Coquelin Run
From Wikipedia, the free encyclopedia
| Coquelin Run | |
|---|---|
Connecticut Avenue culvert | |
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| Location | |
| State | Maryland |
| County | Montgomery County, Maryland |
| Physical characteristics | |
| Source | |
| • location | Bethesda, Maryland |
| • coordinates | 38°58′57″N 77°05′28″W / 38.9825°N 77.091111°W[1] |
| Mouth | |
• location | Rock Creek |
• coordinates | 38°59′40″N 77°03′47″W / 38.994444°N 77.063056°W |
| Basin size | 1.71 mi2 (4.4 km2) |
| Basin features | |
| River system | Rock Creek |
Coquelin Run is a tributary of Rock Creek in Montgomery County, Maryland. It rises in the Town of Chevy Chase, runs for about two miles while draining an area of 1,095 acres (1.71 square miles), and debouches in Rock Creek in unincorporated Chevy Chase.[2]
While the stream valley remains largely wooded, it has long been affected by nearby urban and suburban development, and its course has been followed for more than a century by railroads and rail trails. From the 1890s to the 1930s, the stream was dammed to power electric streetcars and to create Chevy Chase Lake, an artificial lake that was the centerpiece of a popular trolley park. In the 1920s, a second dam was installed to create a pond on a golf course.
Coquelin Run rises in the Town of Chevy Chase, south of the southern end of Pearl Street and northeast of Elm Street Park, apparently fed by nearby springs or groundwater.[3] It flows eastward for several hundred yards through the back yards of properties along the north and west sides of Elm Street and Oakridge Lane.
Several storm sewers carry water into the stream from nearby Bethesda, particularly a 24" cast-iron outfall just below and south of the Georgetown Branch Interim Trail. On particularly rainy days, the stormwater can exceed the stream's normal flow.[4]
Along the west side of Maple Avenue, the stream runs into a large concrete conduit that ultimately carries it under East-West Highway.[5]
After Coquelin Run emerges north of the road, it enters Columbia Country Club and crosses the southern part of its golf course. A landscaped channel carries it past or through holes 1, 15, 16, 17, and 18; it is dammed at the 17th hole to create a 250-yard-long pond south of the green, where it is joined by one or more unnamed tributaries.[3][6]
After the stream leaves club property, it runs through woods to a culvert under Connecticut Avenue. It collects from two unnamed tributaries as it runs through a wooded, once-dammed valley, and thence to Rock Creek.[3]

