Learn Me Some Drywells & Automatic Sump Pumps

[OCJohn]

My name is John and I have a drainage problem. My neighbors here in sunny southern California are not exactly flush with irrigation and drainage experience, so I'm hoping to find some wet-region wisdom here.

In a nutshell, I need to move stormwater from our backyard out to the street (and city storm drain) about 80 feet away. Seems like the least invasive route would be some sort of basin/float pump combo buried in the backyard with a PVC line running out to the curb.

Last year I installed a channel drain across the driveway, in front of our detached garage. Behind the garage, I've got a full width french drain that is also new. Both drains are 4" and terminate (for now) into the backyard about 30 feet apart. In light rain, everything flows to the yard as intended. Once backyard becomes saturated, however, the channel drain backs up and pools against the 18' garage door. Then floods the garage.

My temporary fix has been a $60 submersible pump, below grade at the channel drain's exit. It's barely adequate and also completely manual. Helpful only if I am both home and awake. It's time to sack-up and make things right.

Seeking input, recommendations and words of wisdom on...

• drywell/basin sizing
• pump type, manufactures and sizing (with reliability, serviceability and value in mind)
• pros & cons of using a single basin/pump for both drains*
• hard lessons you've learned that I might avoid

You folks are my people and know how to do things right. And I'm guessing most here have more wet climate drainage experience than I do, so thanks in advance for any help you can offer.


Everyone loves pictures, so here's the sort of stuff I'm finding on Amazon (but know nothing about)...

 

[RJSakowski]

I live in a wet region with a small stream about 50 yds, from the house, Fortunately, the slope drops away from the house to the extent that it is below the basement floor at 30 ft from the house. The day I moved in, there was a heavy 4rain and the next morning all my portable power tool which I left on the basement floor under six inches of water. I installed a sump pump shorty thereafter. Unfortunately, they require power to operate and heavy rains are often accompanied by power outages. To solve that problem, I tunneled under the footing and ran a drain line out to a lower elevation, thus creating an automatic drainage system independent of available power. I used 3" PVC pipe. It has a built-in trap by virtue of tunneling under the footing which keeps stray critters from entering.

 

[OCJohn]

Man, I didn't think about power outages. Dang.

No easy gravity solution on my lot, though. Unfortunately. I like simple and passive.

 

[woodchucker]

I live in a wet region with a small stream about 50 yds, from the house, Fortunately, the slope drops away from the house to the extent that it is below the basement floor at 30 ft from the house. The day I moved in, there was a heavy 4rain and the next morning all my portable power tool which I left on the basement floor under six inches of water. I installed a sump pump shorty thereafter. Unfortunately, they require power to operate and heavy rains are often accompanied by power outages. To solve that problem, I tunneled under the footing and ran a drain line out to a lower elevation, thus creating an automatic drainage system independent of available power. I used 3" PVC pipe. It has a built-in trap by virtue of tunneling under the footing which keeps stray critters from entering.

1st if you have water from a water company you can install a sump pump that backs up your primary by using the water as a pump driver.
2nd, it seems unfortunate that you moved the water from your driveway to your yard, and now you want to clear your yard.
if you can, it would seem much easier to divert the water to the final destination rather than the yard.
3rd, if that's not doable the best way to handle that is to have multiple drains connecting to the basin you show in your pic, and have that drain to the street (or final destination). I have a system with 2 sumps but I don't run power. They are collection and drain systems to move the water from the ponding area to the area that doesn't pond. the second is an overflow for the first and then that overflows toward the road. I am not allowed to drain to the road, so I get close to it, and let it go on it's own.

 

[verbotenwhisky]

Man, I didn't think about power outages. Dang.

No easy gravity solution on my lot, though. Unfortunately. I like simple and passive.

I have a house on a small lot and the back yard is graded to slope from the middle to the sides, front to back down the side of the house to the street and the drains...

 

[alloy]

Interesting this subject came up as I'm in the process now of adding a battery backup sump pump to my shop.

I have a 110v zoeller pump as my main pump. At first I had one from harbor freight and lost 2 of them in short order. I gave up and got a zoeller and that was over 3 years ago. The pump is in a ditch behind my shop and I have two 24ft. harbor freight sump pump hoses put together to discharge the water far enough away from my shop that it won't drain back into my shop. The hoses are $8 less each than home depot is and are exactly the same thing.

Harbor Freight Tools – Quality Tools at Discount Prices Since 1977

Harbor Freight buys their top quality tools from the same factories that supply our competitors. We cut out the middleman and pass the savings to you!

www.harborfreight.com

And RJSakowski as said, there are power outages. and they seem to happen when it's raining heavily and my shop ends up with 2 inches of water in it. The outages usually don't last very long, but they always happen when it's storming. So I bought this pump and battery, both from amazon. They were both less than buying locally and no 60 mile round trip to get them.

https://www.amazon.com/gp/product/B005MKGRJQ/ref=ox_sc_act_image_1?smid=ATVPDKIKX0DER&psc=1

https://www.amazon.com/gp/product/B0CQ7NKFVC/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

I have my main pump dug into the ditch inside on old milk crate. I think I have enough room to put my second pump in with it.
I looked at the fancy sump pump basins and decided they weren't worth it when a free milk crate would do the same job, and has been for 3 years now.

 

[OCJohn]

1st if you have water from a water company you can install a sump pump that backs up your primary by using the water as a pump driver.

1 – I’m not understanding this. We get water from the city (no well), but what is a pump driver?
2 – It is unfortunate. The front half of the DW slopes frontwise to the street. The back half slopes back to the garage. Also slopes out to the property line between us and the neighbors. When we moved in 22 years ago, there was a subtle depression there which carried water to the street. But when the neighbors built an addition, they built a block wall there for privacy in their new bedroom. That took care of the depression and now my garage is the low spot. [The neighbors are GOOD people and put up with a lot living next to me. So let’s please not get off the topic of a drainage problem that I WANT to solve…]
3 would be my dream, but I just don’t have the topography to pull it off.

 

[OCJohn]

@alloy thanks for the links. I like your thinking. I’m only looking at deep, rigid basins because my ideal placement is under the lawn with a turf level pop-up for overflow. I’ll sleep better at night not having to worry about the gardener collapsing my drywell and breaking his leg. And I’ll get more drain capacity if I don’t have to fill it with rocks.

 

[woodchucker]

1 – I’m not understanding this. We get water from the city (no well), but what is a pump driver?

The city water drives the impeller for the pump, rather than electricity. It works when you have city water. I don't so I can't utilize it.

 

[OCJohn]

See, I knew I’d learn something with this thread!