Driveway planning application - mistake

[Skiddley]

I've dropped a clanger.

New driveway planning approved last year, alongwith dropped kerb approval from highways.

I included a trench drain+soakaway in plans on front boundary, but also (stupidly) stated that I'd use a porus surface on driveway.

Issue is, the drive will be on a significant gradient (leading down to road), and therefore the porus sub-base + asphalt are not suitable (>~1/20 gradient apparently).

Given that highways have approved the road saftey aspect, no neighbours complained, the design was sound (other than the surface) - is it worth just building the thing with MOT-1 & non-porus asphalt and then applying for retrospective planning?

Worth a conversation with the duty planners first, perhaps? An 8 week delay for revised approval would be an issue.

 

[the_r_sole]

the planners won't care a jot imo - but the roads department will, speak to them about your options first (even if you went back to planning the roads dept would comment on it)
the only real concern would be if you are now in danger of putting excess water onto the main road - they don't like that!

 

[Maccapacca]

The point of planning for driveways now is water run off. I would expect this is a fundemental consideration of the planners and you run the risk of having to do it all again .

 

[Skiddley]

So as mentioned - no water run off as a tranch drain\soakaway will be in place on boundary of drive with footpath.

 

[Maccapacca]

Ask the planners? No one should really be saying it's okay, chuck it in, no one will notice, wing it etc

 

[DB_SamX]

Give the case planning officer a ring to ask. I wouldn't build it without at least knowing that it won't be a problem after.

 

[Skiddley]

So I spoke with the planners. They could not care less about the surface material, it's all about providing adequate drainage to them.

So, going to proceed, build what I need, overspec the drainage and then apply for retrospective.

I've seen a variety of formulas that map from driveway area (90sqm in my case) to the soakaway volume required but I'm looking at between 1.5-2.5m3. Yikes.

Would love to know the official formula if anyone knows it, but will be speaking to the local flood management team who can hopefully advise.

 

[dholdi]

I have found this site to be most useful in the past.

http://www.pavingexpert.com/home.htm

 

[Teknobry]

who's going to know if you build it with slightly different materials as long as your drainage is suitable?

 

[Skiddley]

who's going to know if you build it with slightly different materials as long as your drainage is suitable?

Too many nosey neighbours around here. The planner said he knew were i was so I suspet they'll keep an eye out now for enforcement.

It's cool - I want it above board anyway.

 

[Dave L]

I certainly wouldn't reapply, do the job with the drainage built in and that's it.