The Brew Cabin

Do I need to demonstrate that soakaways will work and do they need to be inspected by the buildings inspector?.

On my clay site some surface water flows down the gentle slope into a surface water drain in the road. If I build a house I'm not allowed to connect directly to the surface drain but one practical solution would be to locate soakaways so that if/when they overflow the water will continue to flow down the gravel driveway into the drain. The net impact on the drain will be zero but would the buildings inspector put a stop to this if he spotted the scheme?

I may also need to build a cut-off drain (land/french drain) to prevent my foundations causing surface water to go nextdoor. Could consider discharging this down my driveway as well? I don't think the volumes of water involved are very large.

Soakaways for private properties are a bit of a grey area. I know one local authority that simply doesn't want to know about them and lets you get away with almost anything, while the neighbouring authority insists on a percolation test and inspects the pit before passing the drainage to the plot as acceptable.

In areas where soakaways are common, then the BCO is less likely to need convincing of their viability, but if yu;re in a clay spot, then it may be wise to seek the advice of the BCO - they're not there to make your life hell, despite what you might think, but are often a damned useful (and free) source of very good advice and often have years of experience with regard to local conditions.

In your situation, I would discuss your plans with the BCO and see what interpretaion they will put on it. Personally, I wouldn't be happy with the soakaway being designed to surcharge into the gully on the public highway, and the same goes for the interceptor drain you're considering around the foundations.

Have you done a percolation test yourself? How confident are you about the viability of the soakway? Given the push for Sustainable Urban Drainage Schemes (SUDS) in modern developments, it's well worth considering an extra large soakaway facility if you have the right conditions. It's much better for the environment than relying on a public SW system that dumps everything in the local river.

This thead was of interest to me. Last year I put in a perforated pipe land drain system to my back garden and connected it to the end of a run (rodding eye) on the surface water drain. Should I have sought permission and approval to cover up from someone? Oops?

No, you're ok, David, because you are connecting to an existing SW system, whereas cwatters is looking at using a soakaway in place of a connection to the public SW sewer.

On new-build or extensions, the local authority may require proof of the viability of a soakaway before passing the drainage scheme as acceptable. Adding a relatively small amount of land drainage to an existing SW system is nothing to concern them. :)

I've done a bit more research and what I had assumed was a surface water drain is actually a pipe ditch. eg it was an open ditch that was partly covered when the road was made up. Much further down the ditch is stil open.

I've done a lot of ringing round and the local water company say they don't own it (just the seperate foul sewer in the road).

The council say they don't own it but were quite helpful. They told me that they dug out or at least cleaned out the open section of the ditch a while back. They also mentioned that I may have "Riparian" rights (rights to discharge into an adjoining stream/river). Any idea how I confirm this? I guess it's a question for a solicitor?

I've not done my own percolation test yet but the soil is a heavy clay and I've seen a soil condition report that states something like "soakaways are unlikely to work" or "not ideally suited to soakaways". Hence my interest in discharging into this pipe/ditch. On a practical level it should be ok because that's where all the water currently goes.

I'll think I'll speak to the BCO as you suggest.

The LA, as agent for the Water Co will be able to confirm your Riparian rights, but, from what you say, discharging into that culverted ditch would be the best way to go. The BCO might be able to offer more advice, but, if you can't get any sense from the LA about the connection rights, then I'd put in writing your intention to connect and send them a copy by recorded post.

Riparian rights are a bit of a legal minefield - not that they are always contentious, just that they can be a right abstrad to track down, just the sort of work a solicitor loves to assign to the spotty office junior and charge you 75 quid per hour for the privilege. :(

You'll get more sense from the BCO or the Tech Services Dept than you will from a solicitor!

Sorry to seem a bit dim but by 'LA' I assume you mean the Local Authority (eg drainage dept of county council)?

Yes - sorry, but I sometimes forget to switch from Trade Talk to normal English . :)

LA = Local Authority
BCO = Building Control Officer
BM = Builders Merchant
BoQ = Bill of Quantities

...I'm sure there's more! Maybe a page covering all my many acronyms is required? :)