Wastewater Lagoon Sludge Control
As we discussed on our Wastewater Lagoon and Pond Odor Control page, an accumulation of sludge on the bottom of your pond or lagoon is a probable cause of an odor problem you may be experiencing. It is vital that the operator have a lagoon sludge control plan in place.
How can you tell if there is a thick sludge blanket on the bottom of a lagoon or pond?
If a pond’s sludge has never been addressed before and odor is present, chances are there is too much sludge on the bottom. Aside from more visible sludge on the bottom of the lagoon, there are a few ways to find out if there is a large accumulation on the bottom.
Measure with a sludge judge
A sludge judge is essentially a long pipe that is lowered into the water and pushed all the way to the bottom. As it passes through the sludge blanket, a core sample is taken and can be measured to determine the thickness of the sludge blanket.
Gasses released from anaerobic digestion will increase as a sludge blanket thickens. The more sludge you have, the more odor is produced. If you have noticed increasing odors over the years, this could be a sign.
As gasses are released from anaerobic digestion in the sludge blanket, pieces of sludge will break loose and float to the surface. Once on the surface, this sludge will not have any water to cover it and will produce more odor.
Water Color / Overloaded System
A wastewater lagoon or pond should be sparkling blue. Green or brown colors indicate low dissolved oxygen (DO) levels. Low DO levels can be due to an overloaded system. Algae growth is another sign. A thick sludge blanket can cause an overloaded condition because it will decrease the hydraulic capacity of a lagoon or pond. If a pond is designed to be 10 feet deep but has 1 foot of sludge on the bottom, 10% of the pond’s design hydraulic capacity is lost to the sludge. With less capacity, the pond is essentially smaller and cannot treat the same amount of wastewater it used to.
Wastewater Lagoon Sludge Removal
Let’s say you’ve determined that you have too much sludge on the bottom of your lagoon. Now what do you do? Here are your options:
You can pay someone to come out and mechanically scrape out the sludge from the lagoon. The sludge is then transported and disposed of at a landfill or land application facility. This is typically the most expensive option costing tens of thousands of dollars even for smaller systems. This would be a last resort for a lagoon that is overrun with sludge and physically removing the sludge is the only option.
Keep in mind that this will remove the sludge that is present but will not solve the problem that created the sludge blanket in the first place.
Bio-Enzymes and Microbes
Bio- Enzymes and Microbes which consume sludge can be added to the lagoon. Over the course of a few weeks, the sludge blanket will decrease as the microbes do their job. Once again, this option does not address how you got in this situation in the first place. This option is best implemented with the next option as part of an overall lagoon sludge control strategy.
Aeration and Mixing
Aeration is a key part of a lagoon sludge control plan. When you aerate a lagoon, you are putting more oxygen in the water. The bacteria that consumes the nutrients the treatment process is trying to remove needs a healthy supply of oxygen to do its job. Proper aeration will help ensure that the bacteria consume the maximum amount of nutrients possible. Less nutrients left over means less sludge. Proper mixing of a lagoon or pond will break up existing sludge accumulation and keep sludge in suspension. Sludge that is kept in suspension cannot settle to the bottom and accumulate. By breaking up the sludge blanket, oxygen can be reintroduced and the sludge can be consumed by bacteria.
Let us help you!
At Clear Water Supply, we offer a full line of Waste Stream Technologies solutions for wastewater lagoon and pond operators and owners to solve their odor control problems. We are not out to just sell product. We want to develop relationships and work with each of our clients to make sure they have exactly what they need to solve their current problems and avoid future ones.