sump pump well?

[NM_Shooter]

I've decided to concrete the floor of my RV garage.

Once or twice a year, during monsoon season, I get some water that leaks in the door of the garage.  Since this has been a dirt floor in the past, I have not been too concerned.  On one occasion, there was a lot of water. 

So... I want to make sure that the floor drains to a low spot, and that I have a sump pump ready to remove the water.  This may be problematic in more than one way... the water may have sediment in it.  I am also building a swale to divert water around the garage, and putting in a small curb at the entry to the garage, but I worry water will still get in.

Questions :

It seems as though I should dig the well first, line it with concrete block, then have the slab poured, then waterproof the inside of the sump pump well.  Any guidance on this?

Since the well will be more or less in the center of the garage, with the Trailer parked over it, should I have the discharge pipe poured into the concrete? 

I don't want any water to remain in the well.  Should I not waterproof the sides and bottom to allow residual amounts to seep out?

Thanks!

Frank

[Don_P]

I haven't used this particular company but sump basins along these lines are pretty common;
https://www.acwholesalers.com/Little-Giant-Water-Pumps/14940655-CS-SS-Pre-Packaged-Crawl-Space-Sump-System/32941.ac?gclid=CP2ghtj697wCFS9p7AodmjkAXg

[NM_Shooter]

Thank you.

I'll take a hard look at that.

I spoke to a concrete contractor today for a quote, and he suggested fixing the grading so that it does not flood into my garage.  A good idea, but I fear that even with grading I will still get some water intrusion.  Maybe I will try both of these things in the hopes that I won't get water in, and if I do it is able to be removed. 

[Kramer]

Generally, the floor would be sloped say 1/8" in 10' towards the door(s), so any water that entered would simply run back out.

I'd do that, and fix whatever grading issue you have in front of the door before I would ever consider a mechanical solution to the problem.  Also, a french drain, or a poured concrete trench with a grate over it, in front of the door may be a solution if there is just too much water.

[Redoverfarm]

Frank I would try to find a surplus plastic barrel .  They are pretty common around here and would just be a fraction of the cost in comparison to maufactured ones.  You will have to plumb the discharge pipe under the floor to the nearest wall in which you have a low lying area as well as the electrical feed to operate the pump.

Is there no way to slope the floor to the center and then pipe out under the floor and eliminate the need for mechancial means.  I put in a 2 car garage and put seperate floor drains for each bay.  Keeps theings nicer when you pull in that the snow,ice  & rain goes under the vehicle and you are not constantly steping in it getting in and out of the car/truck.  If you go this route remember traps in a gravity flow system.  If you are concerned about sediment it can easily be flushed with a hose to the outside.

[flyingvan]

  I have one under each house---I don't know how standard this is, but I just dig a 16" diameter hole as deep as I can, about 5'.    Then I take a 8" diameter PVC pipe and drill 1/4" holes about 14" from one end.  That end goes in the hole then I drop some water stop concrete in, maybe 3" worth.  Then the hole is filled in around the pipe with pea gravel, and a sump pump with a float switch goes in.  You have to make a fairly tight fitting lid or mice will fall in and rot---cleaning that out isn't very pleasant.  On rainy days I can hear the pump cycling every now and then.  I think I installed the one in the main residence 18 years ago and the crawl space stays bone dry...Make sure there's a check valve at the ejection port or else the pump just keeps drying the sump, then the water siphons back in again.

[Danfish]

My experience with sump pumps is that they are just another maintenance headache, to be avoided if possible.  Slope pad toward door and install trench drain at door to catch water coming from either inside or outside.  Route drain to a dry well outside structure.  Did this with a garage where drive way slopes toward door.  After several years of rain and snow nothing gets inside the garage.

[MountainDon]

FWIW, I don't think Frank has any slope on his property. Most of where he is is very flat; flat enough to ditch irrigate.

[flyingvan]

  Passive drainage is the preferred method whenever possible....  Not always possible though

[hpinson]

I have a similar problem -- our driveway slopes downwards towards the garage and my front door, and flooding can become a minor, and very occasionally major, problem anytime there is a sustained heavy rain.

I was considering trenching about 2 feet right in front of the lip of the garage concrete pad, and running that trench out to lower ground.  In the trench at the garage itself would be a perforated pipe with screen around the perforations, connected to pipe out to low ground.  The trench at the garage would then be filled with pea gravel, and just fill below.

Would that work?

[kenhill]

In the drainage section of the Big Box Stores, they have a pvc trough with a grate on the top that you could put infront of your concrete pad made for this purpose.  You can remove the top and clean out if needed.

[flyingvan]

If you go with the perforated pipe, invest in that sock that you can slide over it.  It should greatly extend the life of the drain, keeping it from silting  up

[Kramer]

If you go with the perforated pipe, invest in that sock that you can slide over it.  It should greatly extend the life of the drain, keeping it from silting  up

Alternatively, you can wrap it with decent ground cloth.  I do that, and zip tie it in place prior to backfilling.  YMMV, but decent ground cloth is cheap and available, the drain socks not always so much.