Basement Flooding

Please explain your question in greater detail.

If a "water relief hole" is "punched" in the bottom of a basement... where is the water to go?

Hi Wood I,

"water relief hole?"

You mean a drain?

Mike

Thank you Ozz. Let me paint a little different picture for ya. Lets say that a house does not usually have a water issue. The water table we will say is at 12 ft. The basement 6ft. Lets imagine I drill a water relief hole about 4 ft beside the outside of the house. I drill it 50ft deep. The pipe is solid pipe from 8ft to 50 ft. At the 8ft level there is a check valve and the pipe is perferated to the top. Even if I have to go to 100 ft. I could do that. just need more pipe, ha.

Woody

Let's see. Water table: 12 feet below grade. Hole 100 feet deep or one mile deep would still have only the capacity from 12 feet to the surface.

I'd call this a well. I think you will need a pump to keep it empty.

If the water table is only down 12 ft that's all the farther you would have to go any farther is a waste. The problem will be how much water can now be forced into the ground. Unless you use a large diameter pipe will have issues with it filling up. If its ground water outside the home. On the lowest side of the house dig a ditch away from the house out to a drain field. Fill it with crush and run to about 3 ft of surface replace top soil. Please observe local codes for your area.

He's looking for work for his drill rig. He wants to go down, not out.

Do you own a lot of extra pipe that you're trying to hide somewhere? It fills up with water to at least the water table, possibly more depending on the time scales.

What exactly are you trying to achieve?

So... your not trying to "vent" out the water from basement? You are proposing drilling a well like structure 4 feet from the outside of the house, 50 feet in depth with a check valve (I'm assuming that it allows water down.. but not back up in the case of water level rise?)

What purpose will this well-like structure serve, and how does it relate to the basement?

Yes, RVZ717. The issue that I, we are facing is called "Urban Sprall". Me father lives in a condo complex and there is not enough green space. The basements, (here in Canada) have weeping tile to take the water away from the basements. "Stop the basement from flooding"! The issue is most of the water is run thru the eve's trough out onto the narrow road where it freezes in the winter and the older people have fallen and hurt themselves. I am trying to find out if I plumb this rain water into the ground, would it be a good thing. I do not want to make a place for someone to dump oil if you know what I mean. I would like to do a good thing here and am looking at contamination issues. permitt issues. What if I drill into an "Artizan well"? Would and could I make something like this work or was it a bad idea? Could I place a filter system, (Charcoal filter) in the top section? Could I make it so that it would be tested once a year. All these extras add up and would it be fesable?

Dear Wood,

If there are Condos then there must be storm sewers nearby. Can you connect to the storm sewer using a check valve?

This makes more sense to me. I have to agree with the former suggestion, get a sump pump and pump the water to a location where it will not flow back towards the house. Otherewise, you are just paying to circulate water. Also, install a check valve so water cannot backfeed into the basement.

On to your hole in the ground idea....

If the ground water is perched on an impermeable layer,such as clay or bedrock, and below that is a permeable substrate, then the hole may not fill with water as others have suggested. But the cost is going to be prohibitive. A sump pump and some piping will likley cost less than $1,000. Drilling a hole in the ground will easily three times that or more.

I can't help but think there are far simpler, and cheaper ways to keep the basement from flooding.

Seal it off...

Pipe and pump the water to a proper drain field...

Pipe and pump it to the municipal wastewater...

Move...

Also, I would think (but really have no clue) that you would need some kind of permit to drill what you are thinking, and I'm sure the cost would be the highest of any of your possible solutions.

Is the urban sprawl not requiring a sump? Yes you should run this water thru your pipe to the sump instead of onto the street.

Dear Wood, Tell you what. Just put the house on stilts and turn the basement into a swimming pool.

Hello Wood I,

Not sure what you mean by 'water relief hole'?

You cannot just make a hole and expect any water to drain away, unless, you live on a hill!

Let me explain...........................

Making a hole in a basement or floor which may already be below the local ground water 'Table' level will allow the 'outside' water into your basement rather than letting water out.

If you have a raised house or live on a hill, you could possibly allow water to bleed away via a properly installed drain pipe and 'U' bend.

If the basement or your house is on level ground, the water table will not be far below, chances are any water you get rid of will find a way back into your house.

As long as the basement or house is 'water tight' you can pump any water out and it should not get back in, as long as any water or ground outside your home dose not cover any 'vents' on the ground floor or basement.

Please keep in touch and we will help you.

bb

Hello bb,

I was guiding towards the idea of an urban run-off mitigation system.

Hi wire,

Thanks for the reply post.

There is a lot of help on that page which sounds like it can help in this situation?

As others have mentioned, I think the OP is making hard work of this problem. Another post mentions digging a trench and filling with hard core or similar.

My friend did had ground water running on and under the surface of his garden and it hit his house and made it moldy. He dug a trench, filled it with pea shingle all round the base of his house, and the water followed that route and after a year the mold stopped growing. So I know that works! It depends entirely on the amount of water you have to deal with though?

bb

It seems to me that you are considering what amounts to a groundwater recharge system. I once participated in the design and construction of such a system for a shopping center located along a former Lake Erie beach ridge. Survey data revealed that there was no visible means of surface drainage and no existing storm sewer system that would provide sufficient capacity for the 20-acre site that was being converted from a 100% grass surface to a 95% hard surface, even with the use of a large stormwater detention system.

Since the soil profile was a clean beach sand to several tens of feet deep, after obtaining soil samples and performing the appropriate laboratory testing, we proposed doing a percolation test to time the absorption of a large volume (3,000 gallons) of water into the soil. Since the results were very favorable, in fact better than predicted by a factor of 2, and laboratory testing for permissivity values for soil samples obtained from various locations and depths on the site were in accord with the field testing, a system of perforated storm drains was designed for the site. The design was based upon some sophisticated computer modelling, along with empirical data and common sense, and it resulted in the installation of a system of large diameter (48") perforated pipe that would have the volumetric capacity to contain the runoff from a 100-year storm event until the runoff could percolate into the soil. In addition, the parking area was designed in such a way that it could accommodate some ponding without it being a hazard, until the water could dissipate. To my knowledge, after 14 years of use, the system is functioning as it was intended.

In your situation, you would need similar conditions to permit what you are contemplating. Also, you would likely need approval from the authority that is responsible for groundwater quality. In our case, the entire area was served by a municipal water system and the groundwater regime was such that there was no possibility of contamination of any potable water supplies. If you are considering a well as a means of getting your excess runoff back into the aquifer, you would need a significant amount of data on the soil profile, terrain, etc., to even start to consider a design. Unless you have an aquifer with a huge capacity for recharge, you are wasting your time. Furthermore, any system like this for your situation would be very costly, if even possible.

Well, Mr. Doogleass. I am very interseted in what you have just told me. Is there a name or location to this shopping mall? The "Ponding idea" is great but for the condo, here in Alberta , it will freeze. The large diameter pipe, 48" . That is huge! I was thinking along the lines 1 4 inch pipe for approx 500 square ft of surface area. Now, The total number of holes is only about 8 maybe 10 in this situation.

This was exactly the information that I need to take to the city engineers,

Again , thank you.

Woody

If I am not mistaken, Wood I intends to fully line his well with pipe. How will the water percolate into the soil in the right zone?

Sounds like you know your stuff.

He would have to use a slotted casing, either by means of a pre-made screen (expensive) or by using a PVC casing that is easily slotted with a circular saw. The slots should be consistent in size with the grain size of the permeable zone. If the grain sizes are fairly small, i.e. coarse to fine sand, the pre-made screen is a better choice, as they are available in a variety of opening sizes for that purpose, i.e. to prevent the migration of the sand/gravel into the well.

Another alternative, and one that makes a lot of sense, is to drill a larger hole than the casing, say 12" diameter, and then pack the casing and attached screen in pea gravel. This would add to the storage volume of the well, as well as provide a better interface for disbursement of the runoff into the permeable zone.

In effect, this is the same method that would be followed for building a water supply well or, more accurately, a groundwater dewatering well. In the latter case, the goal is to intercept any groundwater in the soil profile down to and including the aquifer.

Doogleass. You have been around the rig's before I take it. Yes I am thinking along the lines of a water funnel effect. The smaller diameter hole I can go deep with. Putting in a larger casing on the top.

You da man Doogleass!

Thanks

Woody

PS. Thanks to everyone else who has taken an interest in this.

Woody

Gotta give ya a GA. Thanks for sharing your knowledge.

Okay, I think "water relief hole" is what folks in rural upstate NY call a "dry well".

So long as the water table is deep enough, these work just fine to dispose of stormwater. They even work in winter, if you dig down below frost.

Dry wells only work if the soil is porous enough. If it's not, then at peak flows the water will back up. A check valve can help prevent this, but then you still have the problem of water with no place to go.

Possible problems:

1. Contamination of groundwater- do you get your water from a private well? If not, then it's probably not an issue, especially if there are septic systems in use in the area also.

2. Changes in groundwater- the water has to go somewhere. One gentleman I heard of plumbed all of his gutters to a well-built dry well. However, his house was on a slope. The water flowed through a porous layer of fill but on top of the clay subsoil, and resurfaced in the garden. The next time his wife went to work in the garden, she ended up knee-deep in muddy quicksand!

3. Saturation of subgrade- the purpose of the whole exercise is to get water away from your foundation. A dry well that channels all the rainwater under the foundation can turn the soil under the footers to mud- NOT a good thing. Again, the water has to go somewhere.

Kind of hard to recommend a solution without seeing the "lay of the land" as it were, and knowing the soil composition, where other buildings and property lines are, etc.

why is there no french drain around this condo. sounds like the zoning board along with your city engineers need to take a look at the zoning ordinances. They should have a whole page about impervious coverage

Good evening MR Moore. Yes, there are some issues with the elevations and sloping of roadways through the condo complex. Strom drains are 2 and 3 inch above grade and 4 and 5 ft to the high side of centre. Aidrie - Alberta is mostly on large fractures of sandstone with, gravel, sand /silt and clay. There is a creek running through town, "Nose Creek". It is a dry year out here and the creek is quite high. The developers of new areas are required to have a clay base, plastic lined, holding pond for surface run off. I guess the answer would be to widen the creek to allow for more volume due to development. As an Albertan I worry about enviromental impact. What chemicals are already running into the creek? What is the safest, best way to pass the water along down stream with as little foot print as possible? What are our options?

Holding ponds-(Evaporation)?

Dry wells-(Rock filteration)?

Surface run-off (creek banks and water moss)?

All 3 ?

Hey, I'm not an engineer- I'm just a dust sucking driller.

Woody

Here's my belief

You can pick your friends and you can pick your nose but don't pick your friends nose.

Dear Mark, I enjoyed your post.

I am not familiar with the Dry Well term. I am familiar with gravel and french drains and different dirt. In ten years of digging ditches for footers and foundations in places no machine can go, I am very pissed I never found any gold.

Clay will cause you to have to work hard to get water to go where it won't tear the building down, or otherwise make it unlivable.

In the area I live, Artificial Re-charge was used to manage the stormwater of several new developments. Now, my basement is flooding several times per year, because the recharging has caused the water table to rise.

Had the appropriate testing been done, this could have been avoided.