Anyone dealt with flood overlays as part of their planning permit

Hi

Wondering if anyone obtaining their planning permit have had to meet certain conditions relating to overland flooding compliance.

Ie: condition that may include: proposed garage being rejected and replaced with a carport to allow overland flood flows.

Has anyone sought amendment to have a garage roller door permited and if so what proposals did you present in your case to get this over the line

Cheers

 

Yes, it can be done (have done it)
Roller door front and back (but this was because of the flow direction)
Power points 300mm above designated flood level

You will need to drill down past the planners to the internal referral (?) from engineers, or external referral from water authority to find out who made that particular recommendation and then discuss with them
The permit condition will, most likely, have been imposed as a response to someone, other than a planner (most likely) wanting is. You need to find out who, and discuss with them before seeking an amendment - ie go to the source

 

A roller shutter will act as a dam, hold back water until it gives way.

How low below flood levels are you talking? Can you build a bund wall around the garage and ramp up to it? Can you use mesh/vented shutters to allow water to flow through the affected area? Can you reposition the garage so it is not affected to the same extent?

 

Overland flow is usually treated very differently to flooding. Flooding the area fills it up like a bath, putting a roller door in place does not displace water in the flood basin to any perceivable extent. You can often get non habitable rooms with block walls in this sort of area, the basin is large enough to not make much of a difference.

Overland flow is very different. An object placed in the path of water moving through a distinct path in a distinct direction will act as a dam, this can have significant effect on the surrounding property.

Alternate example.

Unit block car parking that is to have an FFL (finished floor level) 500m above NGL (natural ground level)

1. Flood area.
Core filled besser block retaining walls could be used and then the space filled prior to slab being place on top.

2. Overland flow
A suspended slab would need to be used. A hydrologist would need to either:
a. certify that column shape and placement doesn't create a damming effect that would have an impact of significance of upstream properties; or
b. design permanent diversion system so as not to have significant effect.

 

Sorry, I should say yes.
No roller door as it needs t9 be open for that rare flood event.
Our fences need 200mm of mesh at bottom for flood to flow over land through to the next property
So yes bottom 200mm of roller door would need to be open / mesh or something.

Wondering if anyone has examples of going through this and having it approved

How did you manage to get a fully closing roller door - tufa chakir....

 

...I'm an expert in my field and know the rules before I apply. Also get to the bottom of who to discuss the "problem" with. And I don't roll over when a Council planner tells me what I can and cannot do....