S-10-0296 922_waterbar_std.doc

Section C

Page

Section 922 -- Waterbars

Description

922.01 Work. This work consists of installing waterbars, including excavation, backfill, and outlet drainage; selecting log and rock materials; and furnishing treated timber and other materials where required.

Materials

922.02 Requirements. Use materials meeting the requirements of Section 961.

Construction

922.03 General. Install waterbars at the locations NOTED ON THE TRAIL LOG.

(a) Native Log or Rock Waterbar PAY ITEM. Where suitable rocks are available within 200 feet either direction along the trail, within 100 feet uphill, or within 50 feet downhill, of the waterbar location, the waterbar shall be constructed of rock. Where suitable rocks are not available, use native timber.

922.04 Excavation and Embankment. Perform excavation and embankment in accordance with Section 912. Backfill and compact suitable material around waterbar. Compact material on the downgrade side flush with the top of the waterbar.

922.05 Rock Waterbar. Tightly embed selected rocks into the trailbed. Place waterbar rocks with tops relatively even, with no sharp points. Use rocks with lengths greater than or equal to 1.5 times their width.

922.06 Log Waterbar. Embed peeled native logs or into the trailbed to form a waterbar across the trail. Use anchor methods as SHOWN ON THE DRAWINGS at log or timber ends outside the trail tread. In the absence of a backslope, anchor the upgrade end of the log or timber waterbar in the same manner as the downgrade end.

922.07 Outlet Drainage. Construct outlet ditches where NOTED ON THE TRAIL LOG or as necessary to provide drainage. Where NOTED ON THE TRAIL LOG or where outlet ditches will not drain within 20 feet, construct an 18-inch diameter drain sump to a minimum depth of 24 inches and located at least 5 feet from edge of trailbed. Fill sump with coarse rock.

Measurement

922.08 Method. Measure the quantities in accordance with Section 906.

Payment

922.09 Basis. Pay for the accepted quantities in accordance with Section 906 at the contract unit price for each PAY ITEM SHOWN IN THE SCHEDULE OF ITEMS.

The following will be considered incidental to the PAY ITEMS SHOWN IN THE SCHEDULE OF ITEMS and extra payment will not be given:

Outlet ditches and drain sumps.

Make payment under:

PAY ITEM

PAY UNIT

922(01) Native Log or Rock Waterbar

EA

922(02) Waterbar, Special Diversion. . . . . . . . . . . . . . . . . . . . . . . . EA 922-1 (12/11/2009)