Dry well overflowing

[drumz]

Just did a remodel and now have a metal roof and also have a drainage system that collects all the water from the downspouts along with drainage around the foundation. This all feeds into a 50 gallon dry well 50 feet from the house. We had quite a downpour the other night and it overflowed out the dry well spout on top and then which created a stream down to my barn flooding it. I live on elevation and don't have an issue flooding a neighbor so my plan is to eliminate the dry well and just let the runoff go down the driveway which will lead it out to the large exposed roadway channel.
The gutters on the house are 5" and all go down the 4" pipe feeding the dry well. I want to reduce the pipe at the dry well down to 3" which will then carry to a 90° opening @ 65' away. This is all on a good slope so there will be no issues of stagnation. Does anyone foresee a problem going down to 3" for the final bit out to the road?
Thanks for your time.

 

[hornetd]

I'm retired out of 40 years of active volunteer fire service. I know that what I'm writing is only tangentially related to your question but I thought that it might possibly be useful to you.

I get a sense that you are out in the country a bit and therefore perhaps beyond the reach of water utility service. If that is true your roof drainage may be an asset. This may be beyond what you are willing to spend but if you can impound some of that water it can serve as a firefighting reservoir. There are a couple of ways to go about that. One would be to excavate and line an underground reservoir that you fill with very course stone or rock. The spaces between the rock would fill with water from your roof. In the bottom of the reservoir you would install a dry hydrant inlet that connects to a fitting that the fire department can use to pump that water on the fire. It is made out of PVC pipe so the only expensive part is the aluminum adapter at the top that will except the fire engines drafting hose.

You would then pipe your overflow out of the top of that reservoir on to were you want the excess to go.

The other technique would be to get a used UBC container

and rig the roof drains to fill it first. You then run 1 inch pex piping to the ceiling or the top of a wall in each room and install an automatic fire sprinkler in that is selected for the ceiling

or wall installation.

The fire sprinklers would be supplied from your regular domestic water supply but if one of them opens a flow detector switch turns on a small electric pump that will substitute water from your UBC container for your domestic water. Since Automatic sprinklers open one at a time, when the temperature a the individual head reaches 130 degrees Fahrenheit, the sprinklers would extinguish the fire with the smallest possible amount of damage. With the exception of persons smoking in bed, who are fatally suffocated before the fire is hot enough to open the sprinkler, the sprinklers will even protect persons who are in the room were the fire started.

Once you learn how to connect the Pex piping installing it is rather easy.

It is just an idea that might be useful to you.

--
Tom Horne

 

[billshack]

you should have calculated the size of the dry well. the area of the roof in square feet X the maximum rain fall in your area in feet ( ie 4 inches is .33 of a foot. this equal the amount of water . that that cubic feet and then triple it because the round river rock with take up at least half the space . if i do this for most houses you are looking at a dry well of several hundred gallon container .

 

[drumz]

you should have calculated the size of the dry well. the area of the roof in square feet X the maximum rain fall in your area in feet ( ie 4 inches is .33 of a foot. this equal the amount of water . that that cubic feet and then triple it because the round river rock with take up at least half the space . if i do this for most houses you are looking at a dry well of several hundred gallon container .

I didn't install it, the people that did my foundation did it and I trusted they knew what they were doing.

 

[slownsteady]

Back to your original question: 3" vs. 4" pipe. If you are going to do that work, why not just lay 4" pipe and not have to worry? But if you already have the 3" pipe, do a little test with a short length and see if it is a problem.....or lay two 3" lines (assuming you have a lot of pipe just sitting around)

 

[billshack]

I didn't install it, the people that did my foundation did it and I trusted they knew what they were doing.

I am a professional , and i really dislike companies that do work that are not qualified , i suggest that you go after this company and make them make it right .

 

[MrMiz]

Tom Horne[/QUOTE] Very good idea.