maryland dams

maryland_dams.geojson

{"type":"FeatureCollection","features":[
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-76.6275, 39.392]}, "properties": {"OBJECTID": 1, "State_ID": 346, "National_ID": "MD00304", "Dam_Name": "GBMC Pond", "Other_Dam_Names": null, "Lake_Name": null, "Hazard_Classification": "SIGNIFICANT", "County": "Baltimore", "Latitude": 39.392, "Longitude": -76.6275, "River_or_Stream": "Towson Run-TR", "Dam_Type": "Earth", "Purpose": "Flood Control,Storm Water Management", "Dam_designer": "Daft-Mccune-Walker, Inc", "Year_Completed": "1993", "Year_Dam_Modified": "1993", "Dam_Height": 13, "Normal_Pool_Depth": null, "Dam_Length": 350, "Surface_Area": 0.5, "Normal_Storage": 1.49, "Drainage_Area": 0.078, "Maximum_Storage": 5.4, "Owner_Name": "Greater Baltimore Medical Center", "Operator": null}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-78.938796, 39.575518]}, "properties": {"OBJECTID": 2, "State_ID": 290, "National_ID": "MD00267", "Dam_Name": "Midland-Gilmore Reservoir", "Other_Dam_Names": "Lonaconing Water Treatment Plant No. 3", "Lake_Name": null, "Hazard_Classification": "HIGH", "County": "Allegany", "Latitude": 39.575518, "Longitude": -78.938796, "River_or_Stream": "Elk Lick Run", "Dam_Type": "Earth,Masonry", "Purpose": "Water Supply", "Dam_designer": "Specs, Inc. - Jim Hosken", "Year_Completed": "1903", "Year_Dam_Modified": "1990O", "Dam_Height": 19, "Normal_Pool_Depth": 18.5, "Dam_Length": 229, "Surface_Area": 1.3, "Normal_Storage": 15, "Drainage_Area": 2.2, "Maximum_Storage": 16, "Owner_Name": "Lonaconing Water Co", "Operator": "Miller Environmental, Michael Kesecker"}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-76.452981, 39.674844]}, "properties": {"OBJECTID": 3, "State_ID": 225, "National_ID": "MD00226", "Dam_Name": "Eden Mill Dam", "Other_Dam_Names": "Smith's Mill Dam", "Lake_Name": "Deer Creek", "Hazard_Classification": "SIGNIFICANT", "County": "Harford", "Latitude": 39.674844, "Longitude": -76.452981, "River_or_Stream": "Deer Creek", "Dam_Type": "Gravity", "Purpose": "Recreation", "Dam_designer": "Buchart Horn", "Year_Completed": "1917", "Year_Dam_Modified": "1994SH", "Dam_Height": 18, "Normal_Pool_Depth": 15.4, "Dam_Length": 158, "Surface_Area": 2, "Normal_Storage": 12, "Drainage_Area": 85, "Maximum_Storage": 17, "Owner_Name": "Harford County Parks and Recreation", "Operator": null}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-76.6374, 39.5149]}, "properties": {"OBJECTID": 4, "State_ID": 321, "National_ID": "MD00298", "Dam_Name": "Loveton Farms SWM Facility", "Other_Dam_Names": null, "Lake_Name": null, "Hazard_Classification": null, "County": "Baltimore", "Latitude": 39.5149, "Longitude": -76.6374, "River_or_Stream": "Gunpowder Falls-TR", "Dam_Type": "Earth", "Purpose": "Flood Control", "Dam_designer": "EA Engineering/David Santaro", "Year_Completed": "1985", "Year_Dam_Modified": "1990S", "Dam_Height": 20, "Normal_Pool_Depth": 0, "Dam_Length": 850, "Surface_Area": 0, "Normal_Storage": 0, "Drainage_Area": 0.3, "Maximum_Storage": 39, "Owner_Name": "Baltimore County Deprm", "Operator": "Ba Co Deprm"}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-76.849254, 39.115016]}, "properties": {"OBJECTID": 5, "State_ID": 377, "National_ID": "MD00335", "Dam_Name": "North Laurel Park SWM Pond (Sewall Avenue)", "Other_Dam_Names": "Samuel Morris Dam", "Lake_Name": null, "Hazard_Classification": "SIGNIFICANT", "County": "Howard", "Latitude": 39.115016, "Longitude": -76.849254, "River_or_Stream": "Patuxent River-TR", "Dam_Type": "Earth", "Purpose": "Flood Control,Storm Water Management", "Dam_designer": "Benchmark & Hillis-Carnes Assoc", "Year_Completed": "1998", "Year_Dam_Modified": "1998", "Dam_Height": 30, "Normal_Pool_Depth": 0, "Dam_Length": 270, "Surface_Area": 4.7, "Normal_Storage": 0, "Drainage_Area": 0.3, "Maximum_Storage": 33, "Owner_Name": "Cornerstone Holdings, LLC", "Operator": "Howard Co DPW Stormwater"}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-76.908147, 38.969678]}, "properties": {"OBJECTID": 6, "State_ID": 369, "National_ID": "MD00327", "Dam_Name": "Madison Hill SWM Pond 1 (Silk Tree Drive)", "Other_Dam_Names": null, "Lake_Name": null, "Hazard_Classification": "SIGNIFICANT", "County": "Prince Georges", "Latitude": 38.969678, "Longitude": -76.908147, "River_or_Stream": "Brier Ditch, TR-Northeast Br", "Dam_Type": "Earth", "Purpose": "Flood Control,Storm Water Management", "Dam_designer": "Greenhorne and O'Mara", "Year_Completed": "1994", "Year_Dam_Modified": "1994", "Dam_Height": 18, "Normal_Pool_Depth": 4.7, "Dam_Length": 200, "Surface_Area": 0.5, "Normal_Storage": 1, "Drainage_Area": 0.03, "Maximum_Storage": 4, "Owner_Name": "Prince Georges County", "Operator": "PG Count, Joseph P. Gill"}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-76.8055, 38.5107]}, "properties": {"OBJECTID": 7, "State_ID": 38, "National_ID": "MD00038", "Dam_Name": "Gilbert Run Dam 3 (Jameson Dam)", "Other_Dam_Names": "Gilbert Run Watershed Site #3", "Lake_Name": null, "Hazard_Classification": "HIGH", "County": "Charles", "Latitude": 38.5107, "Longitude": -76.8055, "River_or_Stream": "Gilbert Run", "Dam_Type": "Earth", "Purpose": "Flood Control", "Dam_designer": "USDA SCS", "Year_Completed": "1964", "Year_Dam_Modified": "1964", "Dam_Height": 37, "Normal_Pool_Depth": 21, "Dam_Length": 950, "Surface_Area": 47, "Normal_Storage": 205, "Drainage_Area": 4.3, "Maximum_Storage": 2900, "Owner_Name": "Gilbert Run Watershed Assoc", "Operator": "Charles County DPW"}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-79.0335, 39.5415]}, "properties": {"OBJECTID": 8, "State_ID": 77, "National_ID": "MD00077", "Dam_Name": "Barton Reservoir (Beeman Road)", "Other_Dam_Names": "Barton Pond, Barton Debris Basin", "Lake_Name": "Barton Reservoir", "Hazard_Classification": null, "County": "Allegany", "Latitude": 39.5415, "Longitude": -79.0335, "River_or_Stream": "Butcher Run", "Dam_Type": "Earth", "Purpose": "Water Supply", "Dam_designer": "USDA SCS", "Year_Completed": "1968", "Year_Dam_Modified": "1977HS", "Dam_Height": 31, "Normal_Pool_Depth": 26.5, "Dam_Length": 250, "Surface_Area": 0.7, "Normal_Storage": 4, "Drainage_Area": 1.3, "Maximum_Storage": 15, "Owner_Name": "Town of Barton", "Operator": "Town of Barton"}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-77.4167, 39.0905]}, "properties": {"OBJECTID": 9, "State_ID": 235, "National_ID": null, "Dam_Name": "Horsepen Branch Dam", "Other_Dam_Names": "Horsepen Branch", "Lake_Name": null, "Hazard_Classification": null, "County": "Montgomery", "Latitude": 39.0905, "Longitude": -77.4167, "River_or_Stream": "Horsepen Branch", "Dam_Type": "Earth", "Purpose": "Recreation", "Dam_designer": "Unknown", "Year_Completed": "1950", "Year_Dam_Modified": "1986S", "Dam_Height": 22, "Normal_Pool_Depth": 20, "Dam_Length": 230, "Surface_Area": 20, "Normal_Storage": null, "Drainage_Area": 2.2, "Maximum_Storage": null, "Owner_Name": "Islamic Saudi Academy", "Operator": null}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-76.655818, 38.7203]}, "properties": {"OBJECTID": 10, "State_ID": 398, "National_ID": "MD00356", "Dam_Name": "Calvert Gateway", "Other_Dam_Names": "Penwick Village", "Lake_Name": null, "Hazard_Classification": "SIGNIFICANT", "County": "Calvert", "Latitude": 38.7203, "Longitude": -76.655818, "River_or_Stream": "Hall Creek-TR", "Dam_Type": "Earth,Other", "Purpose": "Flood Control", "Dam_designer": "Mc Crone, Inc", "Year_Completed": "2000", "Year_Dam_Modified": "2000", "Dam_Height": 16, "Normal_Pool_Depth": 2, "Dam_Length": 200, "Surface_Area": 0.9, "Normal_Storage": 0.45, "Drainage_Area": 0.04, "Maximum_Storage": 4.05, "Owner_Name": "Penwick Village Ltd Partnership", "Operator": null}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-77.6213, 39.5389]}, "properties": {"OBJECTID": 11, "State_ID": 42, "National_ID": "MD00042", "Dam_Name": "Greenbrier State Park Dam & Dike", "Other_Dam_Names": null, "Lake_Name": "Greenbrier Lake", "Hazard_Classification": "HIGH", "County": "Washington", "Latitude": 39.5389, "Longitude": -77.6213, "River_or_Stream": "Little Beaver Creek-TR", "Dam_Type": "Earth", "Purpose": "Recreation", "Dam_designer": "Schnable Engr (repairs); James H. Ludlow Assoc.(Orig. Design)", "Year_Completed": "1965", "Year_Dam_Modified": "1996S", "Dam_Height": 64, "Normal_Pool_Depth": 50.5, "Dam_Length": 445, "Surface_Area": 27, "Normal_Storage": 414, "Drainage_Area": 0.8, "Maximum_Storage": 734, "Owner_Name": "MD DNR-Public Lands, Engineering & Constr-Western", "Operator": "Mary Jo Bartles, Greenbrier SP"}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-79.3994, 39.4133]}, "properties": {"OBJECTID": 12, "State_ID": 44, "National_ID": "MD00044", "Dam_Name": "Little Youghiogheny Site 1", "Other_Dam_Names": "Little Yok #1 (Hospital)", "Lake_Name": null, "Hazard_Classification": "HIGH", "County": "Garrett", "Latitude": 39.4133, "Longitude": -79.3994, "River_or_Stream": "Cherry Glade Run", "Dam_Type": "Earth", "Purpose": "Flood Control", "Dam_designer": "USDA SCS-Broomall, Pa Office", "Year_Completed": "1964", "Year_Dam_Modified": "1988O", "Dam_Height": 33, "Normal_Pool_Depth": 11, "Dam_Length": 375, "Surface_Area": 5, "Normal_Storage": 23, "Drainage_Area": 1.2, "Maximum_Storage": 346, "Owner_Name": "Town of Oakland", "Operator": "Town of Oakland/Mayor"}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-77.037622, 39.024417]}, "properties": {"OBJECTID": 13, "State_ID": 127, "National_ID": "MD00127", "Dam_Name": "Wheaton Branch Storm Water Management", "Other_Dam_Names": "MCDEP Asset No. 11365", "Lake_Name": null, "Hazard_Classification": "HIGH", "County": "Montgomery", "Latitude": 39.024417, "Longitude": -77.037622, "River_or_Stream": "Sligo Creek-TR", "Dam_Type": "Earth", "Purpose": "Flood Control,Storm Water Management", "Dam_designer": "Matz, Childs & Assoc. Inc", "Year_Completed": "1979", "Year_Dam_Modified": "1990H", "Dam_Height": 27, "Normal_Pool_Depth": 0, "Dam_Length": 1174, "Surface_Area": 3.1, "Normal_Storage": 11.3, "Drainage_Area": 1.2, "Maximum_Storage": 196, "Owner_Name": "Montgomery County DEP", "Operator": "Montgomery Co DEP"}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-77.0548, 39.5475]}, "properties": {"OBJECTID": 14, "State_ID": 319, "National_ID": "MD00292", "Dam_Name": "Medford Quarry Wash Pond", "Other_Dam_Names": "LaFarge/Genstar/Medford Quarry Wash Pond", "Lake_Name": null, "Hazard_Classification": "SIGNIFICANT", "County": "Carroll", "Latitude": 39.5475, "Longitude": -77.0548, "River_or_Stream": "Turkeyfoot Run-TR-OS", "Dam_Type": "Earth", "Purpose": "Tailings,Water Supply", "Dam_designer": "Stearns&Wheeler(intake, filter drains);Frederick Ward Assoc(orig)", "Year_Completed": "1988", "Year_Dam_Modified": "2009S", "Dam_Height": 26, "Normal_Pool_Depth": 22.8, "Dam_Length": 700, "Surface_Area": 1.1, "Normal_Storage": 17, "Drainage_Area": 0.01, "Maximum_Storage": 20, "Owner_Name": "Bluegrass Materials Company-Maryland Division", "Operator": "Randy Heckler, Medford Quarry"}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-76.0805, 38.9425]}, "properties": {"OBJECTID": 15, "State_ID": 29, "National_ID": "MD00029", "Dam_Name": "Wye Mills Dam", "Other_Dam_Names": null, "Lake_Name": "Wye Mills Community Lake", "Hazard_Classification": "SIGNIFICANT", "County": "Queen Anne's", "Latitude": 38.9425, "Longitude": -76.0805, "River_or_Stream": "Wye East River", "Dam_Type": "Earth", "Purpose": "Recreation", "Dam_designer": "MD DNR-Fisheries", "Year_Completed": "1682", "Year_Dam_Modified": "1958", "Dam_Height": 20, "Normal_Pool_Depth": 12.3, "Dam_Length": 832, "Surface_Area": 61.5, "Normal_Storage": 302, "Drainage_Area": 10.2, "Maximum_Storage": 1224, "Owner_Name": "MD DNR-Public Lands, Engineering & Constr-Eastern", "Operator": "Friends of Wye Mill, Larry McClelland Larry McClelland, <[email protected]>"}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-76.852248, 39.241607]}, "properties": {"OBJECTID": 16, "State_ID": 284, "National_ID": "MD00263", "Dam_Name": "Centennial Park Dam", "Other_Dam_Names": null, "Lake_Name": null, "Hazard_Classification": "HIGH", "County": "Howard", "Latitude": 39.241607, "Longitude": -76.852248, "River_or_Stream": "Little Patuxent River-TR", "Dam_Type": "Earth", "Purpose": "Recreation,Flood Control", "Dam_designer": "Rummel, Klepper & Kahl", "Year_Completed": "1985", "Year_Dam_Modified": "1985", "Dam_Height": 42, "Normal_Pool_Depth": 24, "Dam_Length": 1025, "Surface_Area": 50, "Normal_Storage": 510, "Drainage_Area": 3.5, "Maximum_Storage": 1519, "Owner_Name": "Howard County Parks Dept", "Operator": "Steve Schwarzman"}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-76.7083, 38.9625]}, "properties": {"OBJECTID": 17, "State_ID": 390, "National_ID": "MD00348", "Dam_Name": "UMSTC Lower Dam (Curie Drive)", "Other_Dam_Names": "Melford Lower Dam (Curie Drive)", "Lake_Name": null, "Hazard_Classification": "SIGNIFICANT", "County": "Prince Georges", "Latitude": 38.9625, "Longitude": -76.7083, "River_or_Stream": "Patuxent River-TR", "Dam_Type": "Earth", "Purpose": "Recreation,Flood Control", "Dam_designer": "Century Engineering", "Year_Completed": "2001", "Year_Dam_Modified": "2001", "Dam_Height": 38, "Normal_Pool_Depth": 23, "Dam_Length": 625, "Surface_Area": 5.5, "Normal_Storage": 68, "Drainage_Area": 0.3, "Maximum_Storage": 129, "Owner_Name": "City of Bowie", "Operator": "City of Bowie DPW"}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-75.602376, 38.325986]}, "properties": {"OBJECTID": 18, "State_ID": 199, "National_ID": "MD00199", "Dam_Name": "Morris Mill Pond (South Division Street)", "Other_Dam_Names": null, "Lake_Name": null, "Hazard_Classification": "HIGH", "County": "Wicomico", "Latitude": 38.325986, "Longitude": -75.602376, "River_or_Stream": "Slab Bridge Creek", "Dam_Type": "Earth", "Purpose": "Recreation,Irrigation", "Dam_designer": "CPJ Associates", "Year_Completed": "1947", "Year_Dam_Modified": "2018HS", "Dam_Height": 11.9, "Normal_Pool_Depth": 7.2, "Dam_Length": 241, "Surface_Area": 11.9, "Normal_Storage": 34, "Drainage_Area": 5.1, "Maximum_Storage": 191, "Owner_Name": "Wicomico County Government-Mark Whitelock", "Operator": "George Malone, WI Co."}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-76.9761, 39.388]}, "properties": {"OBJECTID": 19, "State_ID": 139, "National_ID": "MD00139", "Dam_Name": "Piney Run Dam", "Other_Dam_Names": null, "Lake_Name": "Piney Run", "Hazard_Classification": "HIGH", "County": "Carroll", "Latitude": 39.388, "Longitude": -76.9761, "River_or_Stream": "Piney Run", "Dam_Type": "Earth", "Purpose": "Water Supply,Recreation,Flood Control", "Dam_designer": "USDA SCS/Rummel, Klepper&Kahl", "Year_Completed": "1974", "Year_Dam_Modified": "1974", "Dam_Height": 73, "Normal_Pool_Depth": 54.5, "Dam_Length": 624, "Surface_Area": 298, "Normal_Storage": 6036, "Drainage_Area": 10.4, "Maximum_Storage": 8842, "Owner_Name": "Carroll Co Recreation and Parks", "Operator": "Piney Run Park & Nature Center 1040"}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-76.5007, 39.6328]}, "properties": {"OBJECTID": 20, "State_ID": 31, "National_ID": "MD00031", "Dam_Name": "Little Deer Creek Site 1", "Other_Dam_Names": "Madonna Manor Dam", "Lake_Name": "Cattail Reservoir", "Hazard_Classification": "SIGNIFICANT", "County": "Harford", "Latitude": 39.6328, "Longitude": -76.5007, "River_or_Stream": "Cattail Branch", "Dam_Type": "Earth", "Purpose": "Recreation,Flood Control", "Dam_designer": "USDA SCS", "Year_Completed": "1958", "Year_Dam_Modified": "1958", "Dam_Height": 45, "Normal_Pool_Depth": 16.1, "Dam_Length": 385, "Surface_Area": 3.6, "Normal_Storage": 24, "Drainage_Area": 0.7, "Maximum_Storage": 210, "Owner_Name": "Harford County DPW", "Operator": "Harford Co DPW"}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-76.7367, 39.095]}, "properties": {"OBJECTID": 21, "State_ID": 65, "National_ID": "MD00065", "Dam_Name": "Burba Lake (Roberts Avenue)", "Other_Dam_Names": null, "Lake_Name": "Kelly Pool", "Hazard_Classification": "SIGNIFICANT", "County": "Anne Arundel", "Latitude": 39.095, "Longitude": -76.7367, "River_or_Stream": "Franklin Branch", "Dam_Type": "Earth", "Purpose": "Recreation", "Dam_designer": "Unknown", "Year_Completed": "1917", "Year_Dam_Modified": "1917", "Dam_Height": 16, "Normal_Pool_Depth": 4, "Dam_Length": 600, "Surface_Area": 10, "Normal_Storage": 16, "Drainage_Area": 1.1, "Maximum_Storage": 86, "Owner_Name": "US Army - Ft Meade", "Operator": "Fort Meade,U.S.Army"}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-77.205, 39.16667]}, "properties": {"OBJECTID": 22, "State_ID": 53, "National_ID": "MD00053", "Dam_Name": "Lake Whetstone Dam (Montgomery Village Avenue)", "Other_Dam_Names": null, "Lake_Name": null, "Hazard_Classification": "SIGNIFICANT", "County": "Montgomery", "Latitude": 39.16667, "Longitude": -77.205, "River_or_Stream": "Whetstone Run", "Dam_Type": "Earth", "Purpose": "Recreation,Flood Control", "Dam_designer": "Greenhorne, Omara, Dewberry, Nealon", "Year_Completed": "1966", "Year_Dam_Modified": "1966", "Dam_Height": 36, "Normal_Pool_Depth": 17.3, "Dam_Length": 1000, "Surface_Area": 26.6, "Normal_Storage": 167, "Drainage_Area": 3.3, "Maximum_Storage": 930, "Owner_Name": "Montgomery Village Foundation, Inc.", "Operator": "Montgomery Village Foundation"}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-79.000309, 39.591278]}, "properties": {"OBJECTID": 23, "State_ID": 241, "National_ID": "MD00236", "Dam_Name": "Koontz Run Reservoir Tanks", "Other_Dam_Names": "Lonaconing Water Treatment Plant No. 2", "Lake_Name": null, "Hazard_Classification": "HIGH", "County": "Allegany", "Latitude": 39.591278, "Longitude": -79.000309, "River_or_Stream": "Koontz Run", "Dam_Type": "Tank", "Purpose": "Water Supply", "Dam_designer": "RKK (site and dam removal);Dutchland (Tank)", "Year_Completed": "2015", "Year_Dam_Modified": "2015", "Dam_Height": 21, "Normal_Pool_Depth": 20, "Dam_Length": 115, "Surface_Area": 0.5, "Normal_Storage": 10, "Drainage_Area": 2.4, "Maximum_Storage": 10, "Owner_Name": "Lonaconing Water Co", "Operator": "Miller Environmental, Michael Kesecker"}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-78.9761, 39.6124]}, "properties": {"OBJECTID": 24, "State_ID": 253, "National_ID": "MD00243", "Dam_Name": "Klondike Reservoir No. 1 (Lower)", "Other_Dam_Names": null, "Lake_Name": null, "Hazard_Classification": "LOW", "County": "Allegany", "Latitude": 39.6124, "Longitude": -78.9761, "River_or_Stream": "Woodland Creek", "Dam_Type": "Gravity", "Purpose": "Water Supply", "Dam_designer": "Unknown", "Year_Completed": "1930E", "Year_Dam_Modified": "1993S", "Dam_Height": 10, "Normal_Pool_Depth": 9, "Dam_Length": 80, "Surface_Area": 0.3, "Normal_Storage": 1, "Drainage_Area": 1.6, "Maximum_Storage": 1, "Owner_Name": "Klondyke Community Water Co", "Operator": null}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-79.0109, 39.7041]}, "properties": {"OBJECTID": 25, "State_ID": 9, "National_ID": "MD00009", "Dam_Name": "Frostburg Reservoir", "Other_Dam_Names": "Big Piney Run", "Lake_Name": "Frostburg Reservoir", "Hazard_Classification": "HIGH", "County": "Garrett", "Latitude": 39.7041, "Longitude": -79.0109, "River_or_Stream": "Big Piney Run", "Dam_Type": "Earth", "Purpose": "Water Supply", "Dam_designer": "Whitman, Requardt & Assoc.", "Year_Completed": "1990", "Year_Dam_Modified": "1990HS", "Dam_Height": 46, "Normal_Pool_Depth": 32, "Dam_Length": 1275, "Surface_Area": 110, "Normal_Storage": 1410, "Drainage_Area": 11.9, "Maximum_Storage": 3276, "Owner_Name": "City of Frostburg", "Operator": "Mark Garlitz (cell: 240-580-4169)"}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-76.8908, 39.3767]}, "properties": {"OBJECTID": 26, "State_ID": 3, "National_ID": "MD00003", "Dam_Name": "Liberty Dam", "Other_Dam_Names": null, "Lake_Name": "Liberty Reservoir", "Hazard_Classification": "HIGH", "County": "Baltimore", "Latitude": 39.3767, "Longitude": -76.8908, "River_or_Stream": "North Branch, Patapsco River", "Dam_Type": "Gravity", "Purpose": "Water Supply,Recreation", "Dam_designer": "Abel Wolman", "Year_Completed": "1953", "Year_Dam_Modified": "1953", "Dam_Height": 175, "Normal_Pool_Depth": 132.8, "Dam_Length": 704, "Surface_Area": 3106, "Normal_Storage": 132000, "Drainage_Area": 164, "Maximum_Storage": 177000, "Owner_Name": "Baltimore City DPW Reservoir Section", "Operator": "Watershed Mgr"}},
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{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-76.667119, 39.290422]}, "properties": {"OBJECTID": 624, "State_ID": 624, "National_ID": "MD00624", "Dam_Name": "Gwynns Falls Reclamation", "Other_Dam_Names": "2900 West Baltimore Street", "Lake_Name": null, "Hazard_Classification": "LOW", "County": "Baltimore City", "Latitude": 39.290422, "Longitude": -76.667119, "River_or_Stream": "Offstream-Gywnns Falls", "Dam_Type": "Earth", "Purpose": "Stormwater", "Dam_designer": "KCI Technologies", "Year_Completed": "1950E", "Year_Dam_Modified": "2020", "Dam_Height": 9.5, "Normal_Pool_Depth": null, "Dam_Length": null, "Surface_Area": null, "Normal_Storage": null, "Drainage_Area": null, "Maximum_Storage": null, "Owner_Name": "Potts and Callahan, Inc.", "Operator": null}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-76.857309, 38.894982]}, "properties": {"OBJECTID": 625, "State_ID": 625, "National_ID": "MD00625", "Dam_Name": "Summerfield SWM Pond No. 2", "Other_Dam_Names": null, "Lake_Name": null, "Hazard_Classification": "HIGH", "County": "Prince Georges", "Latitude": 38.894982, "Longitude": -76.857309, "River_or_Stream": "TR-Southwest Branch", "Dam_Type": "Earth", "Purpose": "Stormwater Management -Dry", "Dam_designer": null, "Year_Completed": null, "Year_Dam_Modified": null, "Dam_Height": 15, "Normal_Pool_Depth": 0, "Dam_Length": 445, "Surface_Area": null, "Normal_Storage": 0, "Drainage_Area": 0.2057, "Maximum_Storage": null, "Owner_Name": "Prince Georges County", "Operator": "Joseph Gill"}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-76.865753, 39.108721]}, "properties": {"OBJECTID": 626, "State_ID": 626, "National_ID": null, "Dam_Name": "Walker Branch Dam", "Other_Dam_Names": null, "Lake_Name": null, "Hazard_Classification": "LOW", "County": "Prince Georges", "Latitude": 39.108721, "Longitude": -76.865753, "River_or_Stream": "Walker Branch", "Dam_Type": "Masonry", "Purpose": null, "Dam_designer": null, "Year_Completed": null, "Year_Dam_Modified": null, "Dam_Height": null, "Normal_Pool_Depth": null, "Dam_Length": null, "Surface_Area": null, "Normal_Storage": null, "Drainage_Area": null, "Maximum_Storage": null, "Owner_Name": null, "Operator": null}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-76.802238, 39.27601]}, "properties": {"OBJECTID": 627, "State_ID": 627, "National_ID": "MD00627", "Dam_Name": "Ellicott City Courthouse SWM Dam", "Other_Dam_Names": null, "Lake_Name": null, "Hazard_Classification": "LOW", "County": "Howard", "Latitude": 39.27601, "Longitude": -76.802238, "River_or_Stream": "Sucker Branch-TR", "Dam_Type": "Earth", "Purpose": "Stormwater Management", "Dam_designer": null, "Year_Completed": "2010E", "Year_Dam_Modified": "2010E", "Dam_Height": 20, "Normal_Pool_Depth": 1, "Dam_Length": null, "Surface_Area": null, "Normal_Storage": null, "Drainage_Area": null, "Maximum_Storage": null, "Owner_Name": "MD DGS", "Operator": null}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-77.153484, 39.075749]}, "properties": {"OBJECTID": 628, "State_ID": 628, "National_ID": "MD00628", "Dam_Name": "New Mark Commons Community Lake", "Other_Dam_Names": null, "Lake_Name": null, "Hazard_Classification": "SIGNIFICANT", "County": "Montgomery", "Latitude": 39.075749, "Longitude": -77.153484, "River_or_Stream": "Cabin John Creek", "Dam_Type": "Earth", "Purpose": "Recreation", "Dam_designer": "Greenhorne and O'Mara", "Year_Completed": "1966", "Year_Dam_Modified": "1966", "Dam_Height": 15, "Normal_Pool_Depth": 10, "Dam_Length": 300, "Surface_Area": 3, "Normal_Storage": 30, "Drainage_Area": 0.18, "Maximum_Storage": 50, "Owner_Name": "New Mark Commons Assn Inc", "Operator": null}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-77.693764, 39.634195]}, "properties": {"OBJECTID": 629, "State_ID": 629, "National_ID": "MD00629", "Dam_Name": "MKS Stormwater Pond", "Other_Dam_Names": null, "Lake_Name": null, "Hazard_Classification": "LOW", "County": "Washington", "Latitude": 39.634195, "Longitude": -77.693764, "River_or_Stream": "Antietam Creek-TR", "Dam_Type": "Earth", "Purpose": null, "Dam_designer": null, "Year_Completed": "1990", "Year_Dam_Modified": "1990", "Dam_Height": 15, "Normal_Pool_Depth": null, "Dam_Length": null, "Surface_Area": null, "Normal_Storage": null, "Drainage_Area": null, "Maximum_Storage": null, "Owner_Name": "MKS Development Co", "Operator": null}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-76.738348, 39.281773]}, "properties": {"OBJECTID": 630, "State_ID": 630, "National_ID": "MD00630", "Dam_Name": "Banneker Regional Pond", "Other_Dam_Names": null, "Lake_Name": null, "Hazard_Classification": "SIGNIFICANT", "County": "Baltimore", "Latitude": 39.281773, "Longitude": -76.738348, "River_or_Stream": "West Branch Herbert Run", "Dam_Type": "Earth", "Purpose": "Stormwater Management - Dry", "Dam_designer": null, "Year_Completed": "2006", "Year_Dam_Modified": "2006", "Dam_Height": 15, "Normal_Pool_Depth": 0, "Dam_Length": null, "Surface_Area": 0, "Normal_Storage": 0, "Drainage_Area": null, "Maximum_Storage": 15, "Owner_Name": "Baltimore County DEPRM", "Operator": null}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-77.233072, 39.607171]}, "properties": {"OBJECTID": 631, "State_ID": 631, "National_ID": "MD00631", "Dam_Name": "Mehring Culvert", "Other_Dam_Names": null, "Lake_Name": null, "Hazard_Classification": "SIGNIFICANT", "County": "Carroll", "Latitude": 39.607171, "Longitude": -77.233072, "River_or_Stream": "Big Pipe Creek-TR", "Dam_Type": "Earth", "Purpose": "Other", "Dam_designer": "No engineer", "Year_Completed": "1975E", "Year_Dam_Modified": "1975", "Dam_Height": 30, "Normal_Pool_Depth": 0, "Dam_Length": 500, "Surface_Area": null, "Normal_Storage": null, "Drainage_Area": null, "Maximum_Storage": null, "Owner_Name": "Charles Upton Mehring", "Operator": null}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-76.654503, 39.475606]}, "properties": {"OBJECTID": 632, "State_ID": 633, "National_ID": "MD00633", "Dam_Name": "Warren Road", "Other_Dam_Names": null, "Lake_Name": null, "Hazard_Classification": "LOW", "County": "Baltimore", "Latitude": 39.475606, "Longitude": -76.654503, "River_or_Stream": "Goodwin Run", "Dam_Type": "Earth", "Purpose": "Stormwater", "Dam_designer": "DCI Consulting Engineers", "Year_Completed": "1993", "Year_Dam_Modified": null, "Dam_Height": 7, "Normal_Pool_Depth": 0, "Dam_Length": 360, "Surface_Area": 0, "Normal_Storage": 0, "Drainage_Area": 0.005531, "Maximum_Storage": 1.28, "Owner_Name": "MdTA-MD Transportation Authority", "Operator": null}},
{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-77.092667, 39.273719]}, "properties": {"OBJECTID": 633, "State_ID": 632, "National_ID": "MD00632", "Dam_Name": "Herman Dunst", "Other_Dam_Names": null, "Lake_Name": null, "Hazard_Classification": "LOW", "County": "Howard", "Latitude": 39.273719, "Longitude": -77.092667, "River_or_Stream": "Patuxent River 1", "Dam_Type": "Earth", "Purpose": "Irrigation", "Dam_designer": "NRCS", "Year_Completed": null, "Year_Dam_Modified": null, "Dam_Height": 18.8, "Normal_Pool_Depth": null, "Dam_Length": 250, "Surface_Area": 0.5, "Normal_Storage": 2.3, "Drainage_Area": 0.064063, "Maximum_Storage": null, "Owner_Name": "Herman Dunst", "Operator": "Herman Dunst"}}
]}

via https://mdewin64.mde.state.md.us/arcgis/rest/services/DamSaftey/MD_Dams/MapServer