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Well-built ponds are
beautiful,
easy to maintain, and fun
throughout the year.
by kim j. gifford
EVERY YEAR IN THE UPPER VALLEY when summer’s
balmy temperatures finally arrive, it’s only natural
that people’s minds turn to refreshing thoughts of
water. Swimming pools are often the first thing that
people think of, but they’re often a nuisance to
maintain and lack country charm—and, let’s face it,
summer in these parts is short. For these
reasons—and because the soil in summer is perfect
for digging—man-made ponds have long been a popular
alternative.
When constructed with care, man-made ponds blend in
and enhance the natural environment, and they also
offer a plethora of uses that stretch beyond the
brief summer season—ice skating, fishing, fire
protection, and irrigation to name a few.
While ponds usually require less maintenance than
pools, they demand considerable planning. In fact,
much of the effort that goes into pond construction
occurs before an excavator or backhoe even touches
the ground.
Pond Planning
Before setting off to design your pond it is
important to understand why you want it. A pond’s
use not only determines where you place it, but also
dictates other elements of its design, such as the
height of its banks and the landscaping around it.
Often ponds may serve more than one purpose.
Once you have decided on the type of pond you want,
you can go about choosing where to put it. It’s best
to have several possible locations in case your site
of choice does not test well for soil or lacks a
good water source. It is important that a pond site
contains water-retaining soil, such as clay, and
that it lies near an underwater spring, or a stream.
Tim Matson, a pond expert and author of several
books on pond construction, suggests locating ponds
downhill from houses so that homeowners can glance
out their windows and observe the ever-changing face
of the water. He also points out that houses
situated below dammed ponds are vulnerable to runoff
or flooding.
Before beginning construction, check with your local
and state governments to see if a permit is
required.
Pond Construction
Digging a test hole to the proposed depth of the
pond will allow you to determine if a site has the
proper soil composition. If the soil is good, clear
the site in preparation to dig. Many people hire a
contractor who owns the proper equipment to do this.
Throughout the construction process, make sure your
contractor is following the specifications of your
design plan.
Essentially there are two types of ponds: excavated
ponds, which are created on flat areas; and
embankment ponds, designed for sloping terrain.
Excavated ponds can be fed by surface runoff,
groundwater, or a combination of both. Regardless of
its type, whenever possible you should create a
natural shape to your pond rather than a perfect
oval.
According to Matson, embankment ponds require an
earthen or concrete dam “on the downhill side of a
slope or stream to hold back the water,” and a basin
along the uphill side to trap any sediment that
could be carried into the pond by run off. The
necessary height of the dam and depth of the basin
depends on the slope and depth of the pond.
In Matson’s DVD, The Earth Ponds DVD: Design and
Construction, he states that poorly designed
spillways for excess water “are one of the most
common problems in pond construction.” Spillways are
essentially dug-out channels extending from the
shore of the pond. Spillways are favored by most
pond designers because they are natural looking; and
they are generally used for excavated ponds.
Some embankment ponds employ spillways to maintain
proper water levels, but most rely on pipe
overflows, which are laid into the mound of the dam.
While pipe overflows tend to be more conspicuous
than spillways, they allow for a greater level of
control.
Ultimately, your site will dictate the design of
your pond and the type of spillway or pipe overflow
it requires.
Pond Maintanence
When it comes to maintaining your pond, you should
carefully monitor its inflow and outflow areas as
well as the shoreline. If either the inflow and
outflow systems clog, the water could spill over the
edge and cause erosion.
A buildup of silt and sediment within the pond
itself can also lead to problems. After many years,
some ponds need to be dug out and cleared of this
matter before it displaces the water entirely. If
untended to for too long, a pond may dry up, and
become a marshy area overridden by plants.
You should also keep your pond clear of too many
nutrients and phosphorus to prevent an overgrowth of
algae that can make a pond unattractive and
unsuitable for swimming. To accomplish this, make an
effort every few months or so to clear smaller
debris such as decaying leaves.
While experts recognize the necessity of these
measures, they usually suggest a laissez-faire
approach on a day-to-day and week-to-week basis.
According to James Kennedy, landscape architect and
wetland specialist from Etna, New Hampshire, “It’s
what you don’t have to do that counts… You don’t
want to mow the lawn too close to a pond or use lawn
fertilizers too close to a pond.”
Kennedy also discourages homeowners from
constructing sandy beaches near the pond’s edges.
“If you want a pristine environment to swim,” he
concluded, “build a swimming pool.”
Before you go that route, however, make sure you’re
ready to maintain the pool. Otherwise you’ll end up
with a pond after all—a pond that won’t blend in
with, or become a part of, the natural ecosystem—a
pond you won’t be able to use throughout the year.
Uses for a Pond
Recreation. Since the
size and water requirements for swimming are similar
to those for fishing, consider stocking your
swimming hole with rainbow trout. According to
Vermont Pond Construction Guidelines, a pond for
fish needs to be seven to ten feet deep over one
quarter of the area of the pond. Ponds intended for
swimming should be six to eight feet deep in the
center.
Irrigation. Ponds can
serve as a valuable water supply for your crops.
However, you will want to ensure that the water
capacity of the pond is sufficient to meet crop
requirements. In The Earth Ponds DVD: Design and
Construction, Tim Matson states that while
irrigation needs vary, crops on the average need one
inch of rain a week. This requires at least 25,000
gallons of water an acre.
Livestock. An
irrigation pond may also be used to water livestock.
Some farmers allow livestock to drink straight from
the pond; others choose to fence off the pond and
pipe the water to a nearby pasture or dispense it
through a trough. The latter eliminates a chance of
waste contamination and erosion.
Fish Farming. Fish
farming has become increasingly popular with the
decrease in fresh water fish due to land
development. According to Pond Design, Installation
and Maintenance, a guide by the Merrimack County
Conservation District, “a properly built and managed
pond can yield 100 to 300 pounds of fish annually
for each acre of surface water.”
Fire Protection. Live
in a rural area? By placing a pond close to your
house and installing a dry hydrant or pump and hose,
it could save a life or your property. If you’re
uncertain as to what type of setup you need, consult
your local fire department. If you are designing a
pond for this purpose, it should hold at least
60,000 gallons of water.
Waterfowl/Wildlife Pond.
Waterfowl and wildlife are frequently attracted to
ponds. Ponds created with the express intent of
hosting wildlife should be no deeper than three to
five feet, as many species like to feed along the
bottom.
Increase Property Value.
A well thought out and constructed pond will
increase the value of a property. Not only for it’s
many uses, but for aesthetic reasons. |
