If you have a pond on your property or in your community, you may need to dredge it from time to time. Dredging is the process of removing sediment and debris from the bottom of a body of water.
It is important to dredge a pond because sediment can build up and make the pond shallower, which can reduce the amount of oxygen in the water and make it difficult for fish and other aquatic creatures to survive. On top of this, dredging can also improve the appearance of a pond and make it clearer.
But how does dredging a pond work and what should you avoid during the process? To help steer you in the right direction, let’s break down how to dredge a pond.
Step 1 & 2: Decide if animals and water need to be removed.
If you need to drain the pond of water, you may need to remove all animals from the pond before you begin dredging. In this case, animals can be captured in nets and relocated to another area.
This is usually only necessary with mechanical dredging and when you’re operating closer to the middle of the pond. However, if it’s closer to the edges of the pond, it’s usually only necessary to lower the water level as needed.
That being said, hydraulic dredging requires water to still be present. This way, the dredge can float on the water to get to the necessary locations.
The Pros of Draining a Pond Before Dredging
There are a few advantages to draining your pond before dredging. Draining the pond will allow you to work faster and with more ease. It will also give you an opportunity to inspect the liner for any damage that may have occurred as a result of the build-up. Finally, it also allows you to remove any large pieces of debris that may be difficult to remove when the pond is full of water.
The Cons of Draining a Pond Before Dredging
Despite the advantages, there are a few serious disadvantages to draining your pond before dredging. First, it can be stressful for the ecosystem since all of the fish and other aquatic creatures will need to be relocated while the dredging process takes place. As an additional drawback, if the draining is not done correctly, you can encounter major hurdles refilling the pond afterwards (especially in geographical locations where drought conditions or water restrictions are present).
Step 3: Excavate the sediment.
Once the pond is empty, you can begin excavating the sediment from the bottom of the pond. This can be done with a shovel, bucket, excavator, or dredge. The depth of excavation is dependent on how much sediment is accumulated (where the soft sediment and hard pan bottom meet). This is why it’s important to work with a professional since it’s hard to tell how much sediment needs to be removed without correct survey/mapping.
Keep Learning: What is pond dredging and why does it matter?
Step 4: Dispose of the sediment.
Once all of the sediment has been removed, you will need to dispose of it properly.
In some situations, you may want to contact your local landfill or solid waste management facility. They will be able to tell you what options are available for disposing of the dredged sediment. The most common option is to haul it away in dump trucks. However, this can be costly, so be sure to get quotes from multiple companies before making a decision.
Another option is to dewater the sediment and then spread it on agricultural fields as a fertilizer. This is a great way to reduce your disposal costs while also benefiting local farmers.
As a final option, you could also use the dredged sediment to create wetlands or other habitat areas on your property. This is a great option if you have the space and are looking for a way to improve your landscaping. Again, you will need approval from the local authorities before taking this approach.
However, for all of these examples, there should be analytical containment testing performed to ensure there are no contaminants in the material.
EPA states that the owner is responsible for sediments and their contaminants – from ‘cradle to grave’. If the site they dumped was contaminated (even years later), they must be able to prove it wasn’t their sediment.
With private property, in particular, if contaminants are present, they can get into groundwater, livestock feed, other agriculture products, or wash into another water body causing issues. This is why it’s important to have testing completed prior to disposal.
Step 5: Refill the pond.
Once all of the sediment has been removed, you may need to refill the pond with water.
There are a few different methods that can be used to refill a pond after dredging, and the method you use will vary depending on pre-existing regulations and equipment.
Keep Reading: The top benefits of dredging
What to do and not do when dredging a pond
Dredging can be beneficial to the health of your pond and the fish that live in it. However, there are some things you should know before you start dredging. Let’s cover some must-know do’s and don’ts when dredging a pond.
What to do:
- Research what type of dredge is best for your pond. There are different types of dredges and what works for one pond might not work for another. Doing some research ahead of time will help you choose the right dredge for your pond. If possible, consider using hydraulic dredging methods (since they typically have less impact on the surrounding ecosystem).
- Create a plan. Once you know what type of dredge you need, you need to create a plan for how you’re going to use it. This includes where you’re going to put the dredged material and how you’re going to dispose of it.
- Get permits. Depending on where you live, you might need permits to dredge your pond. Check your local laws before you start dredging.
- Dredge during the right time of year. The best time to dredge is during the ‘dry’ season when it rains, which adds water back into the system and extends the life of the dewatering aspect of dredging projects exponentially.
- Hire a professional. Dredging a pond is a big job and it’s not something that should be attempted by someone who doesn’t have experience with it. If possible, hire a professional to help you dredge your pond. A qualified professional can conduct an aquatic site assessment to determine if dredging is the appropriate solution and help you develop a dredging plan.
What not to do:
- Don’t use too much suction. Using too much suction can damage the ecosystem of your pond.
- Don’t dredge too deeply. Dredging too deeply can also damage the ecosystem of your pond and harm the fish that live there.
- Don’t dispose of the dredged material improperly. Disposing of dredged material in an improper way can pollute waterways and negatively impact the environment. Make sure you have a plan for disposing of the material before you start dredging.
- Don’t use unapproved chemicals during dredging or disposal activities. Certain chemicals or products can contaminate the watershed and harm the environment.
By following these simple steps and best practices, you can easily dredge your pond and improve water quality. Dredging is an important part of pond maintenance and should be done on a regular basis to ensure a healthy ecosystem for plants and animals.