Rebuilding an old pond

[jacquirenee]

Hello!

We bought our house in May of 2009, but also got married in August of 2009 so we did absolutely nothing with our landscaping or garden last summer. Now I'm ready to roll and my biggest project by far is to rebuild a former garden pond on our property.

The old owners obviously put a lot of time into this pond. It's pretty large (it's a strange shape, but it's approximately 15x20, I'd say), it has a concrete spillway at one end and some broken down features (like a little wooden bridge at the other end). Unfortunately the owners between those people and us had the house for about 8 months and were clearly in the process of dismantling the pond. All the edging rocks have been removed and put in a big pile, the pump and underwater lighting are just in a heap at the bottom of the empty pond, electric cables, tubing, and all, under leaves and debris. There is a very sturdy liner (I would guess it's 45 mil epdm, but I can't be sure), but the pond does not hold water when it rains.

So I need help from you all! I have been researching like crazy in preparation for my spring break this week (I'm a teacher and finally have the time to invest in my pond now!), but most of the things I've seen are about building from scratch. I'm lucky that I have a very nice bi-level hole dug, with a lot of work already done, but on the other hand, I'm not sure where to begin. Can I ask you a few questions?!

1) Should I test the old liner for leaks? Is it possible that it doesn't have a leak, but just doesn't hold rainwater? I've read that a good way is to stick a garden hose under the liner and see if any water seeps up through it anywhere. Would you recommend this? I've read that patches work very well, and also that most EPDM's won't spring leaks. I would estimate the old liner must be at least 10 years old, but I have no idea... Should I just forget it and buy a new liner?

2) If I buy a new liner, should I just install it on top of the old liner? This seems like a good idea to me, since it provides another layer of protection, etc. But then again, I know nothing!

3) We don't want fish, but do want aquatic plants and hope to attract frogs. Do I need the high GPM (and expensive!) pumps and filters that are recommended for this size pond if I don't want fish? I was thinking of just using a pump with fountain attachment for aeration...would this be enough?

I'm so glad I found this forum and hope I can learn from your expertise! Maybe someday I'll be able to help out other newbies! :lol:

 

[DrDave]

Welcome to the forum!
Fill it and watch the level till it stops leaking. Your culprit will be at the water level. If it is running, the problem could be flow not returning to the pond. This is common and seems to effect all of us at one time or another. I just spent 4 hours fixing mine again.

 

[koikeepr]

If the liner doesn't hold water when it rains, the leaks could very well be on the pond floor. If it was me, and knowing the liner is 10+ years old, I would replace it. There's a vendor on ebay that sells 45 mil pond liner for just 38 cents a foot.

And yes, you could just lay the new liner on top of the old one without much trouble and it would provide you some extra protection as you mention.

If you plan on no fish (or maybe just a few goldfish), you really don't need a terribly high GPH pump. Laguna makes a pump such as you describe with the fountain on top. It is very good and uses litte electricity. I actually have one in my attic. I think I used it 2 years when I had a much smaller pond. I believe I still have the box and such. I think it's the Powerjet 1500 that is good for ponds up to 3000 gals. It looks like this: http://www.lagunaponds.com/lagunaeng/powerjetpumps/pjet1500.php?link=1401. If you don't mind a used one, you can certainly PM me for it and I can send it your way.

The other thing you willl need to think about is a filter, too.

 

[jacquirenee]

Thanks for these tips! Very helpful. Actually, today my husband and I got out and did some work to prepare and when we cleaned the debris out of the pond, we discovered that those in-between owners had actually slashed the liner in three places as their way of draining the pond. So new liner it is! It was a Firestone EPDM, too, I discovered, so I'm really disappointed that they did that.

I will definitely be checking out pumps and filters, so thanks very much for the advice! I am sure I'll be back here soon to pick your brains some more!

 

[owlbassboy]

oh gutted on that one, why on earth would you slash a good liner

 

[DrCase]

Welcome to the forum..
The new liner will let you know what you got ...
and you wont have any new leaks for a while
i would also lay it on the old liner

 

[DrDave]

Dittos.

 

[Daytongirl]

good luck to you! Puting the new liner over the old is a great idea. But....Why in heavens name would you let a pond that size go with just plants and maybe frogs??? Once you catch the fish bug, there is no cure. I would say just try goldfish (cheap) and then see where your heart and imagination take you....all ponders know where this road leads ; )

 

[koikeepr]

If fish are added, then you have to make sure to get a pump/filter that can handle a turnover rate of your entire water volume at least once every 1.5 hours.

I don't disagree with Daytongirl...a few little fishies will make you smile.

 

[jacquirenee]

Thanks again everyone! I really love fish and always wanted a fish pond, but I'm trying not to bite off more than I can chew! You're probably right, though...I'll get sucked right in once I do it. That's what my husband is afraid of. haha.

I will keep you posted on our progress and hopefully also post pictures as I go along. Thanks again!

p.s. koikeepr, I tried PM'ing you, but they wouldn't let me since I don't have 10 posts on the forum yet. Can you PM me? I think I'm interested in the pump and wanted to ask advice on filters. Thanks!

 

[jacquirenee]

Hello again! Curious about pond liner sizes...I've been entering my calculations in a lot of calculators online and getting really different results. My pond is roughly an L shape...the longest it is (long side of the L) is around 19 feet...the widest (short side of L) is 16. It has one deep pool at one end of the "L", about 2.5-3 feet deep and maybe 4 feet in diameter, one medium depth pool at the other end, about 1.5-2 feet and about 3 feet in diameter, and the rest in the middle junction is only about 6 inches deep. Most of the calculators I'm doing ask for a max depth, but the max depth is only a small portion of the pond. I was hoping to do a 20x25 liner. Most calculators are telling me 22x26, but these only ask for max depth, not average depth, plus they are for an oval or rectangle shape, whereas I'll only be using about 2/3 of the total liner actually...it seems like a huge waste! Do you think a 20x25 will be adequate?

Thanks again for all your help!

 

[koikeepr]

pretend your L is just a looooong rectangle and ignore the bend--so 19+16=35 feet, but you need to account for the turn to make the L. You don't mention your width.

You will have a lot of waste because of the L shape. You need to make your liner wide enough to make the L-turn and still reach across without cutting the liner.

Since your pond is an odd shape, I would call the liner shop you want to buy from before placing an order so they can help you account for the odd angle to make sure you have enough. It's better to have too much than be too short when it comes to pond liner. But, yeah, you'll have a bunch of waste. You just gotta go with it.

 

[DrDave]

Average depth means nothing when calculating the liner size. You must go with the maximum size in every direction and I always add an extra 2' to be safe. I would rather have more waste than find out it is too small.

 

[jacquirenee]

Okay, this is getting over the budget my husband has set for me...I'm wondering if it might be better to patch the slashed areas? I know that's not the ideal situation, but they trust it with EPDM roofing, so why shouldn't I?! :bouncycig:

It looks like my choice is either patch or fill in. It might be sacrilegious for me to ask all of you pond lovers and experts, but any tips on patching? Each slashed area is about a foot long....one area they cut out a circle about 6 inches in diameter. I figured I could go to my pond store and get like a 6x6 sheet of PondGard, and all the QuickPrime, splicing tape, and lap sealant to fix all three slashed areas. Any thoughts?

 

[undrtkr_00]

That would probably work, and will probably be cheaper than replacing the whole darn thing. But, I'd test the patches for a while before moving on with further stages of the project. Patching can be tricky, and you want to be sure you have it sealed up tight.

If you aren't going to have fish, or even just a few goldfish, you won't need any kind of filter to keep plants alive. Just a pump to keep the water circulating should be enough.