Anacostia Watershed Society Homepage

Erosion is a natural process but apparently the erosion occurring in the Anacostia River is too severe.
As the upstream region of the Anacostia River experiences more housing development, stormwater flushes into the river from the increased impervious surface and consequently annual peak discharge over years is increasing (see the graph shown below).
Since 1939, the amount of discharge has tripled. We need to decrease the amount of this flushing. Incorporation of Low Impact Development (LID) into County code is one of several solutions.

As the upstream portion of NW Branch watershed is developed over years, the impervious surface area increases and the amount of stormwater flushing into stream increases. We need to reduce this amount.

210105 (Exposed Pipe ) (N38.9793667, W76.9660167)

Site#	Date	Location of Pipe	Type	Diameter (in)	Length (ft)	Purpose	Discharge
210105	4/1/2005	exposed across bottom of stream	unknown	20	16	unknown	no

This pipe is in danger of collapse. The pipe could be sewer pipe or natural gas pipe.
It appears to be sewer pipe but there was a sign indicating natural gas pipe in the area.
This case was reported to WSSC asking if this pipe is sewer or not.
In one sense, WSSC and/or Washington Gas are victims of erosion caused by stormwater flushing.

Side View

Front View

210106 (Unusual Condition ) (N38.9791167, W76.9653667)

Gray water indicates pollution. The source of this small stream
flowing into the main stream is the water from stormwater pipe outfall.

211101 (Erosion Site) (N38.9861333, W76.9638167)

Site#	Date	Type	Possible Cause	Length(ft)	Height(ft)
211101	4/1/2005	widening	land use change	120	7

211104 (Exposed Pipe ) (N38.9874, W76.96425)

Site#	Date	Location of Pipe	Type	Diameter (in)	Length (ft)	Purpose	Discharge
211104	4/1/2005	exposed across bottom of stream	concrete	48	98	sewage	no

Large sewer pipe is exposed. This case was reported to WSSC asking to cover it up for protection.
I am not sure if WSSC has taken any action or not for this site but I believe this should be covered as soon as possible. We need preventive action. It is too late if WSSC repairs this after it breaks, after millions of gallons of sewage is discharged. There are good reasons for WSSC to take preventive action.
(1) They get a reputation for good work.
(2) The pipe will have a longer lifetime.
(3) Protecting pipe before it breaks costs less than replacing pipe after it breaks.

The wooden bar is 2 feet long.

Scars from stones washed downstream.

211105 (Erosion Site) (N38.9891333, W76.9667167)

Site#

Date

Type

Possible Cause

Length(ft)

Height(ft)

211105

4/1/2005

widening

land use change

972

6

Very long eroded section of the branch. The length is approximately 972 feet.
Pictures show only portion of it.

211107 (Erosion Site) (N38.9907333, W76.9695333)

Site#	Date	Type	Possible Cause	Length(ft)	Height(ft)
211107	4/1/2005	widening	land use change	897	5

Approximate length: 897 feet. This picture shows only a portion of the site.
My legs were stuck in the SAND by 1.5 feet at several places several times around this stretch.
It is SAND not mud that caught me by my legs. The fact indicates how erosion is severe.
Usually sand deposits gradually and the riverbed consists with sand is steady enough to walk on it.
But because the erosion is so significant, sedimentation occurs so fast making such loose riverbed with sand. Then the sand deposition caught my legs.