Boggs Mountain Demonstration State Forest Draft ... - Cal Fire

Boggs Mountain Demonstration State Forest Draft Management Plan, June 2008
2. Inslope road surface
3. Clean and maintain ditch relief culverts
4. Excavate outside berm and smooth over roadway
5. Armor outfalls
6. Rock surface
7. Install drainage structures between road and water tank on recreational trail
Site 7: Mile 1.2 to 1.85 (Jct. Rd. 400) (3432 ft.)
Priority: High
There has been significant erosion to the roadway in this section of road. The inboard ditch has
failed or is non-existent. Runoff accumulates and flows down the roadway unimpeded. Drainage
structures (waterbars) have failed in this section and rills and gullies have formed in the roadway.
The road prism is incised and has the effect of a through-cut. Exposed large rocks and boulders
are prevalent throughout this section of road. From mile 1.4 to 1.85, the inboard ditch has failed in
several locations due to sediment deposition and dense vegetation within the ditch. This has
directed runoff onto the roadway and has led to surface erosion. Exposed rock. No ditch or
working waterbars.
Remedial treatments include:
1. Outslope or Crown road
2. Install rolling dips or sharp-angled waterbars
3. Excavate outside berm and smooth over roadway
4. Armor outfalls
5. Import fill to build up roadbed
6. Rock surface
Site 8: Mile 0.0 (Jct. Rd. 400) to 0.35 (1848 ft.)
*note: restart mileage from junction of Road 400 and proceed eastward.
This section of road is insloped with an outside berm and inboard ditch. The berm on the outside
road edge channels surface runoff back onto the roadbed. Even where the road surface is level,
crowned or slightly outsloped, the outside berm prevents free-flow drainage of the road surface.
The inboard ditch has failed in several locations due to sediment deposition and dense vegetation
within the ditch. This has directed runoff onto the roadway and has led to surface erosion. Where
culverts for watercourses cross the road, the inboard ditch should be maintained adjacent to the
stream crossing. Exposed rock.
Remedial treatments include:
1. Outslope or Crown road
2. Install rolling dips
3. Excavate outside berm and smooth over roadway
4. Armor outfalls
5. Rock surface
Site 9: Mile 0.4 to 0.55 (792 ft.)
Priority: High
This section of road is insloped with an outside berm and inboard ditch. At mile 0.45, there is a
cutbank failure approximately 15 feet wide, 40 feet long and 4-6 feet deep. The surface of the
slide has vegetation approx. 5-10 years old covering a portion of the surface. There is no
indication of recent activity, but adjacent cutbank soil may be unstable.
Remedial treatments include:
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