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
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.