Toe Rock

Toe Rock POLLUTANTS ADDRESSED: Nutrients and Organics, Sediments

-Providing an area for animals to live DESCRIPTION: Toe rock is a layer of rock placed at the base of an eroding stream bank, extending up to bankfull elevation.

It is often used in conjunction with other bioengineering practices.

LOAD REDUCTION MECHANISM: Nutrients/Organics Management- Prevents erosion of organics-rich streambank soils.

Sediment Reduction – Prevents erosion of streambank and sediment production..

LAND USE CLASSIFICATION: Agricultural lands Grazing lands Urban area

ALTERNATIVE MANAGEMENT MEASURES: Brush Trench Brush Revetment Post/Pole Plantings Seeding PERMITTING REQUIREMENTS: Permits are required under Sections 404 and 401 of the Clean Water Act. Contact county regional flood district

ADDITIONAL BENEFITS: Streamside

Arid Southwest BMP

POTENTIAL TREATMENT AREAS:

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Toe Rock POLLUTANTS ADDRESSED: Nutrients and Organics, Sediments

Level 400: MODERATE ENGINEERING LOAD REDUCTION POTENTIAL: Riparian Planting Zone: Toe Zone.

LOW

MEDIUM

HIGH SOURCES OF ADDITIONAL INFORMATION:

ESTIMATED TIME FOR LOAD REDUCTION: IMMEDIATE

MONTHS2 YEARS

TMDL Water Quality Study of the Virgin River Watershed, submitted to Utah Department of Environmental Quality, Division of Water Quality. http://www.waterquality.utah.gov/TMDL/Duchesne_River _Watershed_TMDL.pdf

> 2 YEARS

EXPECTED MAINTENANCE: LOW

MEDIUM

HIGH

ESTIMATED COST: LOW

MEDIUM

HIGH

PLANNING AND IMPLEMENTATION: Toe rock is an armoring technique to provide additional strength to stream banks. A variety of rock sizes can be used but must be designed to withstand stream forces.

The rock is installed in a trench that extends below the stream scour level. Toe rock should not extend above the elevation of the adjacent floodplain. Often a filter fabric is installed behind the rock to keep stream flows from washing out soils behind the structure.

Arid Southwest BMP

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