ESRM/FISH 328 Forestry-Fisheries Interactions
Due: 5/25/2012

Road Sedimentation

For the road conditions described below establish the erosion rates with the WEPP program. 

Software:  http://forest.moscowfsl.wsu.edu/fswepp/

Documentation: http://forest.moscowfsl.wsu.edu/engr/forestap/forestap.pdf

The documentation has a number of good schematics that explain some of the road terms

We have one road  in Western Washington (Grays River).  You can get the appropriate climate station from the “Customs Climate” button.

Evaluate sediment generations for the road location for the following conditions using the WEPP software

Road Surface	Gradient	Traffic level	Road design	Soil conditions	Location
Native gravel	4% and 16%	High and none	Insloped, bare ditch Insloped, vegetated or rocked ditch	Sandy loam	Grays Harbor

Road Design		Gradient (%)	Length (ft)	Width (ft)
Insloped, bare ditch  Insloped, vegetated or rocked ditch  Outsloped, rutted  Outsloped, unrutted	Road
	Fill
	Buffer

Road surface: Native Graveled Paved
Traffic level: High Low None

Keep the other parameters the same (road length and width; fill/buffer gradient and length), in other words, only change the road gradient (4% / 16%)

What do you conclude from the results?

• grade (4‐16%),

• road design, bare or rocked/vegetated ditch

• road surface condition

• and especially traffic level on total sediments exported from the road prism