Management of Onsite Sewage Treatment Systems
By Ken Olson
The goal of on-site sewage treatment is to protect human health and the environment by safely recycling wastewater back into the natural environment in a cost-effective manner. Effective on-site treatment of wastewater is dependent on proper design, installation, operation and maintenance of the system. A well-designed system will not properly treat sewage over its intended life without appropriate operation and timely maintenance! Good management of an on-site system will improve the performance and extend the life of the system resulting in reduced total cost to the owner with increased reliability and satisfaction.
Management = Operation + Maintenance + Monitoring
One of the ‘hottest topics’ in on-site sewage treatment today is the management of systems! Once a well-designed system — including provisions for management - has been properly installed (the responsibility of the designer, installer and inspector) it must be used, watched and taken care of to meet its owner’s expectations. This is no different than any other piece of equipment we own.
"Standard" systems have been designed to require minimal management. Existing codes and rules have paid minimal attention to management and few if any enforcement agencies have provided significant encouragement for owners to follow good management practices. This lack of attention to good management has often proved costly to homeowners and the environment. We must now make a concerted effort to increase our attention to management of all systems — standard and ‘alternative’.
What is Operation?
‘Operation’ is the day-to-day use of the system by the residents. The ‘users’ of the system control the quality, quality and pattern of the wastewater entering the system. The performance of septic systems is greatly influenced by what enters it!
"Using" water does not mean it goes away forever but rather means that we are changing it from ‘clean water’ to ‘dirty water’ by adding human wastes, food particles, cleaners, soil, lint, and other materials. These additions contain pathogens, organic and inorganic solids, nutrients, and chemicals. We are counting on the system to clean it again for reuse later. Users determine the quantity of water used by the number of gallons per flush of the toilet, the length of showers, the number of loads of clothes washed, faucets running while brushing teeth or washing dishes, as well as the frequency of doing each of these things, and all other water use practices.
What is Maintenance?
‘Maintenance’ is the work of doing periodic upkeep on the system. It includes the repair, replacement, and cleaning of existing components. It can also be the addition of new components to enhance performance.
Examples of maintenance are: the repair of leaking fixtures and appliances, the replacement of septic tank baffles or weak pumps, the cleaning of effluent screens or lint filters, the removal of solids from a septic tank or composting toilet, or the addition of an effluent screen to the outlet baffle.
What is Monitoring?
The monitoring of a system is the frequent observation or testing of all on-site system components. It could even mean the testing of effluent or contents! An important aspect of monitoring is to know what needs to be watched, when it should be done and who’s going to do it — a plan! The results of monitoring should be recorded and the information used by those doing ‘operation’ and ‘maintenance’. The use of the information is what makes it valuable!
Examples of monitoring may include: knowing what goes down the drain; reading and recording the results of a flow meter; checking baffles, screens, pumps, and alarms for proper function; noting wet spots near the drainfield or mound; recording the date and condition of the septic tank when it is pumped; or sampling and testing effluent from a performance system and reporting the information to a local agency as required.
Management of "Alternative Treatment Systems"
Specific operation, maintenance and monitoring procedures should be planned and followed to provide good management of all systems. ‘Alternative’ treatment systems (i.e. sand/peat filters, constructed wetlands, aerobic tanks, composting units, etc.) typically involve special mechanical components, living plants, or other devises, which require special knowledge, skill and attention to perform as designed. Owners may wish to or be required to hire professional management of an ‘alternative’ system. The complexity and costs of management must be an important criteria considered in the initial selection of an ‘alternative’ system.
Who, When, How?
Total management of a system must involve the residents generating the sewage with varying levels of assistance from professionals. The individual owner will likely determine management responsibilities of a single household system. Traditional trench and mound systems requiring relatively simple management are typically managed by the owner using licensed pumpers and other professionals as needed. Homeowners are capable of handling typical management tasks if they are aware of what needs to be done and make a commitment to it. Owners of complex systems or those unwilling to make the commitment may feel the necessity or be required to hire outside professional management. More opportunities to ‘contract out’ some steps will likely be available in the future.
Multiple-household systems have another dimension to management — other users. Each homeowner is responsible for the content and quantity of the wastewater generated and must rely on co-users to do the same. All users collectively are responsible to each other and for the management of the commonly used portions of the system. Common components could include large ‘community’ septic tanks, pre-treatment units or the soil treatment/dispersal system (i.e. trench, mound, wetland, drip lines, etc.).
A good management plan will specify ‘who will do what’ and ‘when and how’ they will do it. Each system is unique. The plan must be for the specific system and must be followed to be effective! In some multi-household systems residents can do some management tasks, such as reading water meters, but most functions will require additional equipment, skill and commitment.
The amount and cost of management will vary considerably with the size, type, and complexity of the treatment system. Owners must be willing to pay for the necessary management to achieve effectiveness and efficiency of their investment.
The bottom line is that a responsible person or entity — resident, business or private/public organization, must be designated to know and carryout the specific management practices required for successful treatment of wastewater in any system including on-site systems. For individual or multi-household systems in Minnesota there are several management structure options to choose from:
- Environmental Subordinate Service Districts
- Sanitary Sewer Districts
- Home Owner Associations
- Municipal Utilities
- Homeowner Cooperatives
- Private Joint Ventures
Each option has strengths and weaknesses to be considered for any local application. These options will be discussed in detail in the August/September issue of Focus 10,000.
A properly designed, installed, operated, & maintained on-site system = safely recycled water!