diverting water away from house

[Builder]

I put rainwater retention systems in all the time. I like to tie all the downspouts togther into 4 "or preferrably into one 8" solid #40 PVC and run it to a pit. The size of the pit depends on the surface area of the roof. Last one I did was a square 16'x16'x4' deep pit. I run the solid pipe(s) into the pit which is filled with a thin layer of sand on the bottom and then 3" driveway clean stone. But before I install the stone, I "hang" fabric on all 4 sides of the square pit and put a 4' vertical perforated standpipe in the middle that sticks up about 1 foot above the ground with a cap on it. This is so you can check the water level by removing the cap and putting a measuring stick down the pipe. After that, I put in the 3" stone. Then I put a layer of fabric on the stone. Then I dump topsoil on the fabric, rake, seed & straw.

These are mandatory for all new home, garage or addition construction in my area. Takes me about 2-3 days by myself.

Not a great picture, but here's one going in behind my backhoe. Notice the stone I just dumped from my dumptruck:



Here's another one I did for a building back in April:

 

[MarkV]

Builder I am guessing you meant to write 3 foot of gravel rather than 3 inches of gravel. Right?

MarkV

 

[Builder]

Builder I am guessing you meant to write 3 foot of gravel rather than 3 inches of gravel. Right?

MarkV

Actually I think you may have taken me out of context:

I use 3" gravel (meaning stones that are about 3" in size each), not "3 inches of gravel" on the bottom of the pit.

To be more clear, I fill the pit up close to the top with 3" gravel, then cover with the fabric, then put a layer of topsoil, at least 12" on top.

Hopefully that's easier to understand.

 

[bhostasa]

I put rainwater retention systems in all the time. I like to tie all the downspouts togther into 4 "or preferrably into one 8" solid #40 PVC and run it to a pit. The size of the pit depends on the surface area of the roof. Last one I did was a square 16'x16'x4' deep pit. I run the solid pipe(s) into the pit which is filled with a thin layer of sand on the bottom and then 3" driveway clean stone. But before I install the stone, I "hang" fabric on all 4 sides of the square pit and put a 4' vertical perforated standpipe in the middle that sticks up about 1 foot above the ground with a cap on it. This is so you can check the water level by removing the cap and putting a measuring stick down the pipe. After that, I put in the 3" stone. Then I put a layer of fabric on the stone. Then I dump topsoil on the fabric, rake, seed & straw.

These are mandatory for all new home, garage or addition construction in my area. Takes me about 2-3 days by myself.

_____________________________

I've been thinking about doing something similar to this at my house. Couple of questions:

-How far from the house do you typically dig your pit?

-What if the water level was high when you took the cap off? Could anything be done?

I get some water coming up through some cracks in the basement floor on big rains. I've been thinking about putting a drain under the footer and running it out away from the house into a dry pit like you've shown.

 

[Builder]

_____________________________

I've been thinking about doing something similar to this at my house. Couple of questions:

-How far from the house do you typically dig your pit?

I'm pretty sure code in my area says 15' or more, but we have different coades in every township.

-What if the water level was high when you took the cap off? Could anything be done?

If the RWRS is sized correctly, this should never happen, but if it did, you could stick a pump suction hose in it and suck the water out. I actually know some people who suck out the water and tie the discharge end to a hose to water their lawn or garden.

get some water coming up through some cracks in the basement floor on big rains. I've been thinking about putting a drain under the footer and running it out away from the house into a dry pit like you've shown.

Don't run the drain under your footer. It undermines your fotting and if the pipe were to break, it would wash out the soil supporting your footing. Just tie your downspouts together into 6" and run it to a RWRS. That should dry-out your foundation, unless you have springs in the ground, then you need to consider other alternatives. If you must pump out your basement, do it with sump pump pits and discharge lies to a RWRS.

 

[Ken45101]

I've been thinking about putting a drain under the footer and running it out away from the house into a dry pit like you've shown.

Oh no! You would be undermining your footer and then the foundation would probably shift and crack. The lowest I would think you'd want to go is the top of the footer or maybe alongside it (depending on your soil). But in reality, several feet higher would probably intercept the water before it got down that far.

 

[bhostasa]

Oh no! You would be undermining your footer and then the foundation would probably shift and crack. The lowest I would think you'd want to go is the top of the footer or maybe alongside it (depending on your soil). But in reality, several feet higher would probably intercept the water before it got down that far.

Good point. I installed new gutters last fall and that really improved the status of the basement. The old gutters were a bunch of 10' sections so each joint leaked a bit causing a lot of water to sit against the foundation.
the new gutter system is all one piece runs... really helped out.

We only get a little bit of water now on really big rains and it only comes up through the cracks in the floor. We are planning on finishing the basement soon but obviously don't want to invest the $ in that until the moisture issue is completely resolved.

We don't have a sump pump but maybe that would be the easiest way to handle this...

 

[Ken45101]

We don't have a sump pump but maybe that would be the easiest way to handle this...

Sump pumps are great when they are installed in the right system: drain tile around the foundation and a gravel bed under the basement slab so that water can migrate to the pump. Just installing a sump pump without the rest of the system probably won't do much good unless you have really porous ground (we don't, impermeable clay).

Ken

 

[bhostasa]

Sump pumps are great when they are installed in the right system: drain tile around the foundation and a gravel bed under the basement slab so that water can migrate to the pump. Just installing a sump pump without the rest of the system probably won't do much good unless you have really porous ground (we don't, impermeable clay).

Ken

We do have a gravel bed under the slab.

 

[powerstroke444e]

Builder, I thought I was the only one that builts these ??? We do these alot around here with river rock (11/2" to 3" round stone)and the fabric. We also do lots of french tiles like have been discribed. Some have even been tied in to sprinkler systems and livestock watering systems. We have fixed many that have been done wrong but done correctly it does help basements stay dry. We mainly use a walk behind trencher 7 1/2" wide. Then bury plastic 55 gal drums with rock in them to hold them down, I will get photo's on the next one.
To the OP make sure to use a laser when cutting your trench to make sure you have good fall, and I have laid sod on 1/2" of dirt and it worked fine.