by siberian tigers. how and where has the removal of the dam physically effected the structure of...

By Siberian Tigers

How and where has the removal of the dam physically effected the structure of the Elwha river?

• Dam removal would result in lower water level

• Lower water level would carry sediments

• Computer with Google Earth

Field Materials:

• Boots, tripods, GPS, Camera + Memory Card, Batteries

1. Pick six sites on Google Earth along the Elwha river with noticeable differences between before the dam was removed and after (Find differences using the time slider)

2. Visit each site and take pictures

3. Analyze structure of the river through pictures taken

Data Point 147.972657°

-123.593665°A river blowout is observed at Cat Creek as it enters the Elwha, possibly because of dam removal. Trees are in

the bottom of the valley.

2009 2012

Data Point 2 47.992657°

-123.600642°This picture of Lake Mills is a good example of the change of the water

level after the dam was removed.

2009 2012

Data Point 347.949093°

-123.558428°The River in 2009 is a curve and now in 2012 it is a straight river. Near

Humes ranch

20122009

Data Point 4 48.080498°

-123.570295°The water level got a lot lower in 2012.

Lake Aldwell

2009 2012

Data Point 548.121043°

-123.556585°Elwha River near the State Fish Hatchery

2009 2012

Data Point 648.145481°

-123.566472°Mouth of the Elwha

2009 2012

We observed that the removal of the dam and the declining water levels in the Elwha river have caused the build-up of sediment at the bottom have been carried down the river and have caused extensive erosion along the river and have overall physically changed the river.

If the sediment at the bottom of the Elwha river gets carried down to the delta there will be a significant change in the structure of the river because the water currents will erode different parts of the banks, and the sediment will build up.

Plan:

• Monitor points for 5 years

• Set up equipment at the 6 points

• Collect data/photos and record results

• Help land managers increase salmon runs

• Help land managers understand how the river affects other habitats, such as forests.