What is a manhole broadstrap?

iceberg twice

I have planning for a 1 off house and have recently sent in a drainage plan to Dublin City Council.

They are insisting I put in place a manhole broadstrap,but I have never heard of it, and my architect is unsure but reckons these were used in days long gone by.

The only info I can find about them (on The net) is people wanting to get them removed because of bad smells but local councils will not do it at there own cost.

Any any info of what these look like?

con1982

Its a u-bend type thing on a manhole. It stops smells and rats from the public sewer from entering the private sewer. They occasionally get blocked, so some people don't like them.

iceberg twice

Thanks Con , wonder if this would hinder the sewerage flow on a short fall?

Busted Flat.

More important it stops toxic gas coming from the main sewer.

con1982

By short fall you mean the slope?

If its domestic try for 1-40 fall, 1-60 can work too, but leaves little room for tolerance.

glencoe

mentioned in another thread.

http://www.boards.ie/vbulletin/showthread.php?t=239686

It is a u-type trap that allows that has a branch to allow rodding when stopper removed it is uasually installed on the downstream side of the last manhole before the main public sewer. As the poster previously said they are very aquard to install and break very easily.

http://www.knowlesdrainage.co.uk/products/productDetail.asp?categoryID=12&subcategoryID=20&parentproductID=714

glencoe

Sorry this is the actual item

http://www.knowlesdrainage.co.uk/products/productDetail.asp?categoryID=12&subcategoryID=20&parentproductID=714

iceberg twice

glencoe wrote: »

Sorry this is the actual item

http://www.knowlesdrainage.co.uk/products/productDetail.asp?categoryID=12&subcategoryID=20&parentproductID=714

Thats a great help Glencoe. By the looks of it I can understand why they give problems and people want them removed. What i dont understand is why the council would insist on one.

I presume you fit it on entry into the manhole and for taking sink waste only, as I can only see blockages if this was to serve toilets?

glencoe

The idea is that it acts like the trap in a toilet and stops smells and vermin coming fack up from the main sewer.
They do need to be cleaned out / checked every year or so. Often the air tight bung which should be in the top socket gets lost and amells etc can pass through over the trap rendering it useless.


http://www.dublincity.ie/WaterWasteEnvironment/WasteWater/Documents/Greater_Dublin_Regional_Code_of_Practice_V6-0.pdf

The right hand details on page 47 show what they want.

Meet with the local drainage dept to see if they will vary he connection. I was allowed to do a backdrop connection in DLRD for a single house.