Dalecarlia Reservoir
| Dalecarlia Reservoir | ||
|---|---|---|
Primary inflows Washington Aqueduct | | |
| Basin countries | United States | |
| Surface area | 50 acres (20 ha) | |
| Surface elevation | 148 ft (45 m)[1] | |
Dalecarlia Reservoir is the primary storage basin for
Palisades, two neighborhoods in Northwest Washington, D.C., and Brookmont, a neighborhood in Montgomery County, Maryland
.
History
The 50-acre (200,000 m2) reservoir was completed in 1858 by the
Little Falls Branch until the aqueduct construction was completed. Regular water service from the Potomac River source through the aqueduct commenced in 1864. The reservoir was modified in 1895 and 1935 to improve water quality and increase water supply.[5]
: 75, 99
In the 1920s a water purification plant was built adjacent to the reservoir. The rapid sand filter plant began operation in 1927.[5]: 101–105 [6]
In 1942, the headquarters of the Army Map Service was established on the grounds adjacent to the reservoir; several buildings constructed in the 1940s still exist. In 1946, its headquarters moved to the nearby Sumner Site, which is today the Intelligence Community Campus-Bethesda.[7]
Until the early 21st century, the semi-solid
U.S. Environmental Protection Agency (EPA) required USACE to halt most of these discharges, and a residuals handling facility was built on site, which went into operation in 2012.[8][9]
Current operation
The reservoir and water treatment plant are operated by the Washington Aqueduct, Baltimore District, U.S. Army Corps of Engineers.[10]
Climate
According to the
Köppen Climate Classification system, the area has a humid subtropical climate, abbreviated "Cfa" on climate maps. The hottest temperature recorded at Dalecarlia Reservoir was 105 °F (40.6 °C) on August 17, 1997, while the coldest temperature recorded was −11 °F (−23.9 °C) on January 21, 1985.[11]
| Climate data for Dalecarlia Reservoir, Maryland, 1991–2020 normals, extremes 1948–present | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Record high °F (°C) | 79 (26) |
82 (28) |
91 (33) |
95 (35) |
98 (37) |
100 (38) |
103 (39) |
105 (41) |
99 (37) |
95 (35) |
87 (31) |
82 (28) |
105 (41) |
| Mean maximum °F (°C) | 65.7 (18.7) |
68.0 (20.0) |
77.9 (25.5) |
87.1 (30.6) |
91.9 (33.3) |
96.0 (35.6) |
98.0 (36.7) |
96.6 (35.9) |
92.1 (33.4) |
84.4 (29.1) |
75.3 (24.1) |
67.2 (19.6) |
99.3 (37.4) |
| Mean daily maximum °F (°C) | 42.9 (6.1) |
46.4 (8.0) |
54.8 (12.7) |
67.6 (19.8) |
75.7 (24.3) |
84.0 (28.9) |
88.2 (31.2) |
86.2 (30.1) |
79.4 (26.3) |
68.0 (20.0) |
56.4 (13.6) |
46.9 (8.3) |
66.4 (19.1) |
| Daily mean °F (°C) | 34.2 (1.2) |
36.8 (2.7) |
44.2 (6.8) |
55.6 (13.1) |
64.7 (18.2) |
73.4 (23.0) |
78.1 (25.6) |
76.3 (24.6) |
69.3 (20.7) |
57.4 (14.1) |
46.4 (8.0) |
38.3 (3.5) |
56.2 (13.5) |
| Mean daily minimum °F (°C) | 25.5 (−3.6) |
27.3 (−2.6) |
33.5 (0.8) |
43.6 (6.4) |
53.7 (12.1) |
62.8 (17.1) |
68.0 (20.0) |
66.3 (19.1) |
59.2 (15.1) |
46.8 (8.2) |
36.4 (2.4) |
29.6 (−1.3) |
46.1 (7.8) |
| Mean minimum °F (°C) | 9.2 (−12.7) |
13.2 (−10.4) |
18.5 (−7.5) |
29.0 (−1.7) |
39.2 (4.0) |
50.1 (10.1) |
57.6 (14.2) |
55.3 (12.9) |
45.6 (7.6) |
31.9 (−0.1) |
22.4 (−5.3) |
16.3 (−8.7) |
7.8 (−13.4) |
| Record low °F (°C) | −11 (−24) |
−1 (−18) |
5 (−15) |
17 (−8) |
23 (−5) |
30 (−1) |
42 (6) |
41 (5) |
31 (−1) |
16 (−9) |
8 (−13) |
−2 (−19) |
−11 (−24) |
| Average precipitation inches (mm) | 3.32 (84) |
3.24 (82) |
4.15 (105) |
3.53 (90) |
4.44 (113) |
4.24 (108) |
5.11 (130) |
4.42 (112) |
4.54 (115) |
4.40 (112) |
3.32 (84) |
3.81 (97) |
48.52 (1,232) |
| Average snowfall inches (cm) | 2.9 (7.4) |
1.4 (3.6) |
0.7 (1.8) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.0 (0.0) |
0.8 (2.0) |
5.8 (14.8) |
| Average precipitation days (≥ 0.01 in) | 10.0 | 9.3 | 11.5 | 11.1 | 11.7 | 10.1 | 10.3 | 9.5 | 9.5 | 9.4 | 9.4 | 11.0 | 122.8 |
| Average snowy days (≥ 0.1 in) | 1.5 | 1.1 | 0.5 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | 0.7 | 3.8 |
| Source 1: NOAA[12] | |||||||||||||
| Source 2: National Weather Service[11] | |||||||||||||
See also
References
- ^ U.S. Geological Survey Geographic Names Information System: Dalecarlia Reservoir
- ^ "Washington Aqueduct, District of Columbia, VA and MD; Fact Sheet". Baltimore, MD: U.S. Army Corps of Engineers, Baltimore District. 2023-02-21.
- ^ Proposed Water Treatment Residuals Management Process for the Washington Aqueduct: Environmental Impact Statement. Vol. 1 (PDF) (Report). Washington, D.C.: Washington Aqueduct Division, Baltimore District, U.S. Army Corps of Engineers (USACE). 2005. p. 3-32. Archived from the original (PDF) on 2013-02-16.
- ISBN 9780821413975.
- ^ a b Ways, Harry C. (1996). The Washington Aqueduct: 1852-1992. Baltimore, MD: U.S. Army Corps of Engineers, Baltimore District.
- ISBN 978-0160795572. Publication No. EP 870-1-67. Archived from the originalon 2009-07-22. Retrieved 2023-03-24.
- ^ Horton, Barbara (2004-02-02). "Army Map Service Historic District" (PDF). Maryland Historical Trust. pp. 1–3. Archived (PDF) from the original on 2017-02-03. Retrieved 2019-10-15.
- ^ "Water Treatment Residuals Management Project". Washington Aqueduct. USACE. Retrieved 2023-03-30.
- ^ "Fact Sheet: NPDES Permit No. DC0000019" (PDF). Philadelphia, PA: U.S. Environmental Protection Agency. 2021-04-13.
- ^ "Washington Aqueduct". Baltimore, MD: U.S. Army Corps of Engineers.
- ^ a b "NOAA Online Weather Data – NWS Baltimore". National Weather Service. Retrieved February 20, 2023.
- ^ "U.S. Climate Normals Quick Access – Station: Dalecarlia RSVR, MD". National Oceanic and Atmospheric Administration. Retrieved February 20, 2023.