8. The Soils Engineer shall provide a seal depth for the drywells. That seal depth shall be determined by laboratory tests to determine the depth of potential hydrocollappsible soils.
9. Further drywell design information is contained in Section V.F.3 of this document.
H. DEFINITIONS
Natural Watercourses - A natural watercourse is a path along which water flows as a result of natural topographic features. Furthermore, for the purposes of this definition, a natural watercourse drains a watershed greater than 100 acres and also meets one or more of the following conditions:
Experiences flow velocities greater than five feet per second while carrying a Capital Flood.
Has flow depths greater than 1.5 feet while carrying a Capital Flood.
Would have water surface elevations, while carrying a Capital Flood, within one foot of the finished floor elevation of adjacent habitable structures, if such water surface elevations would result from construction of facilities with less than a Capital Flood capacity.
If it is desirable to develop adjacent to a natural creek and leave the creek undisturbed, the following shall be the minimum requirements:
Setbacks: Setbacks shall be determined by flat calculating the area needed to contain the 50 year developed storm, then adding one foot of freeboard. This will define the boundary of the creek. The setback from that boundary shall be determined by projecting an additional ten (10) feet horizontally and from that point a slope of 2:1 until natural ground is intercepted.
Flood area: The area described in the preceding paragraph, including the area for setback, shall be designated as a "FLOOD AREA" on the map.
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