Cesspool vs. Septic Tank: What’s the Difference?
Wastewater treatment is a critical aspect of public health and environmental protection. In areas without access to centralized sewer systems, onsite wastewater treatment systems (OWTS) such as cesspools and septic tanks play a vital role in managing household sewage.
Septic tanks and cesspools are both types of sewage systems, but they have some major differences. A cesspool is simply a hole in the ground that collects wastewater. A septic tank, on the other hand, is a more complex system that uses bacteria to break down the waste. If you are trying to decide between a cesspool and septic tank for your home sewage system, you should consider both options, but always contact a professional before making a final decision.
What is a Cesspool and What Does it Do?
A cesspool is a system for disposing of human waste used since ancient times. It is defined as a shallow subterranean mostly concrete facility for the disposal of sanitary waste. A cesspool's structure generally comprises concrete walls with an open bottom and pierced sides. Wastewater enters the cesspool via a drain pipe and percolates through it. It's important to remember that while cesspools collect sanitary sewage, they do not treat it.
Cesspools were among the earliest forms of wastewater disposal in America, coinciding with the introduction of indoor plumbing. As urbanization increased, cesspools became more prevalent, particularly in areas without centralized sewer systems. However, due to their limited treatment capacity and potential for groundwater contamination, cesspools gradually fell out of favor. In the late 19th century, cities like Baltimore and Chicago faced significant public health challenges due to the widespread use of cesspools and inadequate sanitation. Today in places like New Jersey, homeowners with cesspools must switch to a septic tank before selling their property.
Concerning its construction, it is a circular hole in the ground lined with perforated concrete or block, similar to a well-liner, but with holes. There is no specific distribution of waste. Household liquid waste is dumped into the cesspool, sludge builds at the bottom, and effluent and scum drain through the openings directly into the surrounding soil.
Cesspool sludge must be pumped regularly to keep the holes open for water flow, and they must be relocated frequently as surrounding soil gets saturated which causes wastewater to begin pooling on the surface of the ground. A modern septic system would likely be installed to replace any cesspool that has outlived its use.
What is a Septic Tank and What Does it Do?
The septic tank is the heart of the sewage system; part of a sophisticated distribution mechanism that sends only the effluent (water) to a distribution box with numerous perforated pipes otherwise called the drain field.
Septic systems in America are a vital part of households’ wastewater management system. It serves as the first stop in the process of treating and disposing of sewage from your home. The tank separates solid waste, grease, and oils from wastewater, setting the stage for further purification in the leach or drain field.
Here’s how it works:
Wastewater Enters the Septic Tank
Wastewater from your home's sinks, toilets, and drains flows into the septic tank. The septic tank is typically made of fiberglass, concrete, or polyethylene and is designed to be watertight.
Separation of Waste
Inside the septic tank, gravity does the heavy lifting.
- Heavier solids, such as fecal matter, settle at the bottom and form the sludge layer.
- Lighter materials, like oils and grease, float to the top, forming the scum layer.
- The middle layer, known as the effluent, consists of wastewater that is free from most solids and grease.
Anaerobic Digestion
Bacteria within the septic tank work to break down organic material. Over time, this reduces the volume of sludge and scum, minimizing the frequency of required septic tank pumping.
Effluent Flow
The effluent flows out of the septic tank through an outlet, which often includes a baffle to prevent scum or sludge from escaping. In septic systems with two compartments, the effluent first moves into the second chamber for additional settling before exiting.
Distribution to the Leach Field
After leaving the tank, the effluent enters a distribution box (D-box). This box evenly channels the wastewater into the leach field, where it disperses through perforated pipes or leaching chambers.
Final Purification in the Drain Field
The leach field uses soil's natural filtration properties to purify the effluent further. The soil removes harmful bacteria, viruses, and nutrients before the water seeps into the groundwater.
Septic tanks must be properly maintained to function effectively. Regular pumping removes excess sludge and scum, ensuring that neither layer overwhelms the tank or clogs the system. This maintenance prevents untreated waste from contaminating the drain field or nearby water sources.
For those considering a septic tank over a cesspool, options include single-compartment tanks or more advanced two-compartment systems designed for improved waste separation. Similarly, septic pump tanks can assist in moving effluent to elevated drain fields when gravity alone isn’t sufficient.
Key components of a typical septic tank include
The development of septic tanks marked a significant advancement in onsite wastewater treatment. The first septic tank was invented in France in the 1860s by Jean-Louis Mouras. Mouras' design involved a sealed concrete tank that allowed wastewater to settle and decompose before overflowing into a cesspool. This innovation was introduced to the United States in the 1880s and quickly gained popularity. By the mid-20th century, septic tanks became the preferred OWTS in many parts of the country.
Here are the key parts of a standard septic tank system:
- Inlet Tee
The inlet pipe brings wastewater from the house to the septic tank. It ensures that the incoming wastewater does not disturb the settled layers within the tank. - Septic tank
The tank itself provides the primary treatment, allowing solids to settle and decompose. - Outlet pipe and sewage filter
The outlet pipe carries the clarified effluent to the drain field. A filter on the outlet pipe prevents solids from escaping the septic tank. - Drain field or leach field
The drain field is a network of perforated pipes or leaching chambers that distribute the effluent into the soil. Microbes in the soil further treat the wastewater, removing most contaminants before it reaches groundwater. - Baffles
The primary function of the baffles is to divide the tank into two chambers, helping to retain solid waste and scum in the first chamber. The baffle includes an opening about two-thirds of the way up, allowing effluent to flow into the second chamber. This design ensures a more efficient separation process within the septic tank. - The baffle is strategically placed at the tank's outlet to prevent solid waste or scum from leaving the septic tank and entering the drain field. Additionally, the baffle directs the effluent toward the outlet pipe, facilitating a steady flow to the distribution box or pump tank.
Cesspool vs. Septic Tank: Key Distinctions
The primary distinction between a cesspool vs. septic tank is that a septic tank is designed to contain wastewater until it can be pumped, while a cesspool drains slowly. Septic tanks need less upkeep than cesspools because they are intended to process, filter, and cycle wastewater, sending treated effluent to a drain field for natural filtration. Cesspools, on the other hand, leach untreated wastewater directly into the soil, leading to more frequent clogs and maintenance needs.
Apart from the fact that cesspools are smaller, there are several key distinctions between them and septic tanks.
- Septic tanks can process a lot more wastewater than cesspools, making them a superior choice for larger homes.
- Septic tanks require less maintenance than cesspools.
- Cesspools are cheaper to build than septic tanks.
- Cesspools have a limited lifespan.
Which One Should You Choose for Your Home?
Cesspool - Pros and Cons
Pros of Cesspools:
- Cost-Effective Installation: Cesspools are more affordable to install than septic systems, making them a practical choice for those on a tight budget.
- Simpler Design: With no need for additional components like drain fields, cesspools have a straightforward design that reduces initial construction complexity.
- Space-Saving Solution: Ideal for properties with limited land, cesspools can be installed in areas where a full septic system isn't feasible.
Cons of Cesspools:
- Environmental Impact: Unlike septic systems, cesspools discharge wastewater without treatment, posing risks of contamination to nearby soil and water.
- Regulatory Restrictions: Many regions have outlawed cesspools in favor of closed septic systems due to stricter environmental protection standards.
- Site Limitations: Cesspools are unsuitable for areas with high water tables or expansive soils, which can lead to contamination or structural failure. Research indicates elevated nitrate levels in groundwater in areas with dense older cesspools.
Cesspools may work well in specific situations, but their environmental limitations and potential regulatory hurdles often make septic systems a more sustainable and compliant choice for modern wastewater management.
Septic Systems - Pros and Cons
Pros of Septic Systems:
- Ecological Benefits: Septic systems reduce pathogens and pollutants in groundwater by dispersing treated effluent over a wide area, allowing the soil to naturally filter and purify the water.
- Durability: With proper maintenance, septic tanks seldom need replacement, often lasting 50 years or more.
- Ease of Maintenance: While both systems require upkeep, septic systems are generally easier to care for and involve less frequent pumping compared to cesspools.
Cons of Septic Systems:
- Higher Cost: Septic systems have a higher upfront cost than cesspools, making them less budget-friendly for installation.
- Space Requirements: Septic systems require additional land for a drain field, which may not be feasible for properties with limited space.
- Regulatory Compliance: Septic systems must meet specific local codes and guidelines, which may require additional inspections or modifications during installation.
Septic systems provide long-term ecological and practical advantages but come with a higher price tag and more stringent installation requirements compared to cesspools.
Regulatory Perspectives of Cesspools vs. Septic Systems
Recognizing the potential risks associated with Onsite Wastewater Treatment Systems (OWTS), regulatory bodies such as the Environmental Protection Agency (EPA) have established guidelines and regulations governing their use. These regulations aim to minimize environmental impact and protect public health.
The EPA has banned the construction of new large-capacity cesspools and encourages the replacement of existing cesspools with more advanced treatment systems. This ban reflects the EPA's recognition of the significant pollution potential of cesspools.
Regulations for septic systems focus on proper design, installation, and maintenance to ensure effective treatment and minimize the risk of contamination. These regulations often include requirements for:
- Tank size and construction: Ensuring the tank is appropriately sized for the household and constructed to prevent leaks.
- Drain field location and design: Ensuring the drain field is located in suitable soil with adequate drainage and designed to effectively treat the effluent.
- Regular inspections and pumping: Ensuring the system is regularly inspected and pumped to prevent solids buildup and maintain proper function.
Tank Depot is Your Best Option for Septic Tanks
America has gradually shifted away from cesspools towards septic tanks and public sewer systems. This trend reflects a growing awareness of the public health and environmental risks associated with inadequate wastewater treatment.
If you are building a new home, your only likely wastewater choices are a septic system or the city sewer system. If you are considering a new septic tank, make your first call to Tank Depot. We offer a huge selection of septic tanks, as well as other water storage options, and guarantee the best price.
Contact us today for more information and the location of a retail store near you.
