Recent work on big ponds (1-10 acres) confirmed for me that handling water quality and plant problems in large water bodies can be difficult, expensive, extremely long term, and sometimes near impossible. Often the best solution is to concentrate on one (or a few) manageable areas, where excavation, clean outs, plant control, shore repairs, etc, can be done one area at a time. Not only can this be the most practical approach, but results may be quickly achieved, and with a feeling of accomplishment you wouldn't get trying to tackle a big pond all at once.
One alternative to big pond problems is...the small pond! In my first book, Earth Ponds, The Country Pond Maker's Guide, I quoted an ancient Chinese poet gazing at his small meditation pool: "Who says you can't make a pond out of a bowl?"
The truth of this comment is borne out by the tremendous proliferation of small garden and fish pools over the past forty or so years, from DIY projects to six figure landscape features with elaborate stonework, waterfalls, hybrid exotic fish, fountains, etc.
But you don't have to go overboard to build a small pond. In fact, keeping it simple is one of the key attractions of small pond creation.
Here are some of the main considerations when building a small pond.
Is It For You? Who wants a pond anyway? Well, building small and low budget is a great way to find out if owning a pond is really your thing. Building small allows you to explore a bit of your terrain and learn its natural water capacity. Will your water table support a pond, or will it need supplementary water? Does the soil have water retention qualities? How deep can you dig?
Often a small pond is created as the first stage of a larger pond development. It's called a test pit. Sometimes test pits are as small as the width of a backhoe bucket. But why not make it bigger, say fifteen to twenty feet across, and call it a small pond? You'll learn a lot about your potential for a larger project, and in the meantime have yourself a mini-pond.
If soil or water supply is problematic you may learn ways to add supplementary water. Or install a clay or membrane liner. Maybe both.
The Law. Building big ponds often requires checking into wetland regulations and zoning laws. Depending on the pond size and location, you may need a permit from town, state, or federal government. But a small pond often ducks wetland laws. Check with applicable agencies to be sure.
Do It Yourself. I've seen people dig small ponds by hand (see Earth Ponds Sourcebook), use a backhoe on their tractor, or hire/rent a backhoe or excavator. With a machine a small pond can be dug in a couple of hours, certainly less than a day. You'll want to be sure there is access for the machine to get to the work site. Make sure you have plans to dispose of or stash the excavated material; it may be needed later for shore touchup work or to refill the hole if the project doesn't work out.
Water Supply. It's often pretty easy to keep a small pond full. If ground water isn't doing the job, supplementary water may be added from a well, roof catch, watershed runoff, or a nearby spring or other natural water source. Liners can reduce or eliminate the water demand, depending on liner material.
Water Quality. Keep in mind that your pond is not a swimming pool with chlorinated water. In summer small ponds may tend to heat up due to shallow depth and low volume, and warm ponds are prone to algae, weeds, and clarity problems. This can be overcome with aeration and circulation, and/or supplementary cool water. If fish are stocked and fed, the extra nutrient load can affect water quality. Aeration may help here too. Or removing fish. The good thing about small ponds is that water quality can be readily varied by experimentation. Trial and error is easier in a small pond than a big one. And algae and weeds are often easy to remove manually.
When I think of small ponds I've known I recall a trout farm with a field full of mini earthen pools that were connected and stream fed from one pond to the next, and stocked with a variety of trout species and sizes. Small ponds often work well for aquaculture. Another small pond was dug exclusively to create a water supply for garden irrigation, another to feature flowering lotuses and water lilies. One was long and narrow due to space constraints and benefitted from an aeration system with a single perforated diffuser line the length of the pond instead of a single air outlet. And of course small city park ponds where kids sailed their miniature schooners and rubber ducks. Plus one just big enough so when it froze in winter it was perfect for a young girl to learn figure skating.
The world of small ponds is a big one, with a huge amount of books, magazines, websites, and videos for research, how-to, and inspiration. Dig in.
Topics vary from month to month and provide great information when researching where you want to build a pond, or how to keep it clean. Other areas of interest are pond use for more than swimming, and how to keep fish happy in your pond.