When building a pond, there are various approaches you can take depending on your specific goals and preferences. Whether you're aiming for a recreational space, a visually appealing feature, or a functional pond, there are several primary types to consider. Each class has a unique construction method to help you achieve your desired outcome.
Watershed Ponds
Watershed ponds are created in naturally depressed valleys. By constructing a dam across such a valley, you can collect and store the rainwater that naturally flows into it from the watershed. In concept, watershed ponds are like embankment ponds, but there are some differences in size and primary water source.
Embankment Ponds
Imagine a stream flowing through a small, depressed valley, where the valley is deep enough to store 5 feet or more of water. By building an embankment (or small dam) across this stream, you create an embankment pond. The surrounding land's slope can range from gentle to quite steep, depending on the area.
Levee Ponds
Picture an aboveground pond with walls. These are made by erecting levees or walls around a specific area to contain water. However, since these don't naturally gather water from their surroundings, they require a source of water from wells, streams, reservoirs, or canals.
Excavated Ponds
Think of a generally flat area where you dig a hole to create a pond. Since most of the water capacity comes from digging, these ponds are best suited for places needing a relatively small water supply.
Hybrid Ponds
In some cases, you might find yourself in a moderately sloping area where a combination of digging and dam building works best. The water capacity for such ponds is achieved both through excavation and the construction of a dam. Alternatively, you might excavate a pond in a flat area but need to create additional capacity. Constructing a levee around an excavated pond can meet that need.
The type of pond you decide to build will largely depend on the topography of your location, the tools and materials at your disposal, your budget, and your desired outcome.
Investing in Passive (Water) Income: Watershed and Embankment Ponds
Among the various ponds that one might consider building, the watershed pond stands out for its ability to work with nature. These ponds collect and store water using the natural flow of the landscape, known as runoff. In contrast, an embankment pond is formed by building an embankment (or dam) across an existing stream or other natural watercourse. However, since many states consider natural watercourses public waters, this practice is often prohibited. So, we’ll focus on watershed ponds in this discussion.
Understanding Watershed Ponds:
Watershed ponds take full advantage of the surrounding land's topography. Essentially, they capture surface runoff—water that flows overland without being absorbed into the ground or funneling into established watercourses. The size of the pond and its water storage capacity are fundamentally influenced by the area of land that contributes to this runoff, termed the watershed. Depending on the terrain, sometimes, constructing a single dam may be sufficient for forming a watershed pond. The beauty of utilizing runoff is that it often negates the need for external water sources like wells.
Legal and Regulatory Aspects
Before diving into the construction of a watershed pond, it’s essential to acquaint oneself with legal regulations. In many cases, obstructing streams and springs for private purposes is regulated by the state’s Department of Natural Resources (DNR). However, surface runoff, especially from natural watersheds not yet funneled into established channels, is usually deemed public water, and can often be collected freely. Always consult with your local DNR for helpful information like watershed ratios and specific permit requirements.
Dam Construction and Maintenance
The dam, often the backbone of a watershed pond, requires meticulous planning and professional execution. Employing a qualified professional for its design and construction is paramount. Factors like the soil type, compaction methods, and the introduction of adequate drainage structures play pivotal roles in ensuring the dam's long-term stability.
One critical maintenance tip is ensuring trees or shrubs don’t take root on an earthen dam. Their presence can compromise the dam's structural integrity, increasing the risk of leaks or even catastrophic failure. However, if you’re dealing with an older dam with mature trees, removing them might be counterproductive. Their decaying root systems could potentially destabilize the dam further.
Selecting the Perfect Site
The ideal site for a watershed pond is typically higher up within a watershed. When water is collected early in the runoff path, there is less opportunity to collect silt and pollutants, ensuring a high-quality water source. When choosing a site, look for locations that necessitate minimal soil for dam construction but still offer significant depth—around 6 to 7 feet at the deepest points. Ideally, more than half of the pond should be at least 5 feet deep. The goal is to select an area that maximizes water storage relative to the dam's height.
