Largest Reservoirs in Rhode Island

Rhode Island has 211 dams with recorded storage capacity. The largest is Gainer Memorial with 164,850 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	Gainer Memorial	Providence	164,850	189	Water Supply	1926
2	Diamond Hill Reservoir	Providence	15,680	80	Water Supply	1971
3	Flat River Reservoir	Kent	12,650	24	Recreation	1873
4	Wallum Lake	Providence	10,000	10	Recreation	1866
5	Pascoag Reservoir Upper	Providence	9,000	27	Recreation	1860
6	Watson, Harold E, Reservoir	Newport	7,860	38	Water Supply	1960
7	Moswansicut Pond	Providence	5,750	15	Water Supply	1919
8	Pawtucket Reservoir	Providence	5,300	33	Water Supply	1928
9	Woonsocket Reservoir # 3	Providence	4,740	28	Water Supply	1895
10	Barden Reservoir	Providence	4,320	35	Water Supply	1883
11	Stillwater Reservoir	Providence	3,900	39	Fish and Wildlife Pond	1918
12	Waterman Lake	Providence	3,750	19	Recreation	1837
13	Ponaganset Reservoir	Providence	3,657	26	Water Supply	1865
14	Slatersville Reservoir Upper	Providence	3,640	36		1886
15	James V Turner Reservoir	Providence	3,100	60	Recreation	1934
16	Harris Pond	Providence	2,850	40	Water Supply	1969
17	Nonquit Pond	Newport	1,950	8	Water Supply	1943
18	Georgiaville Pond	Providence	1,950	35	Recreation	1882
19	Horseshoe	Providence	1,935	12	Water Supply	1920
20	Olney Pond	Providence	1,860	30	Recreation	1883
21	Slack Reservoir	Providence	1,780	17	Recreation	1885
22	Lawton Valley Reservoir	Newport	1,764	48	Water Supply	1943
23	Westconnaug Reservoir	Providence	1,620	17	Water Supply	1924
24	Carr Pond	Kent	1,520	8	Recreation	1885
25	Stafford	Newport	1,500	5	Water Supply
26	Tiogue Lake	Kent	1,468	15	Recreation	1875
27	Smith + Sayles Reservoir	Providence	1,450	16	Recreation	1865
28	Easton Pond South	Newport	1,375	13	Water Supply	1876
29	Gardiner Pond	Newport	1,350	20	Water Supply	1885
30	Slatersville Reservoir Middle	Providence	1,330	26		1886
31	St Marys Pond	Newport	1,220	12	Water Supply	1878
32	Almy Reservoir	Providence	1,030	33	Other	1865
33	Bowdish Reservoir	Providence	1,026	14	Recreation	1850
34	Yawgoog Pond	Washington	990	17	Recreation	1885
35	Keech Pond	Providence	870	15	Recreation	1952
36	Coventry Reservoir	Kent	848	15	Recreation	1875
37	Wilson Reservoir	Providence	840	21	Recreation	1866
38	Spring Lake	Providence	840	9	Recreation	1885
39	Indian Lake	Washington	800	12	Recreation	1900
40	Great Swamp Goose Marsh	Washington	770	8	Fish and Wildlife Pond	1960
41	Quidnick Reservoir	Kent	750	14	Recreation	1875
42	Oak Swamp Reservoir	Providence	720	20	Recreation	1865
43	Easton Pond North	Newport	700	14	Water Supply	1891
44	Wincheck Pond	Washington	650	9	Recreation	1885
45	Locustville Pond	Washington	625	18	Hydroelectric	1885
46	Sisson Pond	Newport	550	14	Water Supply	1900
47	Blue Pond	Washington	550	13	Fish and Wildlife Pond	1885
48	Coomer Lake	Providence	510	21	Recreation	1885
49	Arnold Pond	Kent	500	15	Other	1940
50	Curran Upper Reservoir	Providence	500	29	Fish and Wildlife Pond	1902

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