Earlier this week, I talked a bit about the advantages of building a pondless waterfall feature. Now, while this is a great way to avoid some of the pitfalls of building a full pond with a waterfall, it’s simply not what most pond owners want. You want the whole shebang, a nice pond full of fish and plants being fed beautifully by a babbling waterfall over those awesome sandstone rocks that you’ve been looking at almost weekly at the home improvement store.
One of the biggest concerns with a waterfall is how notorious they are for losing water. It’s not, however, that difficult to avoid much of this with a little design wisdom before you start digging and a bit of maintenance and fine-tuning.
First things first: use a waterfall box. They’re not that expensive, and they do wonders for ensuring a good, leak-free connection into your pump line that won’t break down over time. Plus, it makes filtration easy and makes it easier to build the waterfall in the first place, as the feeder area is often the most difficult part of the waterfall to get just right.Don’t be stingy with or, worse, skip the liner under your waterfall. Placing a good liner base under the rocks of the waterfall that is continuous along the length of the waterfall and extends out beyond the side edges of the expected stream route. This liner will catch the water that will eventually leak through your stonework at some point and allow it down into your pond.
Expect splashing, and design around it. Some splashing is not only expected, it’s part of the point of the waterfall. When laying out your waterfall, try to work out ahead of time where the splashing will be worst, and plan it such that it doesn’t splash out of the pond, but further down into the run of the waterfall or into the pond. This can save you a ton of water loss, and isn’t that difficult to do.
All of the splashing can’t be anticipated, of course, but even after the pond is built, you can fine-tune the falls to a surprising degree with careful placement of loose rocks after the fact. This will not only allow you to get exactly the falls you want, but also give a more natural look to the whole pond and give you options to change your pond over time. Trust me on this one; you want to keep some of the rocks that you use for the watercourse aside to use loose later on.
Finally, one of the unexpected culprits of water loss in a waterfall is bordering plants. My mother’s pond was experiencing way, way more water loss than it had over previous summers, and we were worried that a leak had developed somehow. Fortunately, before we started pulling things up to look for the leak, we realized that some tendrils of ivy that had grown into the watercourse were to blame, sucking up a stunning amount of water. Maintain your waterfall with this in mind and you can keep a lot more water in your pond.
Another important thing to keep in mind when you’re designing your pond is that you have to choose your pump a bit differently when building a pond with a significant waterfall. Specifically, you have to factor in the elevation gain of the watercourse. A pump has to work harder to pump water uphill, so your GPH (gallons per hour) will be different depending on the elevation gain. Measure this carefully before you buy a pump. Your pump’s producer or retailer should have an easy chart to show the pump’s effectiveness over different heights.
And, while it’s sort of Pond 101 stuff, it’s also worth mentioning that you should have your pump at the opposite end of the pond from the waterfall to maximize the circulation route of the water for a healthy pond.
Speaking of pond health and waterfalls, they’re a great way to aerate your pond, but you might not want to overestimate how much oxygen is getting into your pond from the waterfall. Specifically, the larger your pond is, the higher the waterfall would need to be to effectively aerate it alone. This can quickly get impractical with a deeper pond, so don’t be afraid to use an aerator in the deepest part of your pond to keep your pond as healthy as possible.
This all may seem like a lot, but most of this is just a little bit of thinking things through before you build the pond, and I assure you that if you design your waterfall carefully, you’ll be happy with the result. Nothing beats the feeling when you first turn the pump on and watch the flow of water over your hard work.