How should I remove a swimming pool from my back yard?

Question

Our house had a nice cedar pergola in the backyard, about 20'x16', whose posts began to rot at the base. It was covered in grape vine... Nice for shade but not for a falling down pergola. Needless to say, a few months ago we got a pretty good wind storm that finally blew the thing over.

I finally got to dismantling the thing and would you believe it, there's a damn swimming pool underneath it! At least that's our best guess as to what it is.

It's only ~3.5' deep at the deep end and ~2.5' deep at the shallow end... So if it was a swimming pool it wasn't for very large people.

Anyway, we have found ourselves with a huge amount of buried and likely reinforced concrete smack dab in the middle of our back yard. The original plan was to 1) remove pergola 2) plant grass. That's now a lot more complicated.

So the main question is:

How do we remove or mitigate the concrete situation so we ensure the backyard can be enjoyed for a long time.

Answer 1

Where I live (NJ, USA) it's illegal to bury a pool. If the pool was filled with soil and hidden it's possible you would have recourse to get the person who did it to pay for remediation. Unlikely but possible. However if the pergola structure was built over the pool like a platform, it may be legit.

The correct way to permanently remove a concrete pool, where I live, is to break the concrete up into pieces no bigger than 8 inches in any direction. For something that size you're looking at a jackhammer attachment to a sit-in machine of some kind. I think I saw a specialized one with an arm that had both a jackhammer and back-hoe on it so the pieces could be moved to their desired resting place..

You start by breaking up the floor of the deep end, then do the shallow end and push the pieces on top of the deep end. Then you break up the walls and make a layer on top, then the deck goes in last. All in small pieces.

All biodegradable material MUST be removed and not buried in the hole, as must metal, plastic, and anything other than concrete and dirt. Leaving beams or logs in the hole will cause problems later (and fail inspection).

After doing all that you get an inspection, then add clean fill if necessary (free from a local construction site) and finish with landscapers cloth and top soil. Expect some subsidence and to re-apply top soil after a couple of years. You may not need much fill but in a more typical pool with a real deep end you would. I'm not sure if the cloth goes between rock and fill or between fill and top soil. If someone adds that to the comments I'll correct this.

If your house is rated (for local taxes) as having a pool, removing it will reduce your tax bill and makes it worth the hassle of pulling permits and doing it properly.

Note there may be live buried wires in the area beneath and around the pool. Get to know the installation before you proceed, especially any surrounding lighting or pool machinery.

Answer 2

Sounds like a nice size Koi pod; I am jealous , mine is only 5 X 10. Depending on intended use , filling it is a option. Use any cheap fill then put about 6 in. of topsoil on top. At Koi / pond club meetings, I have heard about more ponds being filled than being removed ( if reinforced concrete).

Answer 3

To propose one solution to my question: rent a ride-on-back skidsteer with a jackhammer attachment, break it all up (bottom included for drainage) then backfill with dirt. Not sure if there would be long term consequences other than feeling sorry for the poor person who tries to dig in this spot in the future.

Answer 4

You have suggested jackhammering, but from my experience concrete cutting is the better option for thick and/or reinforced concrete. It is cleaner, quicker, less noisy, and less frustrating. Call an expert to do it.

I would remove the concrete rather than leaving it. Concrete immediately underneath the soil makes it more difficult to grow anything. It is a large amount of concrete (I would estimate about 8-10 tonnes) so will definitely cost a bit to dispose of, but it will be worth it in the long run.

Answer 5

First question is, what state and county do you live in? I can assure you that your state Environmental Protection Division and your local county or city has a code or an ordinance that's gonna cover this exact thing. Take a few minutes to either go online, call or even better take a field trip to your local governmental building and go to the code enforcement department and I'm almost positive they will either one, give you the exact answer you're looking for or two, they'll be able to lead you to exactly where you need to go to get the answers you're looking for.

I hate to see people being led to spend money based on opinions of others who don't first ask the correct questions about your situation for example, what state do you live in? Every state has different laws about everything, always remember that sir. Next, a septic tank will never, ever look like a swimming pool with a walk in entrance, that's just absurd on all levels come on now, let's be real here and never will a Coy Pond or not one which I've ever seen in my 52+ years anyway.