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Clogged Rain Drains?

I just recently moved into a home about three weeks ago. I live in Oregon so we get a considerable amount of rain each year. After a couple of weeks I noticed that water was flowing from the ground about 3 feet away from the end of the garage. Upon further inspection I noticed that there was a cement cap on top of about a 1' to 1.5' diameter, 4' deep cement well that was filled with water and was slowly filling up and spilling onto the drive way.

I thought it may have been a leak in the mainline to the house but I turned the water off at the street and it was still flowing over the top. I was able to look down the pipe and couldn't see any pipes leading into this concret well type structure. I'm just not sure what this could be. Has anyone ever encountered anything like this? I looked into french drains and dry wells but it seems to small to be anything of that sort..

Re: Clogged Rain Drains?

It's probably a 'dry well' and undersized. Finding where the inlet comes from will tell the tale once it dries out. Just run a hose into the gutters and se if water enters. It may also be fed by a sump pump or both. Either way it is inadequate for the job and will need to either have less water going in or be made bigger. You might cut some gutters loose from the system so they will drain above grade and be able to use the existing dry well for the others.


Re: Clogged Rain Drains?

It's more likely a catch basin----you won't know for sure until you remove some of the water & unclog the mud/silt that is now clogging it up so it won't drain properly; catch basins are typically 1 to 3 feet from the bulding, drywells are usually at least 10' away from the building; try to look more closely, there MUST be an entry point somewhere or the unit wouldn't be filling up with water.

The job of a catch basin is to do exactly that---it usually is a collection point for several 2" or 4" drains/downspouts that collect roof water & surface water, that is loaded with shingle bits, plant material, etc.; thus, the catch basin has to be cleaned out periodically.

The catch basin then connects downstream to a buried, larger dry well that collects most of the runoff water; sometimes instead of a drywell, there is a 4" or 6" discharge drain near the street/curbstone to discharge the water out into the street (local codes permitting).

At the first site below, scroll down & click onto black drain photo (p 104) & scroll down to "Building a Dry Well" for a good diagram of a drainage system including roof downspout, catch basin & drywell---these are the essential parts of any runoff drainage system.

Cleaning muck out of a catch basin/drywell is a messy job; if you have a sump pump or motorized pump, you can use that to get most of the water out; wear old clothing & old heavy winter leather gloves or rubber gloves for your hands to remove the silt---do not use bare hands; bits of glass are usually hidden in the mud.

If manually cleaning the catch basin/drywell doesn't get things flowing again, you'll need a stiff metal snake or sewer cleaning service to open the lines again.


Re: Clogged Rain Drains?

Thanks for the help guys, it is supposed to rain here all week but once it drys out a little I will try and see if I can clear out some debris and get the water flowing again. Thanks again!

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