Presentation 12:
Vegetated Earth Spillways - Inspection,
Maintenance, and Monitoring

FEMA Workshop - Issues, Remedies and Research Needs Relating to Service and/or Emergency Spillways

Vegetated Earth Spillways
Inspection - Maintenance
&
Monitoring 

Denver, CO
August 26-27,2003

FEMA Workshop - Issues, Remedies and Research Needs Relating to Service and/or Emergency Spillways

OUTLET SECTION – EXIST. AUXILIARY SPILLWAY

FEMA Workshop - Issues, Remedies and Research Needs Relating to Service and/or Emergency Spillways

About 2.5’ of flow with little or no damage

Well maintained dam

FEMA Workshop - Issues, Remedies and Research Needs Relating to Service and/or Emergency Spillways

Spillway Looks like it has been well maintained

Tire Tracks

Equipment used for maintenance destroyed vegetation

FEMA Workshop - Issues, Remedies and Research Needs Relating to Service and/or Emergency Spillways

Trail develops into a major erosion problem.

Erosion in Spillway

Can you see the dam?

Road Up the Spillway

FEMA Workshop - Issues, Remedies and Research Needs Relating to Service and/or Emergency Spillways

Other uses – Trailer in spillway used for a home site

Hp on spillway = 0.5’

Standing in entrance of Aux.
S/W looking at front slope of
Dam – good vegetation

Mud line

FEMA Workshop - Issues, Remedies and Research Needs Relating to Service and/or Emergency Spillways

Standing in entrance of Aux. S/W
Looking upstream – good vegetation

Vegetation in crest no good

Hay bales in control section

Standing in entrance to Aux. S/W looking downstream

FEMA Workshop - Issues, Remedies and Research Needs Relating to Service and/or Emergency Spillways

Almost no vegetation

Standing in control section looking downstream

Control Section

Standing in Aux S/W looking upstream

FEMA Workshop - Issues, Remedies and Research Needs Relating to Service and/or Emergency Spillways




Road

Standing in Exit Channel of Aux. S/W looking upstream

FEMA Workshop - Issues, Remedies and Research Needs Relating 
to Service and/or Emergency Spillways

FEMA Workshop - Issues, Remedies and Research Needs Relating to Service and/or Emergency Spillways

Hickory Creek Site 11 – Hay feeding on control section, cattle working pens in exit section

Vegetation - wrong kind

FEMA Workshop - Issues, Remedies and Research Needs Relating to Service and/or Emergency Spillways

Vegetation – when was the last time the spillway was mowed?

High Hazard Dam

Dam

FEMA Workshop - Issues, Remedies and Research Needs Relating to Service and/or Emergency Spillways

High Hazard Dam

Same Car and House

FEMA Workshop - Issues, Remedies and Research Needs Relating to Service and/or Emergency Spillways

Dam overtopped about 0.5’ and the spillway had about a 5.2’ Hp on it.

5.2’ Hp on crest of this spillway – little or no damage

FEMA Workshop - Issues, Remedies and Research Needs Relating to Service and/or Emergency Spillways

Same spillway after the flow event. Minor damage.

Damage to dam from overtopping – about 0.5’

FEMA Workshop - Issues, Remedies and Research Needs Relating to Service and/or Emergency Spillways

Homogeneous fill??

Spillway with debris from flow event and vegetation

FEMA Workshop - Issues, Remedies and Research Needs Relating to Service and/or Emergency Spillways

Erosion in spillway from a flow event

More erosion from a flow event. Note maintenance and vegetation good.

FEMA Workshop - Issues, Remedies and Research Needs Relating to Service and/or Emergency Spillways

Headcut erosion from flow event.

The End

FEMA Workshop - Issues, Remedies and Research Needs Relating to Service and/or Emergency Spillways