Dry well

[joysusan]

I have a walkout finshed basement that I use for an office. I have been putting in a gravel path to the basement door. I dug out the area, put in three inches of crushed limestone, put in a border and then started putting in larger limestone. Before I finished it rained for two days straight. The walk way is on a slope. After the second day, I discovered that about three inches of water had pooled at the bottom of the walk way. The ground slopes gradually away from the walkway, so I dug a ditch and the water drained. I would now like to dig a dry well at the end of the ditch. I could use some advice on how to do that. Thanks.

 

[jdkid]

Hi ya
whats ya house built on ??rock ,clay, sand i have seen them done in poor draining feilds (read as low spots semi ponding) now the one's i have seen are dug bout 2-3 foot round and deep as ya can go filled with stones rock etc etc not to fine better being fist/head size and filled to the top .if well was under ya house might make the place musty (?) any way of pipeing it away .also could be some building laws etc ya may have to look in to. ok reread ya post sounds like it is out side but above info maybe handy a trench filled with rock would do the same thing a few water loveing plants will help use the run off too
catch ya
JD Kid

 

[woodmills1]

i had one at my last house. i dug it 10 ft wide and 30 ft long, filled it with rock, broken blocks, and then stone on top. i put tar paper down before the soil to try to keep it from falling in. i cut the paper to let rainwater drain. now there is geotextile fabric to do the same thing. i drained my sump pump into it, only had some breakout in wet spring weather. one year we called it lake zippy after our cat.

James "woody" Mills

 

[HR_Mutt]

If you have access to a post hole digger for tractor, I've dug some postholes in the spots that hold water, fill them up with stones and then cover them with whatever your surrounding area is, grass, limestone,etc.They work a long time and you don't even know they are there.
regards
Mutt

 

[GlueGuy]

Joy,

My first thought is the same as jdkid. What's your soil type? My second thought is what's beyond, and where do you want the water to go (besides away from the house). My third thought is how much rain do you typically get; untypically too.

You need to size the well based on the amount of rain that you expect it to hold. Then calculate how fast the soil will absorb it. Many times, putting a tile drain might be simpler.

The GlueGuy

 

[joysusan]

The property slopes down south to north. The garage (south side) is at grade. At the north end of the house the entire basement is above ground because of the slope. The path I am contructing runs on the east side (bacK) of the house from the driveway (by the attached garage) to the outside patio that is just outside the basement door. The house is built on clay with rocks to boulders mixed in. This year the rainfall has been strange. It rained for two weeks straight in April and May and then we had a drought all summer. Now it is raining again about every two days. I am going to guess and say the accumulation this week was several inches (I will have to check on that). On Wednesday after an all day steady rain is when I noticed the accumulation of water at the botton of the path by the patio. Because we have an office in the basement and the employees needed to use the walk that day, I dug a drench about 6 feet long, 8 inches wide and 8 inches deep from the path north and away from the house. At the end of the drench, I began digging a hole (I figured the beginning of a dry well) that became 3 feet in diameter and about 2 feet deep. The path not only slopes downward but also lays at an slight angle to the east side - so the water drained out immediately into the trench and then into the hole. However, it is now Saturday, 3 days later, we have not had anymore rain, and the hole is still filled with water (like a very small pond). I suppose this means that I will need a very large drainage area. Also, do I need flexible pipe to drain the area or should I just fill the trench and dry well with large rocks covered with geotextile material (I have some left over from another project). Thanks for your help.

 

[patrickg]

Hello again, JoySusan. The hole you dug (congrats on your enthusiasm) held water too well (pun intended). The larger hole you dig the bigger pond you'll make. Sounds like your soil saturated and has too little percolation. A really big hole with poor percolation just delays the inevitable a little while longer, it fills up and retains water, breeds mosquitos, whatever. Disguised in engineering terms, good surge capacity, slow recovery.

In really really bad cases (yours is beginning to sound like one) you can trench under the path where it stands in water, fill with gravel covered with geotextile topped with gravel to walk on. In the graveled trench you need a perforated drain pipe covered with tyvek sleeving (or similar) to collect the water in the trench and start it down the drain pipe. The drain pipe is to lead the water to where it can be safely and conveniently released. This drain pipe must slope continuoulsy down ward (no loop de loop rollor coaster impromptu "traps" else it will retain water in the "trap(s)", breed mosquitos, and smell bad. It must conltinue "downhill" untill it "breaks" the surface or meets a ditch, storm drain, whatever. The "whatever" could be a better location for a dry well.

Several years ago I had a similar problem in an urban setting. My lot sloped to the rear and drained on to the two down slope neighbors. One took out a raised bed on the fence line and replaced it with a retaining wall (cement) reaching 6-12 inches above grade and I put in an "L" shaped outbuilding with slab floor and a course of block as a stem wall to complete the "dam" across the drainage path. My solution was to dig 3 dry wells. One at each end of the "L" shaped shed and the third under the center of the "L". I ran perforated drainage tubing from the two wells at the extremes to the well in the center. All 4 ends were sleeved in tyvek. The center well was covered by the slab floor. The theory was (and it worked in all conditions for well over 10 years) that any runoff from the driveways, house, and yard that headed down slope in the rear of the house would end up falling down a well (insert smiley face here) and run under the slab of the out building to the well at the center where the water would be discharged essentially where it would have gone had there been no new retaining wall or "L" shaped building.



Patrick (No trees were killed or injured in the preperation of this message.)