The Brew Cabin

Tony,
First I'd like to say that this is a great site, well structured nicely laid out, informative and helpful. I wish more web-sites were so good.

I have a question that I could not find the answer to on the site but forgive me if I missed it and maybe just point me in the right direction.

I am considering laying some land drainage and seemingly only have the option of connecting it into a combined foul and surface water sewer.

Your site states that I must put in a vented trap but I cannot find reference on how to do this.

I may have the choice (assuming that both options are feasable) of connecting into either an existing inspection chamber or into a surface water drain. Can you say what would be best and what kind of connections/traps I should use for each option.

Thanks in advance.

Dave

For connection to a combined or foul sewer, you need a trap of some form. I can't trace the reference to a "vented trap" - which page is it on? The trap doesn't actually need venting except under very, very special circumstances.

A simple low-back P-trap would do the job - connect in with a 90 degree knuckle bend, then the P-trap and then the connection to the FW or Combined system. Can you follow that or do you need a sketch?

If you have the choice between connecting to a FW or a SW system, land drainage should always be connected to SW as first choice (assuming there is no ditch/stream etc). Connection to FW is a last resort.

My mistake Tony so appologies - it says via a trap not as I read it, a vented trap. I should read better!

The explaination sounds clear to me so no need for a diagram thanks.

Hope this is not too silly a question but I assume its OK to have the trap buried and inaccessable, or should I be providing access to it somehow?

Again thanks.

Dave

Yes, you should bury the trap but accessibility is something that needs thinking about.

If you're connecting to a SW system (or FW/Combined) you should be able to rod up from some downstream point to the trap. Further, depending on how large an area is being drained by the land drain, a catch pit upstream of the trap may be worth considering, not only to reduce sediment in the sytem, but to provide access for maintenance both downstream to the trap point and back upstream along the drain field.

I wouldn't bother with a catchpit unless I was draining more than 100m2 of silty or sediment-heavy ground or 200m2 of clayey ground.

Thanks for the help Tony - I feel I can get this right now!

Let us know how you get on. :)