top of page
  • Writer's pictureIn-Pipe Technology

How Biosolids Are Building Healthier, Sustainable Soils

Biosolids, otherwise known as natural waste. It’s not something we think about often but at the same time, it’s responsible for keeping us in food and providing a variety of other useful resources.

These solids are nutrient-dense compactions of organic fertilizer produced from the materials removed during wastewater processing. You can compare this process to having a compost heap on a smaller scale - you add food and garden waste which turn the soil into a source of nutrient-enriched soil.

Why do this in the first place? Well, we know that regularly farming the same piece of land leads to the decrease of essential minerals in the soil. In order to use the same soil for years to come, we need to re-enrich it with the right balance of organic matter like biosolids.

Since these biosolids mostly come from us in the form of waste, they already contain the right nutrients to make for great plant growth. In comparison, chemical fertilizers are less encompassing and can actually be dangerous to the environment. Chemical fertilizers require much more energy to be produced which leads to further pressure when it comes to global warming.

But how do we know that biosolids are truly safe to use? And how can we know that this method will help us to produce healthy crops for decades to come?

The Basics Behind Biosolids

As mentioned above, biosolids refer to the waste of humans and animals that are commonly caught up in wastewater collection and then processed before being reused in the environment. The wastewater treatment process sees the solids being removed from the liquids, and then the solids undergo further treatment to become semi-solid and nutrient-dense biosolids.

These biosolids, once they’ve undergone all the necessary steps in the treatment plant, can then be used according to federal and state requirements. Some examples of these requirements include agricultural use or land reclamation which is common in mining sites. This is because, when applied correctly, biosolids hold benefits like:

  • Increasing nutrients

  • Improving the soil structure

  • Water reuse

  • Land conservation

  • Reduced demand on non-renewable resources

  • Decrease in the need for chemical fertilizers

Biosolids are being touted by many experts as the future when it comes to food production and supply. Right now, the United States is one of the most food-secure locations in the world. The problem is climate change - rising temperatures, land erosion, pollution, and other endangering factors may very well threaten the future of food production for the entire globe by the year 2080.

This means that before we get to the point where food security becomes a question, we need to start being proactive about our farming methods and how we approach sustainable agriculture.

What About The Odors That Come From Biosolids?

Now it’s very true that if biosolids have been used to fertilize land in your area, you’ll be able to tell by the smell. Biosolids are known for having a distinctive odor smelling similar to ammonia or other sulfur-based compounds. This can be intensified based on the general environment - high wind speeds, humidity, or temperatures can drive the odors to new heights.

While annoying, these odors pose no risk to human health or the environment and they typically pass on their own within a day or two.

Guide To Biosolids In Land Use

There are a few different uses for these biosolids, and we’ll go over them in more detail below:


The agricultural sector is one of the most prominent users of processed biosolids, which also means that it has been highly regulated. Regulation 40 CFR Part 503.14 sets limits on the amount of nitrogen and other naturally occurring chemicals that can be added back to the land. At present, this practice is used in every state across the country.

The levels needed in the soil will be dependent on a variety of factors - what type of crops are grown there, the location, and general soil characteristics will matter too. The use of biosolids drastically reduces the need for chemical fertilizers that have long-term implications for the environment.

Land Reclamation

Since biosolids are able to return key nutrients back into the soil, it makes sense that they are used for land reclamation. Take mines for example - once all of the minerals have been extracted from the ground, the soil has long been stripped of the ability to sustain vegetation.

By reintroducing biosolids to the area, it’s possible to encourage new plant growth while reducing the toxic chemicals left in the soil. Biosolids have also been used in situations where the soil has eroded or been damaged to the point of having almost no topsoil.

Forestry Support

Biosolids are good for more than just the soil. When it comes to forestry and timber, biosolids have been found to support faster timber growth.

This knowledge and approach are invaluable to individuals and companies that are working on reforesting deforested areas.

Residential Use

You might not realize this but biosolids are even available for use by the public. The ones that meet requirements are allowed to be sold by hardware or garden stores, or you may even be able to acquire them from your local wastewater plant.

Industrial Purposes

Some biosolids are also used for industrial purposes. Biosolids can be refined into what is known as a “sludge” which an increasing amount of companies are using as a source of power.

How Safe Are Biosolids Really?

Considering the nature of these biosolid materials, it’s key that all of the pollutants and potential risks are evaluated. The Environmental Protection Agency (EPA) has recorded a list of contaminants that have occurred over the years. It spans over five hundred entries. This list is also updated every two years with additional regulations being created if those pollutants prove to be harmful to human health.

That pollutants can be found in biosolids is well-known. What is not known is where they will strike or when, which means that every wastewater treatment plant has to have rigorous testing methods in place. Not every pollutant will be present every time, and just because there are pollutants present doesn’t mean that there is an active risk to the public or the environment.

What typically happens is this: the wastewater treatment facility will pick up that there are elevated levels during standard testing procedures. Depending on the type of pollutant or high concentration of chemicals present, the facility will ensure that the biosolids undergo secondary and even tertiary treatment before they are retested and considered safe for the next steps.

Another thing to bear in mind is that because biosolids are so heavily regulated, they have been studied more than any other type of fertilizer by government agencies and academics alike.

Options For Safely Disposing Of Biosolids

A key question that needs to be asked: what happens if we need to dispose of biosolids, or we end up with too many?

The answer typically depends on the community. Other than creating landfills for the biosolids (landfills that still support vegetation growth), or being used for land application purposes these processed solids can also be incinerated.

The point is that dealing with biosolid disposal is less intense on the environment than it is to deal with harsh chemicals or other toxic pollutants.

The Challenge Of Biosolid Compliance

As mentioned above, biosolid use is heavily regulated. For wastewater plant operators, this can be a headache - slightly elevated levels quickly lead to non-compliance and fines that can put you in the hole financially.

Whether the blip was caused by a new industrial user that made a significant dump into your system or a change in the weather, you have a list of adjustments you can make to stay within permit standards. And keeping to those standards can cause you to purchase expensive treatments that put further strain on the plant’s budget.

Your best option as a plant operator is to find a proactive approach that helps you maintain the right levels from the inside out. With In-Pipe’s wastewater nutrient removal solution, you can create an extra treatment step by using your entire collection system to build the health of your microbial community. Harnessing the biological reactions that are already happening upstream can give you a much better result – a cost-effective and more predictable effluent compliance program.

In-Pipe Technology offers an innovative natural biological solution to the problem of fluctuating levels threatening your compliance and permits. Unlike other treatment processes, In-Pipe’s product starts working the moment waste enters the collection system, turning it into an efficient bioreactor that keeps on working until the end stages of wastewater in-plant treatment.

The Difference In-Pipe Technology Makes

In-Pipe will continually put highly efficient bacteria in your system well before the wastewater comes into the plant. The collection system will reach its full potential as a large biological reactor, which can lead to additional plant efficiencies and cost savings.

Some of the major benefits include:

  • Solids can be broken down into more readily biodegradable food sources for the bacteria, reducing important sewer organics by as much as 40%.

  • In-Pipe organisms can feed off of either oxygen or nitrogen, and do so more efficiently than other naturally occurring bacteria.

  • Improved nutrient production means that the plant can cut down on buying additional materials for treatment like carbon, saving even more for the facility.

  • The organisms brought by In-Pipe come straight from the soil, meaning they’re more environmentally friendly than the use of chemicals which can wear down your systems.

Where In-Pipe goes even further is in customizability. We know that not every wastewater treatment plant is the same, so we pride ourselves on tailoring our solutions to your plant’s specific needs.

If you’re facing permit violations or just day-to-day challenges trying to keep your nutrient balance, learn more about In-Pipe’s innovative solution that uses your entire system as a solution.

12 views0 comments


bottom of page