How to Dig a Stormwater Pond

Use a backhoe to dig a stormwater pond.

Digging a stormwater pond will almost inevitably involve bank-formation and possibly damming. As such, you'll find yourself in need of some heavy machinery to get the job done in a timely fashion. The process is easy, provided you situate the pond in a geographically favorable area and use simple safety measures. As important as the pond itself, though, is the proper and efficient design of the feeder and drainage ditches.

Things You'll Need

• Backhoe
• Bulldozer
• Heavy clay soil

Instructions

1. Survey the land for an appropriate location. Stormwater ponds can be aesthetically pleasing, but this is not their primary purpose; the pond should be situated so that it offers good drainage to the surrounding land. Therefore, it must be in the lowest topographical point in the landscape to perform this function.

2. Move dirt from the middle of the pond to the edges, using the backhoe. This will help you quickly reach the necessary depth. Consider any secondary uses for the stormwater pond before digging: if fish will be stocked, it must be 12 to 15 feet deep. The banks should be formed with a width/height ratio of 2 to 1.

3. Apply a layer of heavy clay soil to the pond bed and use the heavy machinery to tamp this down. This will aid in retention, which is important unless you specifically desire the pond to drain more readily. In certain situations, such as those where the runoff is likely to be contaminated by street residues, lawn fertilizers or other chemicals, this may be the more desirable option. Check with your local government to determine how to proceed with water quality issues from runoff.

4. Develop a stormwater runoff grid that will deliver excess moisture expediently from the surrounding land. One or two primary ditches should be fed by smaller ditches, all of which will must follow the basic principles of gravity to guide rain water toward the pond. Depending on the size of the pond and the amount of runoff anticipated, one or two drainage ditches will be necessary, and these should meet up with bodies of water capable of handling the excess water.

Tips & Warnings

• Check with your local government office before conducting any project that will affect local waterways, drainage, etc. Heavy fines and penalties may be incurred if a stormwater drainage plan is enacted without permits or government approval.

References

• Penn State School of Forest Resources
• Washtenaw Conservation District