The Prudent Use of Water
for Ponds

by David Curtright
Escondido, California USA

Originally published in PondBiz Magazine
November December 2008, Vol. 13, Issue 5/6

Given the current situation regarding water usage in much of the world, the fact that we engage in a pursuit that frequently involves the use of large amounts of water means that we need to be especially aware that this is an extremely important issue in our modern, warmed-up world.

This is less a problem in some areas than in others. The pond owner in Iowa, or Louisiana, for instance, has completely different issues to consider than the pond owner in southern California or Nevada. Two of them get washed out every summer by rain-swollen rivers, or worse, while there are times when the others would be happy for a mere cloud in the sky. A 1" (2.5cm) rain in the midwest soaks into the ground, joining the last 1" storm, and feeds the streams and rivers for weeks, while a 1" storm in some parts of California runs down gullies and canyons, washing cliffs and houses into the usually dry river bottoms, and is completely gone in a few days. Usually, though, the rain does not come down in such quantities.

The reason that this is such an important issue in many parts of the US, especially the southwest, is that the fragile water systems that support life in these areas are being taxed to their limits of sustainability. If the current trends continue as they have for the past few decades, the shortages of today will pale in comparison to those of the future. The Environmental Protection Agency is now considering limits on water usage, and many municipalities are considering, or have already enacted, ordinances that limit water for non-essential uses. The expense of, and political impediments to, getting more water are increasingly intractable problems, so these legislative measures will become more and more common. And, perhaps, so it should be.

In my area, where farmers are having trouble feeding crops, the amount of water used on lawns, for instance, is absolutely unconscionable, and its use as landscape features should be curtailed. Additionally, swimming pools should be limited, and ponds need to be looked at, as well. For those who want a lush lawn in Las Vegas, Nevada, I say, forget it or move. Our water is too precious to dump it onto the ground for the sake of large swaths of non-native plants. Of course, the industries affected by any such restrictions will object to them, and declare that the jobs that their industries produce depend upon there being no restrictions, and how can we be so unfair and so obtuse? The time may come when such arguments will necessarily fall upon deaf ears.

So it follows that we have a responsibility to avoid wasting water. Not only is drought a problem in many parts of the world, the matter of run-off, whether it is because of pollutants in the water or because of storm drain capacity issues, is equally important. Many communities have begun to keep track of these things. Some of my clients with particularly large estates have been spoken to by the water resources people about their water consumption and run-off.


In an average pond there are many opportunities for water loss. Any stream or pond, liner or concrete, can lose water through cracks in the former case, to punctures in the latter, and to overflows in both. Evaporation can also be a huge issue. Traveling in Florida some time ago, I was amused to hear some residents complain that the relative humidity got down to 20% (!) sometimes. In my neck of the desert, it gets down to single digits, often for days in a row. A pond with an active waterfall or fountain, especially a large one, can lose inches per day to evaporation or mist in such a climate. Due diligence includes regular examinations of our systems and how we use them.

I have been in the pond maintenance business in San Diego County, California, for almost 30 years. I generally mind my own business, I do not know most of the local pond keepers, and I do not go to meetings usually. I am known by more people than I know simply because I have been around for so long and I give lectures. As I encounter ponds and their owners, either through references or by accident, I learn things about some of my competitors, including something of the methods used by some of them as they maintain their clients' ponds. One thing that stands out more than any other thing (other than their dependence upon bottled bacteria and enzymes) is their profligate squandering of water. Through back-flushing filters and vacuuming the bottoms of ponds, they dump unknown amounts of water onto the ground for no good reason. Ill-trained "technicians" know no better, and their employers lack control because they are usually absent.

In one instance, I had just undertaken the maintenance of a pond on a large estate. The owner came out to ask me if I would mind looking for the leak in the pond. My inquiries eventually revealed that she had previously hired the same company that my current helper used to work for. He had already told me that they were a vacuuming company, and that they knew no other method for removing debris from a pond. This is a 60,000+ gallon (227,000+ liter) pond, with a lot of debris. As it turned out, they were pumping water out of the pond and directly into the storm drains. It was enough water to run the household bill up from $500.00 per month to $3000.00 per month! This represents tens of thousands of gallons of water per month. In another case, part of a private golf course was washed out by the excessive back-flushing of a large filter.

I learned my business during a time in San Diego of such severe drought conditions that the large storm that finally broke it was called the "March Miracle", and is still remembered by those who were here. It got to the point where it was illegal to fill garden ponds in some areas. Fountains, pools, and lawns went dry. Trees died. During that time I learned that the best way to remove debris from a pond is to get in with a net and remove it, while leaving the water behind. I use nets that are fine enough to catch most of the debris, but coarse enough to move through the water easily.

Before I get into the pond, I sweep the bottom with my net and a pole handle as carefully as possible, knowing that the material will never be as well concentrated as it is when I first approach the pond. Once I begin to walk around in it, I have the net ahead of my feet so that it can pick up material. If I move ahead of my net, or move my net carelessly, I mix water in, and guarantee that I will be able to remove less of it in the end. This is OK because it is never necessary to get it all out, but I do like to get what I can. Each net full is drained of water and the solids are dumped onto shadecloth and allowed to drain for as long as possible before I move it away from the pond in 15 gallon (57 liter) containers. Whatever small amount of water we lose is nothing compared to the amount wasted by those who depend upon their vacuums.

Other water-wise maintenance methods can be adopted to reduce water loss. A common opportunity to waste water is in the back-washing of pressurized filters. In older filters, I always open them up, remove any accumulated material, and stir up the top of the medium before I turn the pump on, and I watch what comes out. As soon as the water clears, I do it again, and repeat until I get an acceptable degree of cleanliness. Merely turning the valve to "Backflush" and walking away is completely wrong. It is nice to change water, but we need to minimize how much we change. One way to mitigate the loss is to use the pond water in a garden area. I try to dump it into some aspect of the landscape, such as orchards or lawns, to avoid dumping it down the drain.

Another way to save some water is to use two-speed pumps. The pond can operate normally at low speed. Filters will stay alive, plants will remain healthy, etc., but when the owner wants more water for a back-flushing, or when he is entertaining, he can turn the pump to high speed. This reduces losses to the air through falls and fountains.

Replacing water that is lost is an issue for those who have no automatic fill lines. They must pay attention to where the water level is and then keep the pond full with the garden hose. This seems innocent enough, but left to its own devices, ignored and forgotten by the pond keeper, it can waste more water than most things. Each of us has forgotten hoses and come back hours later to find water on the ground and sometimes a lot of dead fish. It kills me whenever I do it, and you would think that after so long in the business and even longer in the hobby, that I would have figured it out by now, but I frequently walk away from hoses. I have found that I lose less if I don't turn it on fully.

One way to minimize what we have to dump from a pond is to not stock it with so many fish that maintenance becomes an issue. If the pond builder or a book that you trust tells you that your pond will hold 10 fish, stop at 6. The closer you get to a full load, the more maintenance the pond will need.

Of course, a lot of water is lost to leaks. Many people can have leaks for months before they realize it, and for that reason, I recommend to people with automatic fill valves in their ponds that they turn the thing off a few times per year to see if they lose water. If they do, then they know that they have a problem to solve, and if not, they can relax. Many people miss obvious clues such as an area adjacent to the pond where the weeds grow particularly well, or permanently soft areas. I have a pond on my route in which the fill line is in the skimmer, behind the skimmer basket. When the basket is full, less water flows through it, and the fill line gets a spurious reading and tries to fill the pond, causing water to overflow the pond and go to waste. This is a design flaw that should be avoided.

Some leaks are easily fixed, while others are not easy at all. The first step is to fill the entire system and to turn everything off. A check the next day might reveal which area is leaking, be it a pool in the waterfall, or somewhere in the main pond. If a pool has lost water, then allow the water to go as low as it will go. The water line at its minimum will be at the level of the lowest leak. Seeking leaks out can be tedious but is necessary.

If no water was lost, then turn the falls on and see what happens. If water is lost, inspect any area that has water only when the pump is on. It might be a spot where mortar has separated from a rock, or where a part of the liner has been pushed down for some reason. Plant roots, which can separate stones from mortar, puncture liners, and deflect water flows, and heavy feet are usually the culprits.

Should a leak be found, it is important that it be fixed. Solving plant related issues can range from trimming away extra material to patching large punctures caused by Canna, Papyrus, or Ginger roots. Removal of the plants and simple patches will usually solve the problem, although achieving true cleanliness and ideal conditions for patching can be difficult. If it is not too much work, laying a new piece of liner over the affected area from the top of the system to just below the leak will solve the problem most reliably. Leaks in concrete systems can be patched with various concrete patching products.


One of the most important things that has occurred to me while thinking about this article for the past few weeks is just how difficult these problems really are. It is easy to say that anybody who does what is environmentally unsustainable should just go and find something else to do or somewhere else to do it, but it is never as easy as that. In my own case, I admit that I am in an essentially unsustainable business, and that I should probably think about doing something else, but this is what I do, and this is where I grew up. The ponds exist and they need maintenance. I can empathize with those who are reluctant to leave areas where the traditional industries are moribund, even though that is not the case here yet. This is where most of the things that I hold dear in my life exist, so I am not about to move away. I have joked about why a guy who likes aquatic plants grew up in a coastal desert in California instead of on a swamp in Florida or Michigan, but here I am, and here I shall stay unless I can't for some compelling reason. In the meantime, I will drill a well, do what I can to save water, encourage others to do so, and will be a leader in the cause to help pond owners save themselves from their own, and others', water wasting ways. 

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