Reservoir report

Delaware reservoirs & dams

Every documented dam and reservoir in Delaware — with normal storage capacity, dam height, max discharge, hazard classification, and drainage area. Sourced from USACE NID and state water-resource agencies.

Dams in Delaware
83
Total storage
32,250ac·ft
High-hazard dams
57
Updated
May 18
Open the Delaware reservoir layer on the map Every dam and reservoir filtered to Delaware on the interactive map.
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May
18
2026
Reservoir report
Delaware only has a few small reservoirs and dams, with the largest being the Hoopes Reservoir, which provides drinking water to the city of Wilmington. Other small reservoirs include the Killens Pond and Lums Pond. These reservoirs are fed by streams and creeks such as the Red Clay Creek and White Clay Creek. Snowpack and mountainous areas are not relevant in Delaware's hydrology, as the state is relatively flat. The region experiences a humid subtropical climate with hot summers and mild winters. There have been occasional drought conditions, such as in 2016 when Delaware experienced a moderate drought. Overall, the state's water supply is considered sufficient and reliably meets the needs of the population.
Delaware at a glance

Storage, hazard, and history

How the Delaware dam inventory breaks down -- aggregate stats computed across every documented dam in the state.

Hazard classification

  • High57
  • Significant9
  • Low17

USACE downstream-consequence rating, not failure likelihood.

Notable dams

  • Tallest Newark Reservoir Dam 51 ft
  • Oldest Brandywine Creek Dam No. 9 1800
  • Total storage All Delaware dams 32,250 ac·ft

Built by decade

Most U.S. dams were built mid-20th century during the federal water-development era.

Full inventory

Delaware dams & reservoirs

Every documented dam in Delaware. Sortable by any column; quickly filterable by name. Numeric columns heat-mapped from light to deep based on value. Tap any dam for the full report.

83 dams
Name Year built Normal storage Dam height Max discharge Hazard Drainage area
Bellevue Lake Dam 1933 126 15 93 High 2
Edgemoor Reservoir Dam 1908 0 13 · High 0
Porter Reservoir Dam 1909 103 12 18 High 0
Edgar M. Hoopes Dam 1932 6,730 · 2,668 High 2
Red Mill Pond Dam 1925 218 12 636 High 7
Trap Pond Dam 1938 3,983 14 3,100 High 16
Millsboro Pond Dam 1920 0 15 1,190 High 62
Trussams Pond Dam · 476 12 633 Significant 14
Ingram Pond Dam · 0 12 640 High 17
Gordons Pond Dam 1967 0 7 26 Low 1
Horseys Pond Dam 1956 689 19 969 High 17
Hudson Pond Dam 1958 151 9 97 Low 5
Fleetwood Pond Dam 1968 102 11 403 High 21
Davis Pond Dam · 38 10 240 Significant 6
Mcginnis Pond Dam · 228 16 2,846 High 8
Duck Creek Pond Dam · 188 9 917 High 18
Lake Como Dam 1938 243 15 1,180 High 6
Masseys Mill Pond Dam 1933 322 12 325 Low 12
Garrisons Lake Dam 1964 840 11 2,740 High 19
Silver Lake Dam - Dover 1944 1,432 17 5,000 High 31
Moores Lake Dam 1967 318 14 2,057 Significant 14
Mudmill Pond Dam · 434 15 1,375 High 54
Wyoming Lake Dam 1925 585 13 2,200 High 11
Voshell Pond Dam 1969 0 14 406 High 8
Derby Pond Dam 1967 93 10 1,437 High 5
Andrews Lake Dam · 89 18 2,202 Significant 6
Coursey Pond Dam 1967 143 20 5,798 High 21
Killen Pond Dam 1969 645 16 1,672 Low 18
Mccauley Pond Dam · 486 19 6,758 Significant 19
Silver Lake Dam - Milford 1964 378 13 5,040 High 27
Haven Lake Dam · 0 17 3,230 High 25
Griffith Lake Dam · 143 13 4,743 High 11
Concord Pond Dam · 1,104 14 7,700 High 63
Brandywine Creek Dam No. 9 1800 0 9 1,933 Low 304
Sunset Lake Dam 1900 300 13 259 High 8
Becks Pond Dam · 140 21 3,700 High 6
Christiana Lake Dam 1907 115 17 9,112 Low ·
Shallcross Lake Dam · 519 8 1,657 Low 6
Noxontown Pond Dam 1966 1,773 14 1,840 Low 10
Silver Lake Dam - Middletown 1931 149 18 2,100 High 7
Wiggins Mill Pond Dam 1965 195 17 1,917 High 5
Abbotts Pond Dam 1960 222 15 787 High 7
Reynolds Pond · 385 11 340 High 7
Chipman Pond Dam 1915 183 14 167 High 17
Swiggetts Pond Dam · 791 12 1,330 High 11
Records Pond Dam 1900 237 25 2,535 High 75
Collins Pond Dam 1922 1,030 11 1,713 Significant 34
Portsville Mill Pond Dam · 73 11 1,303 Low 9
Hearns Pond Dam 1912 1,371 14 2,574 High 13
Wagamons Pond Dam 1815 49 17 5,472 High 22
Burton Pond Dam · 245 10 356 High 9
Williams Pond Dam 1956 0 14 636 High 23
Betts Pond Main Dam · 171 13 696 High 18
Betts Pond Route 113 Dam · 131 10 994 High 17
Morris Millpond Dam 1929 0 10 · Significant ·
Blairs Pond Dam · 129 15 1,076 High 10
City Of Wilmington Sewage Lagoon · 1,213 21 · High 0
City Of Wilmington Sludge Disposal Area · 203 20 · High 0
City Of Laurel Sewage Lagoon 1964 45 13 · High 2
Carousel Pond Dam · 0 36 1,300 High 1
City Of Laurel Sewage Lagoon · 96 15 · High 2
City Of Laurel Sewage Lagoon 1964 96 13 · High 2
Goslee Mill Pond Dam · 27 10 600 Significant ·
City Of Harrington Sewage Lagoon 1971 31 6 · High 0
Clendaniel Pond Dam 1810 279 10 279 High 9
Cubbage Pond Dam 1880 352 11 1,362 High 10
Tailings Pond No. 1 Dam Getty Oil 1960 0 15 · Low ·
Tailings Pond No. 2 Dam Getty Oil 1960 0 15 · Low ·
Tailings Pond No. 3 Dam Getty Oil 1960 180 20 · Low ·
Marshall Millpond Dam · 126 14 550 Significant 7
Diamond Pond Dam · 120 17 90 Low 24
Waples Pond Dam · 0 10 700 Low 15
Canal Farms Dam 1962 75 13 110 Low 1
Cartanza/Ez Farms Dam · 179 7 1,079 High 7
Craigs Pond · 180 14 700 Low 8
Lums Pond Dam · 0 10 380 Low 4
New Castle County Water Farm Wastewater Lagoon · 0 29 · High 1
Newark Reservoir Dam 2005 0 51 180 High 1
Rock Manor Golf Course Dam 2007 0 24 4,522 High 1
Shoals Branch Dam · 206 11 454 High 7
Town Of Middletown Wastewater Lagoon · 293 13 · High 1
Town Of Selbyville Wastewater Lagoon · 0 12 · High 2
Wheatley Pond Dam · 53 8 528 High 3
Reservoir FAQ

About Delaware dams & reservoirs

Where does the Delaware dam data come from?

The U.S. Army Corps of Engineers National Inventory of Dams (NID) plus state water-resource agencies. Snoflo joins these public records with live USGS streamgauge readings downstream where available. The NID is the canonical federal dam registry.

What does Hazard Potential mean?

USACE classifies every dam by what would happen if it failed: Low (no loss of life expected, minimal economic damage), Significant (no loss of life but economic, environmental, or lifeline damage), High (loss of life expected). It's a downstream-consequence rating, not a likelihood of failure.

What is Normal Storage in acre-feet?

The volume of water the reservoir holds at its normal operating level, measured in acre-feet. One acre-foot is about 325,851 gallons or 1,233 cubic meters — the amount needed to cover one acre to a depth of one foot.

Why are some Delaware dams missing storage or height data?

USACE NID records can have gaps for small or older dams that pre-date federal reporting requirements. Snoflo surfaces whatever the canonical record contains. If a dam you care about has incomplete data, contact the operating agency or USACE for updates.

Can I see live water levels?

Yes — tap any dam name to open its detail page, which pulls live storage data from USGS streamgauges or operating-agency feeds where available. Historical levels and seasonal averages are also shown.

Why does Delaware have so many dams?

The U.S. has over 90,000 dams — most built between 1930 and 1980 during the federal water-development era. Delaware's count reflects a combination of agricultural irrigation needs, flood control, hydropower, and recreation. The "Built by decade" chart above shows the timeline.

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