Put in French drain, works great, need advice

[corn18]

I'm thinking it might still be a fast flowing river. Your drain collects the water and fills the basin. The basin fills and then overflows at the rate water is added to it. There will be a delay equal to the time it takes for the basin to fill before the river develops, but it seems that after that pretty much the same thing.

Is it the redirection of the water and/or the time it takes for the water to move from above you, through your yard (via the new drain and pit) and into your neighbor's yard that you're counting on to eliminate the "fast flowing river?"

The basin acts like a reverse nozzle. The water coming out of the 4" pipe shoots into the basin. It expands and slows down. The basin is 6 ft in diameter and sloped to drain downhill. When the water comes out of the basin, it is spread over a much wider area, but the volume is the same. I suspect once it's out of the basin and into my neighbor's yard, it will just regroup and reform a fast flowing stream until it hits the next neighbor's yard that has a french drain as well.

All I know is that I was out throwing the ball for my dog today and didn't have to give her a both when we were done. That has never happened the night after a big storm, so the french drain is working for me.

 

[ERD50]

The basin acts like a reverse nozzle. The water coming out of the 4" pipe shoots into the basin. It expands and slows down. The basin is 6 ft in diameter and sloped to drain downhill. When the water comes out of the basin, it is spread over a much wider area, but the volume is the same. I suspect once it's out of the basin and into my neighbor's yard, it will just regroup and reform a fast flowing stream until it hits the next neighbor's yard that has a french drain as well. ....

That's what I picture (the bold part).

.... All I know is that I was out throwing the ball for my dog today and didn't have to give her a both when we were done. That has never happened the night after a big storm, so the french drain is working for me.

But now that the basin is full, will it dry up before the next rain?

I suspect (if I followed your drawing), that the basin isn't doing much. And the french drain is what made the difference today.

-ERD50

 

[corn18]

That's what I picture (the bold part).




But now that the basin is full, will it dry up before the next rain?

I suspect (if I followed your drawing), that the basin isn't doing much. And the french drain is what made the difference today.

-ERD50

I think you are right.

 

[corn18]

Here's a pic of the french drain. Still have another 4 yards or so of 1" washed stone to put in to fill it up. Also a pic of the basin, which I decided to leave. It will be covered in decorative stone. The landscaper came today and he will be grading and sodding in two weeks.

 

[corn18]

Had a great soaking rain this morning. The pit worked well. It filled up but the overflow came out at a slow trickle vs. the river that normally flows into the neighbor's yard. You can see the extensive damage they have from previous rains (our yard ends at the pit).

 

[travelover]

Had a great soaking rain this morning. The pit worked well. It filled up but the overflow came out at a slow trickle vs. the river that normally flows into the neighbor's yard. You can see the extensive damage they have from previous rains (our yard ends at the pit).

You need to dig a bigger retention pond and buy some ducks.

 

[ERD50]

You need to dig a bigger retention pond and buy some ducks.

If you build it, they will come.

-ERD50

 

[NgineER]

You might want to try to dig deeper, not only will you have a greater reservoir, but you might also hit a layer of soil with much better draining capacity. Other than that your solution looks great!

 

[corn18]

You might want to try to dig deeper, not only will you have a greater reservoir, but you might also hit a layer of soil with much better draining capacity. Other than that your solution looks great!

Nope. It's filled and is what it is at this point. It will all be covered in grass in 2 weeks. We may just put 4" to 6" rocks over the basin.

 

[SnowballCamper]

I'd suggest planting some water tolerant plants along the drain (just beside, probably not right on top where there're is little soil), Here in the Pacific Northwest that would be something like Oregon Ash. Could be willows most anyplace else, but they can become a nuisance if you're not prepared for the deadfall and such. Lots of shrubs do well in wet sites. They would help take up the water, and get the water to infiltrate the soil more efficiently. Of course some people prefer the manicured lawn...it's just hard to manicure when the mower makes ruts... Good luck!

 

[AvocadoRV]

I had a very similar issue. Had to install a submersible pump to pump up 4 ft vertically and 25 feet laterally. Worked well. It got overwhelmed by severe thunderstorms, but the pump kept going until the surface water was gone. If you go this way, I recommend a good submersible pump with a float that is on a vertical rod. Avoid the float switches that are attached to a free floating cord, they seem to get stuck either up or down. The cord also gets stiff if the water is cold. If you get hard freezes in your area, you may have to remove the pump for the winter.

 

[skyking1]

Because I do this for a living I'm a little more adventurous. I would be interested in what the soil types are and how deep you have to go. As somebody mentioned above if you got into a free draining soil down below the clay layer, that water might just go away amazingly fast. Rather than dig deep and explore, you can try and find a soil log somewhere that'll give you an idea.

 

[corn18]

After a few storms, the french drain is still working great. And the neighbor's are putting one in as well, so that will eliminate the standing water in the basin. Life is good.

 

[Jerry1]

After a few storms, the french drain is still working great. And the neighbor's are putting one in as well, so that will eliminate the standing water in the basin. Life is good.

Yeah, it’s great to have neighbors who understand the benefit of certain public works projects and get on board with you. Good for you!

 

[Argus]

Consider this, given your description of 1.5" of rain and the size of your back hard shown on your drawing, that event generates close to 8000 gallons of water (excluding your roof drains...). To store that volume you would need a hole 10ft diameter x 16 ft deep. Not very practical. You will always need an overflow outlet from the sump pit. All the sump pit is doing is deferring runoff, not stopping it. The only water stopped is the remaining water after it fills and it stops raining. no water going in, that is.

All your french drain is doing is intercepting runoff water flowing onto your property and diverting it to protect your yard. Your downhill neighbor will need to install a similar system to what you have and so on down the hill to eventually getting to your lowest downhill neighbor. Pumping into the woods is a nice gesture on your part but i imagine your pump would be overwhelmed fairly quickly if you have another 1.5" rain event often.

 

[Mansderm]

My property was pie shaped and I had 3 neighbors abutting the rear property line. The problem is related to poor planning by the developer. I ended up hiring a company who brought out an engineer and they planned my drainage solution which required 7 drains being installed and tapping into the street drainage pipes. Expensive but definitely solved the problem for me and my 3 neighbors. But then an engineer who lived 6 houses down from that came over and asked what I did because now everyone in his area was having problems. So I explained and he was prepared to do something similar. When development is not taking this issue into consideration when building, anything you do can potentially cause a problem somewhere else.

 

[ERD50]

Consider this, given your description of 1.5" of rain and the size of your back hard shown on your drawing, that event generates close to 8000 gallons of water (excluding your roof drains...). To store that volume you would need a hole 10ft diameter x 16 ft deep. Not very practical. You will always need an overflow outlet from the sump pit. All the sump pit is doing is deferring runoff, not stopping it. The only water stopped is the remaining water after it fills and it stops raining. no water going in, that is.

All your french drain is doing is intercepting runoff water flowing onto your property and diverting it to protect your yard. Your downhill neighbor will need to install a similar system to what you have and so on down the hill to eventually getting to your lowest downhill neighbor. Pumping into the woods is a nice gesture on your part but i imagine your pump would be overwhelmed fairly quickly if you have another 1.5" rain event often.

Good points. And that 10ft diameter x 16 ft deep hole would need to be empty/hollow for that volume. OP filled the basin with 1" stone. I'm sure there's a number on the internet for that factor, but I'm sure it reduces the volume for water by.... a whole lot.

-ERD50

 

[Ronstar]

After a few storms, the french drain is still working great. And the neighbor's are putting one in as well, so that will eliminate the standing water in the basin. Life is good.

It would be best if you could get enough downstream neighbors together to tile it to an existing swale/ drainage course. Then you wouldn’t need the French drains. All the French drains are doing is collecting and storing water. You need an outlet for the water like others have said.

 

[corn18]

It would be best if you could get enough downstream neighbors together to tile it to an existing swale/ drainage course. Then you wouldn’t need the French drains. All the French drains are doing is collecting and storing water. You need an outlet for the water like others have said.

I talked to the direct downstream neighbor and they are putting in a French drains that will tie into mine. So don’t need the basin now. The last neighbor down stream already has a kick butt French drain that drains into the storm drain so I think we have a good solution for all now.

 

[indiajust]

I usually put in a dry well. One deep rocked in part with a clear pipe run to the bottom. Deep enough and it will absorb and dissipate water into the subsoil without runoff. Just drill a hole till you hit rock, spread the dirt around on top

 

[Ronstar]

I talked to the direct downstream neighbor and they are putting in a French drains that will tie into mine. So don’t need the basin now. The last neighbor down stream already has a kick butt French drain that drains into the storm drain so I think we have a good solution for all now.

Great! You may want to remove your basin - it may collect water and prevent it from getting downstream. Especially if the ground is such that the basin takes a long time for the water to percolate. The goal is to get the water off your property, not store it on your property.

 

[corn18]

UPDATE:

I talked to my neighbor's with their drainage guy yesterday. They are going to tie right into my system and continue it through their yard. That is perfect for me. I decided to remove the basin and just run the trench to the property line and left my pipe sticking out of the ground ready to tie into their pipe. Life is good.

 

[Ronstar]

^excellent!

 

[DD4L]

Had a great soaking rain this morning. The pit worked well. It filled up but the overflow came out at a slow trickle vs. the river that normally flows into the neighbor's yard. You can see the extensive damage they have from previous rains (our yard ends at the pit).

At the end of our trench we dug one last large 3-4 ft deep hole and buried a homer bucket drilled with 1 inch random holes all over it, then filled the bucket with 1 inch stone and outside it's perimeter and base to a thickness of about 6 inches.

We were able to grass over the top of it and it worked fine (ours was to get rid of a pond that was fed by three downspouts)

Good luck.

DD4L

 

[corn18]

UPDATE FROM OP:

Had a soaker last night. Nine hours of rain. Total of 2.5". I woke up at 0600 and it was still raining. The neighbor upstream had a stream running through his freshly planted grass. Washed all of his straw up against my fence. That fed nicely into my collector. We had no standing water. The neighbor down stream who just had a french drain put in had a river running where the french drain is. Washed all his straw away from his newly planted grass.

My yard is dry now. My french drain works a treat. The down stream neighbor did not put in a big enough drain. The contractor just used a trencher that made a 6" wide trench. It is just not big enough to handle the water. They should have used a backhoe and done a 12" wide 24" deep trench. That's what the french drain guy on youtube says. We did 12" x 18" deep and ours works great.

So, if you are planning a french drain, dig a big one or don't bother.