute-type spillway. The dam is in fair condition. It is intermediate in size with a significant hazard potential. Keywords include: Visual inspection, Dam safety, Connecticut River Basin, Claremont, New Hampshire, and Stevens Brook.

Download or read book National Program for Inspection of Non Federal Dams Killingworth Reservoir Dam CT 00401 Connecticut Coastal River Basin Killingworth Connecticut Phase I Inspection Report written by CORPS OF ENGINEERS WALTHAM MA NEW ENGLAND DIV. and published by . This book was released on 1979 with total page 95 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 560 foot long dam is an earth embankment with a masonry and concrete corewall. The top of the dam is 10 feet wide and, at elevation 299, is roughly 29 feet above the streambed of an unnamed tributary to the Menunketesuck River. Upstream and downstream slopes are at two horizontal to one vertical and three horizontal to one vertical inclinations, respectively. A stone filter and underdrain runs along the downstream toe of the dam on both sides of the spillway. The 40 foot wide spillway may be described as a broadcrested concrete weir of trapezoidal cross-section. The concrete spillway wingwalls were extended vertically and horizontally by means of gabions when the downstream slope was flattened in 1973. The channel bottom below the concrete spillway apron is lined with gabions, as are the channel sides. There is also a 16 inch diameter low level outlet pipe and a 6 inch diameter low level outlet pipe through the dam from the concrete intake structure to the downstream channel. There is also a 16 inch diameter low level outlet pipe which runs directly from the reservoir through the intake structure and dam to the downstream channel. Based upon the visual inspection at the site and its past performance, the dam appears to be in good condition. No evidence of instability was observed in the dam or it appurtences. There are some areas of seepage requiring monitoring. Based upon our hydraulics computations, the spillway capacity is 920 cubic feet per second (cfs), which is equivalent to 36 percent of the routed Test Flood outflow.