The term lagoon can apply to both small-scale waste ponds and large, commercial, sewage treatment plants. Confusing the two scales of sewage treatment will result in inadequate processing for commercial demands or oversized and costly treatment for residential purposes. Each type of lagoon requires a different approach to dealing with waste. Depending on how much waste you’re processing and the preferred method for discharge, you’ll need to choose between residential and commercial sewage lagoons before building the ponds. Don’t start the material selection or sizing for the design until deciding on its scale and purpose since these questions inform your final choices.
Residential sewage lagoons and cesspools only need a fraction of the size required for a large scale and commercial project. Even when a lagoon is serving an entire community, sharing a common sewage system, it’s usually under an acre in size. Waste treatment plants for entire counties and cities can require numerous ponds, stretching multiple acres each, to provide enough volume and evaporation for the steady supply of sewage. There’s no need to oversize residential sewage lagoons since they’ll evaporate too quickly for proper waste processing.
Levels of Processing
Commercial wastewater treatment ponds and lagoons typically aim to bring the discharged liquid as close to clean water as possible. In some areas, wastewater is even being filtered to the point it’s drinkable again. Residential sewage lagoons tend to rely on evaporation, rather than any specific discharge, so it’s generally a one to three stage processing system. Using a septic tank before the lagoon allows for settling of solids, but some systems only rely on a single sewage pond with a direct connection to the home. In contrast, commercial systems need multiple interconnected ponds and tanks to handle the various stages of processing and polishing so the discharged water has no negative effects on human health or the nearby environment.
Eventual Use or Discharge
The desired use for the finished wastewater or the method of discharge plays a large role in system design. For residential lagoons, discharge and reuse are rare and discouraged in most areas. The risks of trying to irrigate with wastewater is too high in an occupied area. Yet, commercial wastewater plants produce too high of a volume of water to simply store it all and wait for evaporation. In order to keep up with the constant incoming flow, it’s essential to plan for discharge or reuse in these designs.
Covered vs Open Air
Sewage lagoons built for residential use are almost always open to the air. This is because they rely on evaporation to reduce the volume of water as new sewage flows in. Enclosed home sewage systems are also used for local treatment, but these underground systems are different and usually require pumping if they lack a drain field. Commercial wastewater designs usually combine both covered and open tanks and ponds to handle various stages of gas generation and purification. Exposure to sunlight and air flow is beneficial in some applications and unwanted during other stages. Durable covers are as important as the liners, especially when hazardous or explosive gases are generated during waste processing.
Complexity of Treatment Equipment
Backyard and neighborhood lagoons rarely need more than a small air pump or overflow drain to properly process daily volumes of waste. Unless there’s flooding conditions or damage to the pond, there’s little need for other complex types of treatment equipment. In contrast, even a small-scale commercial sewage lagoon can integrate half a dozen different pieces of equipment. From sewage pumps to aerators, filters, UV lights, and osmosis membranes, there’s plenty of options for turning wastewater into cleaner liquids. Plan for the space needed around the edges of ponds using this equipment so there’s no overcrowding or blocking of pathways for maintenance and repairs.
Residential and commercial sewage lagoons share similar safety risks since they both contain wastewater that could pose a health hazard. However, residential lagoons are more accessible to animals and humans curious about the water source. Commercial wastewater plants feature deeper ponds with more hazardous chemical mixtures, but they’re usually better secured and patrolled as well. Both types of lagoons need fencing and locked gates to keep everyone, animal or human, away from the water.
All sewage lagoons, regardless of size, need the same kinds of reliable liners. You can find what you need for wastewater ponds here at BTL Liners. Our products, such as ArmorPro and AquaArmor, are exceptional at handling the challenging conditions of long-term storage and treatment.