Alternative Septic Systems.
In areas where the water table might be too close to the surface, or where the soil isn’t conducive to proper drainage, homeowners may consider a mound type of septic system. A mound type in a sense takes all the action that we would attribute to the drain field portion of a traditional septic system, and moves it up above the level of the water table, or non-optimal soils. Examples of soils that can cause problems for traditional septic systems include those that are either impermeable, or too permeable, or if there’s a very shallow layer over porous bedrock.
Mound systems consist of a dosing tank (which meters how much and how often the effluent reaches the mound) and the mound itself, which is made up of different layers of sand, gravel and soil. With this system, the effluent can be treated to the point where then the soil layers below can do the rest of the job, without any negative impact on the environment.
Another alternative type of septic system is an aerobic system. This type of system introduces oxygen, so oxygen-loving, or aerobic bacteria and grow and flourish. Bacteria that love oxygen can process waste faster, and more efficiently, and they can be installed above or below ground. Aerobic systems are a good option if you don’t want to or can’t clear enough land to support a traditional septic system, but they are more costly to build and maintain. The oxygen injection system requires electricity and equipment, but with proper maintenance they can be a great upgrade to a traditional anaerobic system.
Lagoons and Cesspools.
The kind of lagoon we’re talking about here isn’t the kind you’d want to swim in, and the kind of cesspool we’re talking about has nothing to do with politics!
A lagoon is simply an open-air, above ground aerobic drain field, and a cesspool is just an outdated way of slowing things down and storing waste until you could figure out what else you wanted to do with it (hence, why they are not being built anymore).
In areas where the ground is impermeable, or on large acreages, lagoons have been the way to go but as our society becomes more complex and people start living closer and closer together, it will be fairly uncommon to see new lagoons built, if at all.
Cesspools are generally unsafe and ineffective, so unless they are “grandfathered” in, you won’t see them being built, almost anywhere anymore.
Chamber systems, or gravelless chamber systems are an upgrade to the traditional septic system drain field. They are useful in areas where gravel isn’t readily available, is of poor quality, or in places where it would be too costly or cumbersome to transport it in. Gravelless chamber systems replace the gravel or rock usually associated with traditional drain fields with other materials (often recyclable) such as fabric or polystyrene, and also work well in areas where the water table is high, or where space may be a limiting factor.
Gravelless Chamber systems have been around for a while now, but they are becoming the go-to standard upgrade or replacement for either systems that have failed, or new construction. There are many different variations and options with chamber systems, so make sure you consult with a contractor who’s experienced with this type of excavation and installation.
Recirculating Sand Systems.
Yet another option you may want to consider is the recirculating sand system. The recirculating sand system works by distributing the effluent across a bed of sand, collecting the run-off, and then repeating the cycle until the clean water is discharged. These are a rather complicated and expensive alternative to maintain, but a good option if you have a high water table, or you are close to a body of water (rivers, lakes, oceans, etc).
As fun to say as they are to spell, evapotranspiration systems differ from the other systems mentioned in one important way: the effluent will never reach the ground, and it will never hit the groundwater. In effect, the evapotranspiration system is watertight, and the effluent evaporates into the air as opposed to being treated by microbial processes in the soil. This system works well in hot, arid climates, but will require more maintenance, permitting, and real estate to operate.
Drip Distribution Systems.
Drip distribution systems work great in areas where a mound system would be required, but without the mound being needed. The drawbacks of this type of system includes the complexity, real estate, and the dosing system needed to make sure that the drip system can work optimally.
Cluster or Community System.
Not all subdivisions are within city limits! In fact rural planned communities are growing in popularity! If you are interested in building in a subdivision that isn’t connected to city water, a cluster or community system may be a good option to be aware of. Each rural subdivision home will have their own septic tank, but share a common drain field and or dosing tank, that can be comprised of a traditional gravel system, drip distribution, chamber, or some other option.
Constructed Wetland System.
A final exotic option to explore is the constructed wetland system, which pays homage to the original water treatment system; nature. Constructed wetland systems mimic natural wetland systems by creating a basin in which microbes, plants and other organic media go to work and break down and treat the effluent. These systems can function either as a pressurized system, or gravity flow, and the next step of treatment can go beyond the wetland, or take place in the drain field.