Largest Reservoirs in Connecticut

Connecticut has 666 dams with recorded storage capacity. The largest is Middle Lanesville Dike with 172,000 acre-feet of maximum storage. One acre-foot equals about 326,000 gallons — enough to supply roughly two households for a year.

#	Dam	County	Max Storage (acre-ft)	Height (ft)	Purpose	Year
1	Middle Lanesville Dike	Litchfield	172,000	45	Hydroelectric	1929
2	Colebrook River Dam - Saddle Dike	Litchfield	134,000	54	Flood Risk Reduction	1969
3	Saville Dam	Litchfield	97,458	137	Water Supply	1940
4	Mansfield Hollow Dam - Dike C	Tolland	76,000	78	Flood Risk Reduction	1952
5	Shepaug	New Haven	72,700	138	Hydroelectric	1955
6	Thomaston Dam	Litchfield	63,000	137	Flood Risk Reduction	1960
7	Lake Gaillard Dam	New Haven	53,500	118	Water Supply	1929
8	West Thompson Dam - Reardon Road Dike	Windham	47,800	19	Flood Risk Reduction	1965
9	Popps Mountain Dike	Fairfield	42,000	36	Water Supply	1941
10	Nepaug East Dike	Hartford	40,540	57	Water Supply	1916
11	Easton Reservoir Dam	Fairfield	36,000	123	Water Supply	1926
12	Drabik Pond Dam	New London	32,000	15	Irrigation
13	Stevenson	Fairfield	26,500	103	Hydroelectric	1919
14	Hop Brook Dam - Saddle Dike	New Haven	23,000	33	Flood Risk Reduction	1968
15	Hall Meadow Brook Flood Control Dam	Litchfield	14,620	75	Flood Risk Reduction	1962
16	Upper Shepaug Dam	Litchfield	13,942	90	Water Supply	1965
17	Compensating Reservoir Dam	Litchfield	13,470	75	Water Supply	1920
18	Hemlock Reservoir Dam	Fairfield	13,300	75	Water Supply	1914
19	Highland Lake Dam	Litchfield	11,800	27	Recreation	1860
20	Mad River Flood Control Dam	Litchfield	11,300	178	Flood Risk Reduction	1963
21	Pachaug Pond Dam	New London	10,962	17	Fish and Wildlife Pond	1888
22	Woodridge Lake Dam	Litchfield	9,800	34	Recreation	1970
23	Rainbow Reservoir Dam	Hartford	9,400	43	Hydroelectric	1925
24	Twin Lakes Dam	Litchfield	9,293	20	Recreation	1900
25	Hancock Brook Dam - Railroad Dike	Litchfield	8,720	51	Flood Risk Reduction	1966
26	Shenipsit Lake Dam	Tolland	8,700	27	Water Supply	1903
27	Goodwin	Hartford	8,532	125	Hydroelectric	1960
28	Trap Falls Reservoir Dam	Fairfield	8,500	48	Water Supply	1905
29	Deep River Reservoir Dam	New London	8,500	62	Water Supply	1926
30	Black Rock Dam	Litchfield	8,450	130	Flood Risk Reduction	1971
31	Samuel Bargh Reservoir Dam	Fairfield	7,515	75	Water Supply	1955
32	Lake Saltonstall Dam	New Haven	6,900	34	Water Supply	1882
33	Mashapaug Pond Dam #3 North	Tolland	6,725	9	Recreation	1900
34	Ellithorpe Flood Control Site #5 Dam	Tolland	5,860	29	Flood Risk Reduction	1968
35	Beach Pond Dam	New London	5,800	12	Recreation	1885
36	Morgan Pond Dam	New London	5,355	45	Water Supply	1966
37	Whiting River Flood Control Dam	Litchfield	5,000	80	Flood Risk Reduction	1968
38	Bashan Lake Dam	Middlesex	4,890	24	Recreation	1939
39	Pistapaug Reservoir Dam	New Haven	4,600	9	Water Supply	1941
40	Columbia Lake Dam	Tolland	4,450	28	Recreation	1865
41	Shelton Canal Dike	Fairfield	4,400	25	Hydroelectric	1870
42	Moodus Reservoir Dam	Middlesex	4,293	18	Recreation	1882
43	Pitch Reservoir Dam	Litchfield	4,200	85	Water Supply	1944
44	Lake Chamberlain Dam	New Haven	4,120	93	Water Supply	1890
45	Ulbrich Reservoir Dam	New Haven	4,090	17	Water Supply	1966
46	Williams Pond Dam	New London	3,993	26	Recreation	1865
47	Broad Brook Reservoir Dam	New Haven	3,850	40	Water Supply	1913
48	Lake Whitney Dam	New Haven	3,600	44	Water Supply	1861
49	Lake Waramaug Dam	Litchfield	3,290	3	Recreation
50	Gardner Lake Dam	New London	3,270	10	Recreation	1900

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