Largest Reservoirs in New Jersey

New Jersey has 408 dams with recorded storage capacity. The largest is Round Valley Dike with 196,600 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	Round Valley Dike	Hunterdon	196,600	80	Water Supply	1961
2	Round Valley South Dam	Hunterdon	196,600	178	Water Supply	1961
3	Round Valley North Dam	Hunterdon	196,600	135	Water Supply	1961
4	Round Valley P&f Dike	Hunterdon	193,000	68	Water Supply
5	Spruce Run Reservoir Dam	Hunterdon	46,770	93	Water Supply	1964
6	Union Lake Dam	Cumberland	20,100	35	Recreation	1869
7	Manasquan Reservoir Dam	Monmouth	18,470	53	Water Supply	1990
8	Oak Ridge Reservoir Dam	Passaic	15,000	60	Water Supply	1892
9	Assunpink #20 Dam	Mercer	14,730	26	Flood Risk Reduction
10	Swimming River Reservoir Dam	Monmouth	14,300	45	Water Supply	1901
11	Lake Mohawk Dam	Sussex	14,220	20	Recreation	1927
12	Lake Tappan Dam	Bergen	13,600	34	Water Supply	1966
13	Clinton Reservoir Dam	Passaic	13,370	56	Water Supply	1894
14	Assunpink # 6 Dam	Mercer	12,653	31	Flood Risk Reduction	1975
15	Point View Dam	Passaic	10,450	55	Recreation	1964
16	Echo Lake Intake Dam	Passaic	7,686	32	Water Supply	1926
17	Echo Lake Spillway Dam	Passaic	7,686	22	Water Supply	1926
18	Lake Lenape Dam	Atlantic	6,610	29	Recreation	1879
19	Canoe Brook Reservoir #3 Dike	Essex	6,000	40	Water Supply	1956
20	Canistear Reservoir Dike	Sussex	6,000	14	Water Supply
21	Yards Creek Lower - Auxiliary Dike	Warren	5,420	35	Hydroelectric	1965
22	Yards Creek Lower - Main Dam	Warren	5,420	55	Hydroelectric	1965
23	Carnegie Lake Dam	Mercer	5,326	28	Recreation	1900
24	Upper Greenwood Lake Dam	Passaic	4,960	20	Recreation	1932
25	Yards Creek Upper - West Dike	Warren	4,900	52	Hydroelectric	1965
26	Yards Creek Upper - East Dike	Warren	4,900	21	Hydroelectric	1965
27	Yards Creek Upper - S. W. Dike	Warren	4,900	25	Hydroelectric	1965
28	Yards Creek Upper - Main Dam	Warren	4,900	70	Hydroelectric	1965
29	Glendola Reservoir Dam	Monmouth	4,330	65	Water Supply	1961
30	Assunpink #4 Dam	Monmouth	4,300	24	Flood Risk Reduction
31	Wildlife Drive Dike	Atlantic	3,827	12	Fish and Wildlife Pond	1959
32	Dundee	Passaic	3,584	16	Hydroelectric	1854
33	Lake Denmark	Morris	3,203	12	Water Supply	1904
34	Farrington Dam	Middlesex	3,140	34	Water Supply	1926
35	Canoe Brook Reservoir #1 Dam	Essex	3,000	25	Water Supply	1929
36	Morris Lake Dam	Sussex	2,985	19	Water Supply	1895
37	Cooper River Parkway (kaighn Ave) Dam	Camden	2,900	15	Flood Risk Reduction	1940
38	Williams Dam	Hunterdon	2,700	22	Fire Protection, Stock, Or Small Fish Pond
39	Cedar Grove South Res Dam	Essex	2,584	51	Water Supply	1903
40	Cedar Grove North Res Dam	Passaic	2,584	51	Water Supply	1903
41	Pines Lake Dam	Passaic	2,530	42	Recreation	1927
42	Mirror Lake Dam	Burlington	2,500	18	Recreation	1880
43	Doughty Pond Dam	Atlantic	2,400	18	Water Supply	1914
44	Canoe Brook Reservoir #2 Dam	Essex	2,200	29	Water Supply	1948
45	Paulinskill Lake Dam	Sussex	2,120	29	Recreation	1927
46	Kuehnle Pond Dam	Atlantic	2,100	14	Water Supply	1935
47	New Jersey No Name # 107 Dam	Burlington	2,100	10	Irrigation
48	Weston Mill Pond Dam	Middlesex	1,965	16	Water Supply	1916
49	Mount Hope Lake Dam	Morris	1,953	18	Recreation	1944
50	Westons Arch Dam	Middlesex	1,600	17	Water Supply	1919

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