This article is directed to those people who are considering building a liner pond and to those who already have one.
For twenty-six years I have been designing and constructing waterfalls and ponds the professional way, using 3500 psi concrete reinforced with rebar and coated with an industrial grade concrete sealer. With over 1,900 projects to date, not one has cracked or leaked.
Approximately fifteen years ago, Greg Whitstock of Aquascape Company decided to capitalize on the use of rubber sheeting, a material used to cover flat roofs. He changed the name of "roof liner" to "pond liner" and built a pond in his back yard. He tells the story that he had a cement pond that continually cracked and leaked, so he pulled it out and replaced the cement with this rubber material.
To this day, he instructs his dealers and contractors to tell their prospective clients that concrete ponds crack and leak and cost more to build, and that liner ponds are warranted for twenty to thirty years. Sometimes telling a half truth is the same as telling a lie.
I have ripped out many defective concrete ponds and replaced them with properly installed concrete, constructed with rebar, not with rubber liners as Aquascape does. Why? Because the concrete ponds I replaced were poorly constructed, which is why they cracked. Some were made with mortar mix and chicken wire, or concrete without reinforcement or concrete that contained "cold joints" from pouring the concrete over a period of several days. Plus, some were made with improper proportions of cement and gravel.
If 3500 psi concrete is used with stealth fiber mix added and used with rebar eight to ten inches on center, it will never crack, not even from frost or freezing. On the other hand, what the liner guys will purposely fail to tell you is that the twenty-year warranty for a liner is only against factory defects. What they will not tell you is that liners are vulnerable to many different elements.
Last year I got a call from a client who told me they were buying a home in Rancho Santa Fe, California, and they needed me to look at a waterfall and pond that leaked. They told me that the owners had paid a pond liner company $276,000 to build this water feature. The waterfall measured ten feet wide and fifty feet high, consisting of boulders that weighed between one and five tons each. In less than two months it began leaking and got increasingly worse over the next five to six months. They called the contractor and he came out and did an investigation and pointed out the rat and gopher holes that had been burrowed out at the entrances in the outer bordering rocks. He then explained that the warranty only covered factory defects, not holes made by rodents.
My clients called another liner company to fix the leaks. Because it would be too expensive to remove all the boulders and rocks to examine the liner, they simply mixed up a sloppy batch of Thoroseal and painted around every rock in the falls. Talk about ugly! They charged the homeowner $75,000 and within weeks it was leaking again. But they couldn't get the company to come back. I wonder why?
When they had told me all this, my recommendation to them was to remove all the boulders and create a concrete shell reinforced by rebar. I made the waterfall wider and taller and added a pond with a large tulip fountain at the top. I made the pond at the bottom twice as wide and doubled its length. In addition, I replaced their 2-hp pump with five 3-hp high-efficiency pumps. Plus, I added a 200-watt ultraviolet sterilizer light, a 6000-gallon pressure bead filter, fifty-six 20-watt spot and submersible lights, and an electronic Aquafill auto-level control system. All this was added for $200,000, a full $76,000 less than the liner guy.
Now the homeowners have a waterfall and ponds that will last for decades and require minimal maintenance. What's more, all the rocks and boulders are mortared in place so that, unlike liners, there is no danger of them moving when walked on.
Much of my work over the last 25 years has been replacing leaky liner ponds with concrete, rebar and rocks. And every one of them won their lawsuits against the liner pond contractors, primarily because of their deceptive sales practices. If you are a liner guy, why not start doing it the professional way instead of using shortcuts, and inferior materials and components... the "get rich quick" approach. If you are just looking to do it right, now you know how: reinforced concrete.