Minimum Fall Across Compacted Hardstand
Minimum Fall Across Compacted Hardstand
(OP)
We are designing a central storage 'precinct' for a large farm, to contain sheds, silos, water & chemicals tanks, etc. All of this on a compacted hardstand (in this case it is not feasible to finish the whole area - 7000m² - with bitumen or concrete).
What is the minimum fall we should allow for drainage?
With thanks and kind regards,
Wes
What is the minimum fall we should allow for drainage?
With thanks and kind regards,
Wes
RE: Minimum Fall Across Compacted Hardstand
Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?
-Dik
RE: Minimum Fall Across Compacted Hardstand
Sounds like you're calling the hardstand as impervious for the purposes of storm water quality. In that case, i wouldn't worry too much about minimum slope. I'd worry more about flow velocity and quantity.
Wind and water are the enemy of exposed soil. If not a road or parking, use landscaping to protect the surface. I'd try to grade the road crowned in the middle with 1% slope to each side and 0.56% longitudinal slope. You'd like the road to convey the least amount of water as possible and the slowest velocity possible.
RE: Minimum Fall Across Compacted Hardstand
RE: Minimum Fall Across Compacted Hardstand
I'd want to cover it with SOMETHING - crusher fines, gravel, whatever - that provides some level of drainage.
RE: Minimum Fall Across Compacted Hardstand
The pad is going to be fully regraded and our Civil Engineer has worked out the falls to be workable at 0.5% with 200mm topping of gravel or crushed limestone.
The whole pad (65m wide) will have a continuous fall from west to east where we have a v-drain with large rocks to slow the water down. We considered crowning it in the middle, as KaBone mentioned, but we need to control the runoff to avoid contaminating nearby paddocks, and we also have multiple sheds along the high side at west.
RE: Minimum Fall Across Compacted Hardstand
I'd suggest you make the owner aware of the fact that there's a lot of gravel maintenance in their future if this area is heavy traffic volume, or light volume with heavy farming equipment.