West Thompson Dam, West Thompson, Thompson, Windham County, Connecticut, USAi
| Regional Level Types | |
|---|---|
| West Thompson Dam | Dam (Active) |
| West Thompson | Village |
| Thompson | Town |
| Windham County | County |
| Connecticut | State |
| USA | Country |
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Latitude & Longitude (WGS84):
41° 56' 45'' North , 71° 53' 52'' West
Latitude & Longitude (decimal):
Type:
Dam (Active) - last checked 2025
Köppen climate type:
Nearest Settlements:
| Place | Population | Distance |
|---|---|---|
| Thompson | 9,358 (2017) | 3.2km |
| Putnam | 7,214 (2017) | 3.6km |
| North Grosvenor Dale | 1,530 (2017) | 4.4km |
| South Woodstock | 1,291 (2017) | 5.2km |
| Quinebaug | 1,133 (2017) | 9.6km |
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
Local clubs are the best way to get access to collecting localities
| Club | Location | Distance |
|---|---|---|
| Worcester Mineral Club | Worcester, Massachusetts | 36km |
| Rhe Island Mineral Hunters, Inc. | Warwick, Rhode Island | 48km |
The West Thompson Dam was constructed 1963-1965 by the United States Army Corps of Engineers. It impounds the Quinebaug River for flood control and seasonal storm water management. It enhanced an impoundment already present since at least 1934, as shown in aerial photographs. The new dam is owned and operated by the Corps of Engineers. It is one of the six flood control structures built on the river.
The 200-acre West Thompson Lake has a total storage capacity of 342 million gallons of flood water.
The USACOE project consists of an earthfill dam with stone slope protection 2,550 feet long and 70 feet high; an earthfill dike with stone slope protection measuring 1,650 feet long and 30 feet high; a gated horseshoe shaped concrete conduit 254 feet long and 12 feet in diameter; and a side channel concrete chute spillway with a 320-foot-long L-shaped concrete weir. The weir’s crest elevation is 19 feet lower than the top of the dam.
The origin of the stone used is unknown, but appears to be locally-obtained, dark gray Tatnic Hill Orthogneiss, perhaps from the spillway cut.
Select Mineral List Type
Standard Detailed Gallery Strunz Chemical ElementsDetailed Mineral List:
| ⓘ Calcite Formula: CaCO3 Habit: massive Colour: brown Description: Masses in quartz veins. |
| ⓘ Calcite var. Iron-bearing Calcite Formula: (Ca,Fe)CO3 Habit: Massive Colour: Brown Description: Masses in quartz veins. |
| ⓘ Corundum ? Formula: Al2O3 Description: In a list of minerals for the locality without any supporting information or photos. |
| ⓘ Hematite ? Formula: Fe2O3 Description: Included in a list of minerals for the locality without any supporting information or photos. |
| ⓘ Kyanite ? Formula: Al2(SiO4)O Description: Included in a list of minerals for the locality without any supporting information or photos. |
| ⓘ Magnetite Formula: Fe2+Fe3+2O4 Habit: octahedral Colour: black Description: Thin massive veins and microcrystals associated with ferroan calcite hosted by quartz veins. |
| ⓘ Muscovite Formula: KAl2(AlSi3O10)(OH)2 |
| ⓘ Muscovite var. Fuchsite ? Formula: K(Al,Cr)3Si3O10(OH)2 Description: Included in a list of minerals for the locality without any supporting information or photos. |
| ⓘ Quartz Formula: SiO2 Habit: massive Colour: milky Description: Massive veins hosting masses of brown ferroan calcite. References: Harold Moritz CollectionIdentified by Harold Moritz: Visual Identification |
| ⓘ Rutile ? Formula: TiO2 Description: Included in a list of minerals for the locality without any supporting information or photos. |
| ⓘ 'Scapolite' ? Description: Included in a list of minerals for the locality without any supporting information or photos. |
| ⓘ Schorl ? Formula: NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH) Description: Included in a list of minerals for the locality without any supporting information or photos. |
| ⓘ Tremolite ? Formula: ◻Ca2Mg5(Si8O22)(OH)2 Description: Included in a list of minerals for the locality without any supporting information or photos. |
List of minerals arranged by Strunz 10th Edition classification
| Group 4 - Oxides and Hydroxides | |||
|---|---|---|---|
| ⓘ | Magnetite | 4.BB.05 | Fe2+Fe3+2O4 |
| ⓘ | Corundum ? | 4.CB.05 | Al2O3 |
| ⓘ | Hematite ? | 4.CB.05 | Fe2O3 |
| ⓘ | Quartz | 4.DA.05 | SiO2 |
| ⓘ | Rutile ? | 4.DB.05 | TiO2 |
| Group 5 - Nitrates and Carbonates | |||
| ⓘ | Calcite | 5.AB.05 | CaCO3 |
| ⓘ | var. Iron-bearing Calcite | 5.AB.05 | (Ca,Fe)CO3 |
| Group 9 - Silicates | |||
| ⓘ | Kyanite ? | 9.AF.15 | Al2(SiO4)O |
| ⓘ | Schorl ? | 9.CK.05 | NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH) |
| ⓘ | Tremolite ? | 9.DE.10 | ◻Ca2Mg5(Si8O22)(OH)2 |
| ⓘ | Muscovite var. Fuchsite ? | 9.EC.15 | K(Al,Cr)3Si3O10(OH)2 |
| ⓘ | 9.EC.15 | KAl2(AlSi3O10)(OH)2 | |
| Unclassified | |||
| ⓘ | 'Scapolite' ? | - | |
List of minerals for each chemical element
| H | Hydrogen | |
|---|---|---|
| H | ⓘ Muscovite var. Fuchsite | K(Al,Cr)3Si3O10(OH)2 |
| H | ⓘ Muscovite | KAl2(AlSi3O10)(OH)2 |
| H | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| H | ⓘ Tremolite | ◻Ca2Mg5(Si8O22)(OH)2 |
| B | Boron | |
| B | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| C | Carbon | |
| C | ⓘ Calcite | CaCO3 |
| C | ⓘ Calcite var. Iron-bearing Calcite | (Ca,Fe)CO3 |
| O | Oxygen | |
| O | ⓘ Calcite | CaCO3 |
| O | ⓘ Corundum | Al2O3 |
| O | ⓘ Muscovite var. Fuchsite | K(Al,Cr)3Si3O10(OH)2 |
| O | ⓘ Hematite | Fe2O3 |
| O | ⓘ Kyanite | Al2(SiO4)O |
| O | ⓘ Magnetite | Fe2+Fe23+O4 |
| O | ⓘ Muscovite | KAl2(AlSi3O10)(OH)2 |
| O | ⓘ Quartz | SiO2 |
| O | ⓘ Rutile | TiO2 |
| O | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| O | ⓘ Tremolite | ◻Ca2Mg5(Si8O22)(OH)2 |
| O | ⓘ Calcite var. Iron-bearing Calcite | (Ca,Fe)CO3 |
| Na | Sodium | |
| Na | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| Mg | Magnesium | |
| Mg | ⓘ Tremolite | ◻Ca2Mg5(Si8O22)(OH)2 |
| Al | Aluminium | |
| Al | ⓘ Corundum | Al2O3 |
| Al | ⓘ Muscovite var. Fuchsite | K(Al,Cr)3Si3O10(OH)2 |
| Al | ⓘ Kyanite | Al2(SiO4)O |
| Al | ⓘ Muscovite | KAl2(AlSi3O10)(OH)2 |
| Al | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| Si | Silicon | |
| Si | ⓘ Muscovite var. Fuchsite | K(Al,Cr)3Si3O10(OH)2 |
| Si | ⓘ Kyanite | Al2(SiO4)O |
| Si | ⓘ Muscovite | KAl2(AlSi3O10)(OH)2 |
| Si | ⓘ Quartz | SiO2 |
| Si | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| Si | ⓘ Tremolite | ◻Ca2Mg5(Si8O22)(OH)2 |
| K | Potassium | |
| K | ⓘ Muscovite var. Fuchsite | K(Al,Cr)3Si3O10(OH)2 |
| K | ⓘ Muscovite | KAl2(AlSi3O10)(OH)2 |
| Ca | Calcium | |
| Ca | ⓘ Calcite | CaCO3 |
| Ca | ⓘ Tremolite | ◻Ca2Mg5(Si8O22)(OH)2 |
| Ca | ⓘ Calcite var. Iron-bearing Calcite | (Ca,Fe)CO3 |
| Ti | Titanium | |
| Ti | ⓘ Rutile | TiO2 |
| Cr | Chromium | |
| Cr | ⓘ Muscovite var. Fuchsite | K(Al,Cr)3Si3O10(OH)2 |
| Fe | Iron | |
| Fe | ⓘ Hematite | Fe2O3 |
| Fe | ⓘ Magnetite | Fe2+Fe23+O4 |
| Fe | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| Fe | ⓘ Calcite var. Iron-bearing Calcite | (Ca,Fe)CO3 |
Other Regions, Features and Areas containing this locality
North AmericaContinent
North America PlateTectonic Plate
- Ganderia DomainDomain
- GranderiaPassive Margin
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West Thompson Dam, West Thompson, Thompson, Windham County, Connecticut, USA