Steep (~50%) RCP Storm Drain Installation
Steep (~50%) RCP Storm Drain Installation
(OP)
I'm about to specify a short (~75 l.f.) section of 24" RCP storm drain at a 50% slope. I have unrippable rock, so I've minimized the cover (2.5-ft) and have specified cut-off walls to keep the bedding in place. The storm drain terminates at a manhole with grate (for emergency release)and interior baffle (for energy dissipation) then the water discharges out a drain at 1.0% to a plunge pool and rock-lined channel to its final destination.
Any concerns with this?
Any concerns with this?





RE: Steep (~50%) RCP Storm Drain Installation
RE: Steep (~50%) RCP Storm Drain Installation
How are you going to put the interior baffle in it?
How long is the 1% grade?
RE: Steep (~50%) RCP Storm Drain Installation
im not too concerned with scour. can always reline later.
thanks guys.
RE: Steep (~50%) RCP Storm Drain Installation
RE: Steep (~50%) RCP Storm Drain Installation
Not sure what "unrippable rock" (existing soil conditions?) or "cut-off walls are.
RE: Steep (~50%) RCP Storm Drain Installation
RE: Steep (~50%) RCP Storm Drain Installation
"33.45 High Velocity Protection
Where velocities greater than 15 feet per second (4.6 m/s) are attained, special provision shall be made to protect against displacement by erosion and impact.
33.46 Steep Slope Protection
Sewers on 20 percent slopes or greater shall be anchored securely with concrete, or equal, anchors spaced as follows:
a. Not over 36 feet (11 m) center to center on grades 20 percent and up to 35 percent;
b. Not over 24 feet (7.3 m) center to center on grades 35 percent and up to 50 percent; and
c. Not over 16 feet (4.9 m) center to center on grades 50 percent and over."
See also with regard to cvg's guidance maybe away from RCP for such situations what appears to be (for whatever reasons) a concurring statement on page 372 of the reference at http:
I would also note ductile iron pipes are also sometimes used on steep slopes as they have rather good constructability and toughness e.g. to resist concentrated support reactions etc. (e.g. see http://www