The following information was provided by Masaya Maeda of the Anacostia Watershed Society.
AWS has decided to conduct a SCA (Stream Corridor Assessment) survey on the Northwest Branch and has already conducted it on a small portion of the stream. We would like to identify environmental problems such as eroding stream banks, inadequate stream buffers, exposed pipes, altered stream channels, fish migration barriers, pipe outfalls, in-stream construction sites and trash dumping locations along the branch. The major findings will be reported appropriately. The data will be also used to raise people's awareness of stream problems and eventually it will be incorporated into WRAS project by State Government.
Survey Date: 4/14/2005
Site 218103 Comment
One might say, "What is a problem in this picture?" But, there are potential problems.
This picture was taken at a little upstream point from the Burnt Mills Dam.
The dam makes water stagnant and it slows the velocity and reduces turbulence
which would help supply oxygen into the water. These are the potential problems:
- The dam makes stagnant water.
- Once water becomes stagnant, organic matters in the water begins/tend to decay.
- The decaying consumes dissolved oxygen (DO) in the water.
- Decaying increases turbidity.
- Stagnant water is likely to subject water temperature increase easier because of the broader surface, darker water, and so on.
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Site 218110 Unusual Condition
This is not so significant (compared to cases I have ever seen) but algae are emerging.
The brown (orange) matter which covers the river bed is iron.
Site 218112 Exposed Pipe
This pipe is identified as exposed pipe but usually this is not a problem (however, one might say it is esthetically problem)
because it is designed to cross above a stream. However, the supports to the pipe is being undermined and in danger of collapse.
If this happens, the damage to the environment would be significant.
Steven Shofar of WSSC comments regarding this pipe and its supports:
"The trusses that are seen above the sewers were designed to support the sewer independently of the piers
shown in the photographs. The trusses were designed and installed because the piers were failing.
The WSSC does not anticipate any problems with the sewer based on the position of the piers underneath the sewer."
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Site 219103 Exposed Pipe
This stack is in under the pressure from flushing stormwater. The metal lid and rim is vulnerable.
On storm events, the stack gets damage from a flushing stormwater. See the diagrammatic explanation
shown below for the relationship between this stack and the flushing stormwater (see
219104).
Upstream of the flushing stormwater way. It is a little difficult to see from this picture but erosion can be seen.
Site 219106 Unusual Condition
This is another flushing stormwater way.
Bonus Picture
Encountered beaver!
