Please help me with the specifications for a dry stone drainage pit.

Here's the situation...I am installing 4" perforated drain tile around the entire perimeter of my home. Total of 189 linear feet of tile. Since my home is on a level lot there is no place to "daylight" the drain tile...so my plan is to send the water to a dry drainage pit filled with stone out in the front yard. Right now I have no drain tile and water seepage issues but not any major flooding only seepage during heavy rains. I will be following the proper waterproofing steps for the block walls as well to address any cracks, etc. This discussion is to design where the water needs to go after it is collected by the perimeter perforated drain tile. I don't want to under estimate or over design the size of the pit...please grace me with your knowledge.

Please help me with the details:

How far should I place the pit away from the house?

What should the diameter of the dry pit be?

How much deeper should the bottom of the pit be below where the tile is placed at the foundation? If the foundation drains are at 6 feet deep from grade the pit should be (x) feet deep or (x) feet below the perimeter drain tile grade.

What type of pipe should I use to connect between the perforated perimeter tile and the drain pit? Should it be perforated, solid, etc.? I would think solid smooth pipe would get the water away from the house to the dry stone pit quicker?

How do you protect the stone from dirt? Wrap it all in landscape fabic/filter? Place it into a ADS large diameter pipe of some sort?

I assume the stone does not need to be filled to grade...if not how much stone is adaquate?

Any other details that I need to plan for?

Thank you in advance.

I too would like to learnmore. Anyone give some guidance on a project tlike this?

The problem with trying to calculate a suitable size is that there is no way to tell how much water is going to be transferred using your system. There are a few concerns that I would have in your shoes.

First any pit you make would have to be lower than the draintile you are setting around your perimeter of your house, that is going to be one heck of a deep hole. Secondly, when you back fill with crushed rock then you are greatly cutting down the amount of physical space to be used for water - seems like 80% comes to mind. For instance if you make a hole 10 cubic yards and fill it with crushed rock then you can effectively gather only 2 cubic yards if water in that space. (since 80% of the space is taken with rock).

Third, not only will the water from your system go into this basin, but so will the ground water above during a rain, which again will be too hard to calculate.

So that leaves two options. Build the thing so big that you'll never have to worry about it, or two, put a sump pit in your basement and pump the water out to daylight. This would be my choice because it would be the least risky of the two.