Pond relining in Boise, Idaho

Pond relining in Boise is often the answer when an old pond came with the house, it's cracked and leaking, and you'd rather not rip it all out. Maybe it's a concrete basin or a hard plastic shell, and you're topping it off every few days. I fit a new flexible liner inside the old pond so it holds water again, and you keep the spot, the shape and most of the stone.

Relining is not the same as replacing a liner

People mix these up, so here's the difference:

• Pond liner replacement is for ponds that already have a rubber liner. The old liner comes out and a new one goes in its place. I cover that on my pond liner replacement page.
• Pond relining is for ponds with a hard shell, like poured concrete, mortared stone or a preformed plastic pond. The shell stays put and becomes the base for a new liner laid inside it.

Relining can also work when a rubber liner is worn but the hole under it is in good shape, and you'd rather lay a new liner over the old one than dig it all out.

Ponds that make good candidates

Relining works well when:

• The concrete has cracks, but the basin is still mostly in one piece
• A preformed pond has split, warped or gone brittle in the sun
• The pond leaks somewhere you can't find, and patching has failed more than once
• You like the size and the spot and just need it to hold water

It's a poor fit when the shell is sinking, tree roots have pushed through, or the pond is too shallow for what you want now. Then a rebuild usually makes more sense.

Why old ponds crack in the Treasure Valley

Concrete ponds and our weather don't get along. Water soaks into tiny cracks, freezes, expands and pushes the crack wider. That happens again and again each winter here. Clay soil also swells when wet and shrinks when dry, which shifts the shell. Hard plastic ponds get baked by hot summer sun until they turn brittle.

There's a water quality problem too. Concrete leaches lime into the water, which pushes the pH up. Our water already runs alkaline, so an old concrete pond can climb high enough to stress fish and feed algae. A rubber liner puts a barrier between the water and the concrete.

How relining works

• Drain and move fish. I pump the pond down and move fish to aerated holding tanks filled with their own pond water.
• Clean out. Sludge, old plants and loose stone come out.
• Prep the shell. I grind down sharp edges and fill deep gaps so nothing pokes the new liner. With a preformed pond, I either cut the plastic out or leave it in place as a base.
• Underlayment. A thick padding layer goes down first to protect the liner from the concrete.
• New liner. A fish-safe EPDM rubber liner goes in, folded neatly into the corners and run up past the old edge.
• Hide the edge. I set stone over the liner edge so you don't see rubber at the waterline.
• Refill. I fill with dechlorinated water, start the pump and bring the fish back slowly.

Upgrades while the pond is empty

An empty pond is the cheapest time to fix other things. Many old concrete ponds never had real filtration, so I often add a skimmer and a biological filter. Some owners deepen the bottom for fish, add a waterfall or put in lights. If the pond has other issues, my pond repair page covers what else I fix.

What changes the price of relining

• The size and depth of the pond
• How much cleanup and shell prep it needs
• How much stone has to come off and go back
• Whether there are fish to hold, and how many
• Upgrades like a skimmer, filter, waterfall or lighting

Relining usually costs less than breaking out a concrete pond and starting over, because the shell stays and there's less digging and hauling.

Not sure if it's the shell or a leak?

Sometimes a pond loses water from the waterfall, the plumbing or a low spot in the edge, not the basin. I check that first. If the shell is sound, pond leak repair may be all you need. If you keep koi, my koi ponds page explains the depth and filtration they need, which is worth planning for while the pond is empty. All my pond work is on the pond contractor page.

Relining ponds across the valley

I reline ponds in Boise, Meridian, Eagle, Garden City, Nampa, Caldwell, Kuna, Star, Middleton, Hidden Springs, Sun Valley and Ketchum.

If your old pond won't hold water, schedule a consultation about pond relining in Boise. I'll look at the shell and tell you straight whether relining, a repair or a rebuild makes the most sense.