- Slides: 17
Checkout of Grassed Waterways Beth E. Clarizia, P. E. Agricultural Engineer
Standard Requirements ► Waterways designed to handle a minimum capacity ► Must have a stable outlet ► Flow velocities targeted for a reasonable range, but kept below 5 fps ► When design velocity >3 fps, ECB is required ► Seeding dates: 3/1 5/15 or 8/1 9/30
Checkout Requirements ► Measured constructed length ► Center and low bank shot every 100 feet ► Full cross section every 300 feet
Design • The whole design storm must fit inside the designed flow section, and the velocity when this design section flows full cannot exceed 5 fps.
Cross sections Must show that water drains to the waterway.
Cross sections Can assume a tenth or two of depth of fill along the sides, but be careful.
Survey methods • Use actual, surveyed cross sections and centerline points. Do not interpolate from a generated contour.
Waterway Inlets and Outlets Upstream and downstream ends must: grade out to existing stable ground meet a structure If rock outlet pad is at downstream end, include in waterway checkout
Alternative designs ► Not eligible
Seeding Indicate whether you have done the seeding or not above your signature on the survey notes page If installing ECB, fill out ECB installation report (you should always be confirming seeding if installing ECB)
Rates ► Grassed Waterway = $320 per waterway
Questions ? ? ?