Pond And Lake Restoration Step 3: Final Considerations
Regardless of whether you have a “mature” pond or are in the beginning process of a pond or lake restoration, it is critical that you understand there are certain structural, physical and maintenance issues that are of an ongoing nature and need to be always on your “To Do or Pay Attention to” list.
Norman Latona is president of Southeastern Pond Management, which offers services that cover the waterfront of lake and pond management, as well as development. SEPond provides ecosystem analysis, management programs, pond construction and maintenance, liming, fertilizing, fish inventory assessment, electrofishing, fish removal processes, stocking of forage and game fish and more.
Pond And Lake Restoration: The Structural Physical Plant
If you have a pond with a dam and a spillway, if the dam fails then basically you no longer have a pond.
According to Latona, preventative measures center around erosion control, vegetation control, pest control and just simple responsible property management.
“What we look at is best practices for things like erosion control, vegetation control, keeping critters away from the water and keeping the shoreline clean and all of it is just common sense,” Latona said.
While you can have vegetation around your dam it needs to be kept clean and free of trees and woody vegetation whose extensive roots can undermine the dam structure.
“We want there to be rooted vegetation growth because that is what anchors the dirt and helps in keeping erosion away but we don’t want trees and heavy wood shrubs there because those are the kind of plants that put down root systems that actually tunnel into the ground and compromise the dam,” Latona explained. “You should commit to cut them periodically, at least once or twice a year.”
“While woody vegetation and the subsequent roots anchor the soil to some extent and help prevent erosion, they can severely tunnel underneath and even into the dam and if a storm knocks down that tree suddenly you have a big hole that most likely will fill with water and possible result in a structural problem,” Latona further explained. “You want the sides, top and back of the dam to be free of woody vegetation and have the right slope to be able to use a bush hog or other equipment to keep things cut or, if necessary, you can use herbicides.”
In order to be able to manage that vegetation you need to maintain a reasonable slope on both the front and the backside of the dam which is probably a four or five to one ratio resulting in a slope which is gradual and tapered enough to accommodate a tractor or bush hog.
Pond And Lake Restoration: Aquatic Weeds
In terms of aquatic vegetation control, it is a minimum depth issue.
Weeds or any vegetation for that matter need sunlight to grow and the deeper the water the less sunlight penetrates to the bottom to promote that growth.
As a writer/editor aside, believe it or not, that simple fact is a case for liming and fertilizing. If the water has a green tint to it, it is not only plankton rich, which is the beginning of the pond food chain, but the green tint hinders weed growth because it inhibits sun from reaching the bottom.
Weeds grow out of the bottom of the pond. The less sun hitting the bottom the less weeds you will have. Sounds a bit dumb but it is true and that dovetails into water depth as an inhibitor to weed growth. The deeper the water and the greener it is, the less weeds you are going to have because of the tint and and most likely the more fish.
If you are constructing a pond, sculpturing the depth is easily done but, if you have an established pond, water depth is a whole different beast.
“If we can get down to sub three feet of water depth, we can eliminate a lot of the shallow areas that attract vegetation that leads to an owner having to spend a lot of time and money battling these weeds for years to come,” Latona said.
Pond And Lake Restoration: The Question of Erosion
A pond is a “physical plant” and over time, it will show signs of aging and deterioration. Probably the most common and damaging problems ponds have are shoreline erosion and erosion around dams and spillways.
“The pond is obviously going to be the lowest spot and all the water will run to it and that running water will cut its way through the bank. The remedy is to make sure that the banks are properly sloped, seeded, mulched and that there is an established stand of “non-woody” native grasses and vegetation established all the way around the water’s edge,” Latona explained. “Otherwise, you can get water channels and cuts that will deteriorate the shorelines and structure of the pond and it can become quite a mess.”
Latona said that if the pond is big enough and has significant wave action that can erode the banks it may even be necessary to add rock or “rip-rap” to break up that wave lapping action. The question becomes: is adding rock or riprap an end to itself or is it just a protection until the natural vegetation grows to stabilize the situation?
“It is a little bit of both. Rip rap or rocks the size of bowling balls or even larger can help protect the dam, which normally has straight open water in front of it, from the constant pounding from the wind and water, some of which, on larger lakes, may even come from wakes from boats that can result in the cutting and undermining of the soil and ultimately the dam,” Latona said. “Once established, it’s remarkable what vegetation can do in the way of erosion control.”
Pond And Lake Restoration: General Maintenance and Considerations
Latona says that one of the best pond restoration techniques is to keep the shoreline cut and mowed with attention to the thick and heavy wood vegetation and can cause problems down the road. He also added that if you feel ambitious you can have SEPond “Deepen the Edges” which means they can go out up to about 30 feet, rake some of the silt and sediment that is causing shallow shorelines and, in doing so, can have a big effect in controlling pond vegetation.”
The bottom line is that from the day a pond is constructed it is headed towards silting and getting shallower. It isn’t a bad thing; it is just reality and a matter of time, but you can mitigate that by having a corrective maintenance program.
One of the things that SEPond has to offer is being able to cut a “swath” around your pond and even go into the water to trim shoreline vegetation which has a dual benefit of reducing cover that attacks nuisance animals such as muskrats and even snakes.
“We’ve got nice equipment such as rubber track skid steers with big cutting heads that can get right up literally to the water and even in the water in some cases, and just clip that stuff down and just make it manicured,” Latona said. “You can walk around and fish and it looks really nice. There is value in that.”
Pond And Lake Restoration: Nuisance Animals
While they may look like cute little furry animals, muskrats, beavers and even otters (specifically otters if you care about your fish population) are problematic and must be considered when doing pond and lake restoration.
Otters can wipe out your fish population relatively quickly. Muskrats can tunnel and burrow into the dam and create holes and channels that could make your dam collapse and beavers can also burrow into the banks and remove trees that while they may be away from the dam can cause erosion and clog the system. Then there are snakes.
“You can’t eliminate all those animals, but you can certainly mitigate the damage they do and the abundance of them simply by keeping the shoreline area maintained and keeping the dam and the vegetation under control so that it’s just not a free for all,” Latona said.