Download

11.1 Backslope Drainage Systems, Continued
Criteria
Continued
11.1.3
10/10/03 Draft
• Design and construct interceptor structures in accordance with the
HCFCD Standard Interceptor Structure Detail Sheet in Appendix D.
• Include design details of interceptor structures for pipe sizes larger than
the minimums shown on the HCFCD Standard Interceptor Structure
Detail Sheet in Appendix D.
• Developed property is not allowed to drain to backslope swales, except as
noted below:
• To avoid retaining walls and steep earthen slopes at the back of residential
lots that adjoin a HCFCD maintained facility, one half or less of adjacent
residential lots may be sloped to drain to a backslope drainage system.
• Earthen slopes over six inches high and steeper than 3(H):1(V) are not
allowed adjacent to a backslope swale.
• Where undeveloped acreage drains into the backslope swale system, no
more than 10 acres (15 cfs) can drain into one standard backslope
interceptor structure. If necessary, include additional interceptor structures
and/or larger pipes than the 24 inch minimum to carry the total offsite
flow (submit a drainage area map). Other interceptor structures are
available to collect offsite flow as shown on the HCFCD Standard
Interceptor Structure Detail Sheet in Appendix D.
• Urban interceptor structures can be used in developed areas with limited
right-of-way if HCFCD approval is obtained prior to submitting
construction drawings.
Harris County Flood Control District Policy and Criteria Manual 11-3