Septic Factsheet Series

Tips and Reference Guides for Homeowners

Aerobic Treatment Units Explained: Some of the limited conditions include soil saturation, diverse types of soil, elevation of groundwater and proximity to waterways. Due to these conditions, aerobic treatment or mechanical units are more prevalent for installation. Aerobic treatment units (ATUs) will have similar configurations with a pumping station and chlorine contact chamber before discharge but will operate slightly differently than a conventional system.

Conventional Septic Systems Explained: To reduce the cost of collecting, processing and treating wastewater in some areas, the use of individual septic units or on-site wastewater treatment systems is a method of treating wastewater from household plumbing fixtures (toilet, shower, laundry, etc.) through more natural processes. Also known as decentralized wastewater treatment, these underground units use primary and secondary treatment to treat and disperse small volumes of effluent generated in residential settings.

What Types of Wastewater Do You Generate: One of the largest factors for maintaining proper treatment of a decentralized septic system is the water volume that is flushed through the primary tank. The wastewater effluent is generated by a number of appliances including toilets, showers, sinks, dishwashers and washing machines. Wastewater can be classified as either “gray water” or “black water.”

Effluent Reduction Guidelines: Alternative Treatment and Dispersion Techniques: When conventional absorption fields cannot be used, there are alternative methods for secondary treatment and distribution of effluent that can be utilized. The methods may vary based on parish but will mostly be due to local topography, available space, soil profile and water table elevation. Specific guidelines for alternative treatment and dispersion techniques regulations can be found…

Sanitation Guide for Limited-Use Septic Systems: Geographically, Louisiana’s coastal landscape provides ample opportunities for hunting, fishing, tourism and commercial industries. Though the impact of storms in recent years has dwindled coastal infrastructure and populations, many semipermanent camps or properties host activities throughout the year. A unique aspect of these locations is the wetland or marsh-based soil that lacks a foundation for permanent water infrastructure.

Navigating Floods and Power Outages for Septic Systems: Louisiana has a history of impactful weather events which have negative consequences on infrastructure. Before hurricane season, take stock in preventative maintenance tips and get a checklist ready to get your septic system back online to reduce downstream water quality issues. A key to a healthy, efficient septic unit is a well-maintained system.

Preventative Maintenance Tips and Warning Signs of Septic Issues for Homeowners: Maintenance is key to the efficient performance of any sewage system. By emphasizing proper maintenance and the knowledge to recognize when issues may arise, you can reduce the risk of public health hazards and environmental contamination. To do this, homeowners should understand how the septic configuration operates and where problems can occur in the process.

Study Materials for Onsite Wastewater Installers Workshop

Definitions: The following definitions and permit specifications are outlined for the Onsite Wastewater Installers Workshop and come directly from the Public Health Sanitary Code LAC Title 51 Part XIII. This document is meant to be a study guide for installers to become familiar with the terminology outlined by the office of public health.

Conventional Septic Tanks: A septic tank is a watertight tank made of steel concrete, or other approved materials in which the settleable solids settle and are largely changed into liquids or gases by bacterial decomposition. The remaining residue in the tank is a heavy, black semiliquid sludge that must be removed from the tank periodically by a commercial contractor.

Absorption Trenches: A conventional septic system is a primary treatment technique that uses an absorption trench for the secondary treatment of effluent. These trenches can be used where soil conditions are satisfactory, sufficient land space is owned, and it will not cause an issue to public health. The effluent seeps through the aggregate-filled trenches and uses the microbial activity in the soil to convert organic matter from septic tanks into mineral components.

Oxidation Ponds: An oxidation pond is a shallow pond designed to treat sewage by the influence of air and sunlight. This pond will serve as a secondary treatment technique and must be preceded by a septic tank for primary treatment. The septic tank feeds partially treated effluent to the oxidation pond, which uses a prolonged retention time for biological interactions of microbial bacteria, air, and sunlight to complete the digestion of harmful substances in the effluent.

Sand Filters: A deep-type sand filter bed is another alternative for the secondary treatment of septic tank effluent. The sand filter bed should remain aerobic throughout the treatment process. For aesthetic purposes, the cover of clean, washed, coarse gravel, not to exceed 6 inches in depth over the bed, is permitted. This form of secondary treatment can provide a high level of reduction for effluent nutrients. They are good alternatives for sites with high water tables or that are close to water bodies.

Pit Privy and Limited Use: Non-waterborne systems are allowed where a dwelling is not served with water under pressure, thus not allowing for a standard septic system. In these cases, non-waterborne systems are required for excreting disposal but are highly regulated due to the potential risk to public health.

Pumping Stations: The use of a pumping station is required when the topography or elevation of the site prevents gravity flow of liquid from one location to another. The pumping station can be a part of any orientation septic unit series including conventional septic/ absorption field systems, aerobic treatment units and other configurations using effluent reduction or distribution methods.

Chlorinators: Where effluent discharges are required to be chlorinated, a chlorine contact chamber should be used to disinfect the wastewater before distribution. Calcium hypochlorite, labeled for wastewater disinfection, shall be added in sufficient concentrations to maintain a minimum residual of 0.5 ppm total chlorine in the effluent. To achieve the required contact time for chlorine, a baffled chlorine contact chamber shall be used with recommended gallons per day (GPD) capacities

Effluent Reduction: An effluent reduction field is designed as a soil absorption field that will both treat and reduce the amount of effluent that drains from a septic system to the surrounding water courses. Individual sewage systems, with a capacity up to and including 1,500 gallons per day (GPD), that produce a treated off-site effluent shall include an effluent reducer as part of the overall system.

Aerobic Treatment Systems: In Louisiana, many conventional septic systems are unsuitable due to environmental conditions such as high water table, soil saturation, contamination potential for surrounding waterways or topography. In these instances, aerobic treatment units are utilized to process wastewater effluent by creating oxygen to break down the organic matter in sewage and promote aerobic bacterial activity. These mechanical systems require regular maintenance to treat effluent efficiently.

Rock-Plant Filter Bed: A rock-plant filter bed is a type of effluent reduction system that can follow a mechanical plant of high effluent volume. The size of the effluent reduction system installed has to correspond with the recommended size of the sewerage system. These systems use plants and microbes to improve water quality and reduce the volume of water from domestic wastewater treatment.

Spray Irrigation: A spray irrigation system is a type of dispersion system that promotes evaporation and soil infiltration of the effluent. It is highly recommended that effluent from a mechanical septic system be chlorinated in a chlorine contact chamber prior to spray irrigation. This system uses an electric pump where a float switch activates the pump to force the effluent through piping to pop-up or elevated rotating-type sprinkler heads to distribute to the yard.

Alternative Methods of Effluent Reduction: There are additional methodologies of effluent reduction and dispersion that are not prevalent in the state due to lot size, topography or other constraints, but are listed as available options for homeowners and installers. All designs or questions about alternative methods of effluent reduction should submitted to the sanitarian parish manager with approval needed prior to installation.