[TiredDigger]

Hi,

I need advice building a storm drain system. I'm going to dig a trench and run PVC alongside of a long exterior wall where three downspouts deposit water at different points. I will connect those downspouts to the buried piping which will lead to a dry well away from the house. My question is this: if I'm afraid of non-downspout water (so, just rainfall) pooling on the surface in the same area, would it make sense to make that piping perforated and backfill with gravel in order to make a French drain? Or would that defeat the purpose of having the pipes serve as a channel to the dry well for the downspout water (would it exit through the perforations rather than continue to the dry well)?

 

[oh'mike]

Drain pipes should not be perforated-----the idea is to get the water away from the house----

If you want to ALSO gather surface water--add a second pipe with perforations for that purpose.

 

[AllanJ]

If you use a gravel filled trench originating at the house foundation, the trench must be pitched to drain dry even if there was no perforated pipe in it.

Properly pitching the land surface around the house to drain water away on the surface is vastly superior to having a surface level French drain or trench around the foundation.

 

[WhatRnsdownhill]

use solid pipe for the down spouts so you dont fill that pipe with dirt and debris...then to drain ground water use perforated pipe in a gravel bed and they make a special cloth to go over the gravel just over the perforated pipe to keep sediment and debris out of the drain pipe...dig trench pitched away from the house, put in a few inches of gravel lay in pipe, cover with a few more inches of gravel, put down cloth and fill with gravel to ground level or how ever high you want..

 

[Daniel Holzman]

A dry well only works if it is dry. If the groundwater level at the "dry" well is close to the ground level near your house, you cannot drain to the dry well. So before doing a lot of work, you should check the level of high groundwater at the proposed location of the dry well. Simplest way is to install a small pipe, say 2 inch diameter PVC, open at the bottom, into a hole about three feet deep,and measure the water level in the pipe. That will be the groundwater level. Remember that groundwater levels fluctuate, and will typically be highest in the spring.

A lot of people don't want to bother checking groundwater levels, so the alternative is to install the drywell where you think you can drain to it, and take your chances. You may be able to extend the pipe if the drywell proves to be too wet. An alternative is to run the drain pipe out to the street, you may be able to connect to the storm drain system (check with municipality).

 

[TiredDigger]

Thanks for all of the responses. I've decided to go with non-perforated piping to drain the water coming from gutter downspouts. However, I've got a follow up question for y'all. Given Daniel's response, I'm now considering a pop-up emitter rather than a dry-well for several reasons. My question is: what is the max throughput of a pop-up emitter? I intend to have water from three gutter downspouts travel down the drain piping and come out of only one pop-up emitter. Will the one emitter be able to handle water from three downspouts?

Thanks!

 

[Bondo]

My question is: what is the max throughput of a pop-up emitter? I intend to have water from three gutter downspouts travel down the drain piping and come out of only one pop-up emitter. Will the one emitter be able to handle water from three downspouts?

Ayuh,.... Why not just daylight the end of the pipe,..??

Simple, unobtrusive, 'n nothin' to break or malfunction later,....

 

[oh'mike]

Pop up emiters don't work well in areas that freeze, as there is always a pipe full of water---

 

[joecaption]

Just not a good plan to use pop up's they tend to stick and not going to work unless there's a flood of runoff.
Water does not like to run up hill.

 

[TiredDigger]

Bondo, what do you mean by "daylight"? In my neighborhood, breaking the curb and draining to the street is a pain with the permits, fees, tools, and paperwork required -- if that's what you meant.

@Mike, I live in Dallas so I'm not that concerned with freezing temperatures. It happens, but not very often.

 

[TiredDigger]

Bondo, I just looked up what you meant by daylight. My lawn is pretty flat. The slope is enough for the water to flow downwards, but not enough to stick a tube out of the depositing end.

Any other alternatives to a dry-well, pop-up, or daylighting?

 

[Bondo]

Ayuh,.... Even on a low slope lawn, just bring the pipe to the surface, 'n let it drain,.....

At worst, ya might see a 1'x 4" section that can be mowed over,...