Anacostia Watershed Society Homepage

SCA Survey
--Major Problems identified in Northwest Branch--

Northwest Branch watershed - 2
We encourage citizens to visit the sites in person in order to see the damage firsthand. Because the stream changes constantly, it may have features differing from pictures shown on this website. Mouse over the numbers in the map below, then click it to enlarge the picture.

Site # 205109D represents for sites of 205109, 205110, 205111, and205112.

204107 (Exposed Pipe) (N38.9564, W76.9745)

Site #

Date

Location of Pipe

Type

Diameter(in)

Length(ft)

Purpose

Leak from the pipe

204107

2004/12/22

Exposed across bottom of stream

smooth metal

10

60

sewage or water supply

no

This pipe is severely exposed. All exposed pipes should be buried as soon as possible. However, WSSC says they cannot do that. They repair the pipe if it is broken, but they usually don't take preventive action. The pipe material is metal, so it may be a sewer pipe or water supply pipe. Since the pipe is large, I suspect that it is a sewer pipe. The pipe is partially undermined. The diameter is approximately 10 inches. The length exposed is approximately 60 feet.

204110 (Exposed Pipe) (N38.9583, W76.9736667)

Site #

Date

Location of Pipe

Type

Diameter(in)

Length(ft)

Purpose

Leak from the pipe

204110

2005/01/13

Exposed across bottom of stream

concrete

60

100

sewage

no

This exposed pipe was also identified during the past SCA survey on Sligo Creek. The large pipe actually lies across the NWB around the confluence of NWB and Sligo Creek. The exposed pipe WAS a fish barrier but it is not a fish barrier anymore thanks to a restoration effort done by M-NCPPC. Until then, the whole upstream river habitat of NWB and Sligo Creek was separated from the downstream portion of the Anacostia by this exposed pipe. Although this is no longer a fish barrier, it is still an exposed pipe.

Before
SCA survey on Sligo Creek, spring, 2004

After
SCA survey on NWB, Winter, 2005

Diagrammatic Explanation on how the restoration effort works (side view of the stream)

205103 (Erosion Site) (N38.95605, W76.9765833)

Site #

Date

Type

Possible Cause

Length(ft)

Height(ft)

205103

2004/12/22

Widening

Land use change upstream

140

9

This site is severely eroded due to stormwater runoff. The height is about 9 feet, and the length of the erosion site is about 140 feet. The abandoned pipe (picture 205103-1) in the stream is a stormwater pipe. These sites (away from people's eyes) tend to be left out of restoration efforts.

205104 (Erosion Site) (N38.95635, W76.9774333)

Site #

Date

Type

Possible Cause

Length(ft)

Height(ft)

205104

2004/12/22

Widening

Land use change upstream

430

9

A long section of the stream bank is eroded. The approximate length is 430 feet and the approximate height is 9 feet.

205106 (Exposed Pipe) (N38.9566667, W76.9790667)

Site #

Date

Location of Pipe

Type

Diameter(in)

Length(ft)

Purpose

Leak from the pipe

205106

2004/12/22

Exposed across bottom of stream

smooth metal

4

40

sewage

yes

The disconnected pipe in the Picture 205106-1 is away from its original position. One end of it (about 1 foot or more) is buried in the sedimentation indicating the pipe had been discharging for a long period, even months or years. The case was reported to WSSC and repaired temporarily. A permanent repair is expected soon.

This pipe was fixed by WSSC upon AWS' notice.

205110 (Channel Alteration) (N38.9558, W76.9814833)

Site #

Date

Type

Bottom Width(in)

Length(ft)

205110

2004/12/22

concrete

360

3221

Colored section of the stream in the map above was channelized with concrete. This is also a fish barrier since almost no fish can swim in such a shallow stream. Some portions of the stream have an inadequate riparian buffer.

205129 (Trash Dumping) (N38.9519, W76.9847333)

This tributary of NWB has much trash all along the stream. But, this area has much more trash than the other area. The trash comes from Washington, DC. It is very ugly.

205131 (Erosion Site) (N38.95155, W76.9851667)
205132(Exposed Pipe)
205133(Unusual Condision)
Erosion Site

Site #

Date

Type

Possible Cause

Length(ft)

Height(ft)

205131

2005/01/13

Widening

Pipe Outfall

160

12

The maximum height of this erosion site is about 15 feet.

Exposed Pipe

Site #

Date

Location of Pipe

Type

Diameter(in)

Length(ft)

Purpose

Leak from the pipe

205132

2005/01/13

Exposed along stream bank

ceramic

14

52

sewage

no

This is the same location as the erosion site (#205131). At the foot of the eroded bank, a pipe is severely exposed. The day will come soon that the pipe is punctured.

Unusual Condition

After a slight rainfall, a District of Columbia source of Northwest Branch turned brown probably due to sediment discharge from a stormwater pipe (or a buried stream). This is strange to me because DC has Combined Collection system, which collects sewage and rainwater together into a wastewater treatment plant. Theoretically, there should not be any discharge from DC stormwater pipe on dry-weather & light-rain condition.
(Later, it turned out that some portion of the DC employs Separate Sanitary Collection system, which collects sewage separately from stormwater.)

Before
Greenish water: I am not sure if the green color is of algae, phytoplankton, or others

After
After a slight rainfall, the water color changed to brown probably due to sediment discharge. If I were a fish, I would not want to swim in the turbid water.

This water is one of sources of NWB.

Purpose History Gallery Calendar Newsletter Contacts Links Action News

Join AWS Programs River Tours Maps & Directions Virtual Tour Articles Watershed Info

Special thanks to Clair Garman of the Friends of Sligo Creek for his help in editing this page. He is also a member of the Neighbors of Northwest Branch.