Most states in the US publish design flow charts to stipulate the capacity of wastewater systems. Here’s a list of residential and commercial design flow charts for new construction organized by state.
These documents have been downloaded from various regulatory agencies. Jurisdictions for any particular job will vary. Aqua Tech makes no certifications regarding the veracity, applicability, or relevance of the documents listed below.
Contact us for more on how to plan the wastewater component of your particular project:
One of the biggest challenges to implementing comprehensive land use plans is how to accommodate new development in locally designated growth areas that do not have public sewers. Many rural and suburbanized towns in the US face this question.
They want to direct growth to the most suitable areas of town – near existing services, such as fire stations and schools, for example – but have no prospect of gaining access to public sewer lines. New development must rely on soils, usually on a lot by lot basis, to handle wastewater. The conventional wisdom says that means low densities of development, negating the effectiveness of a growth area. However, towns and counties without public sewer systems have options that they may not realize.
Additionally, watersheds in the United States reflect tremendous diversity of climatic conditions, geology, soils, and other factors that influence water flow, flora and fauna. There is equally great variation in historical experience, cultural expression, institutional arrangements, laws, policies and attitudes. With regards to wastewater issues, it would be a mistake to impose a standard model from the federal level to address the needs on a local level. Correspondingly, centralized sewer systems are aging, frequently underfunded with respect to replacement costs and expensive to maintain. In addition, centralized sewer strategies are increasingly challenged by environmental and social considerations such as inter-basin transfer issues, aquifer depletion, nutrient loading and urban sprawl.
The new emerging civic agenda of smart growth, community preservation, open space planning, ecologically sound economic development, resource conservation, and watershed management demands that we rethink what constitutes assets and liabilities. With a capacity of roughly 200,000 gallons per day, these off-grid plants can be constructed at a cost of well under $3,000 per home. These are economic, environmental and quality of life issues and they do not lend themselves to single purpose solutions. They require local community based consideration within the context of flexible multipurpose planning.
Statistics have shown us that within the U.S., twenty-five percent of existing residential real estate and forty-seven percent of new construction are served by onsite treatment systems. Many of these systems are acknowledged to be inadequate with respect to soil absorption, nutrient removal, resource protection and public health. Ironically, despite these statistics and EPA policy changes, most regulatory codes as well as most municipal and commercial planning continue to consider onsite systems to be temporary solutions awaiting a centralized sewer hookup.
Looking beyond the traditional assumption that wastewater is simply a matter of safe disposal and the public health; the real contemporary wastewater issues are the economic and environmental issues in which the public has a primary interest:
Drinking water quality
Deterioration of recreational water resources and other natural systems services
Economic development in small and rural communities
Beyond just disposal, decentralized wastewater management has the potential to contribute to the formation of an infrastructure to sustain watershed integrity. Decentralized wastewater treatment serves the “watershed agenda” and the principles of “community preservation” and “sustainable development.”
When approaches to the larger wastewater issues are successfully accomplished everyone benefits:
Local communities win open space zoning, water quality and supply protection, increased development capacity and an expanding tax base.
Natural systems are sustained through prudent zoning and reduction of non-point pollution.
Developers win additional lots for development and higher margins typically associated with conservation subdivision design and municipal infrastructure.
Regulatory agencies win because they gain partners in compliance management such as the municipality and perhaps a watershed authority.
Citizens and homeowners win because property values are enhanced as schools, healthcare providers, and retail outlets crop up around the new infrastructure which decentralized systems provide.
There are no major obstacles to a decentralized infrastructure for wastewater treatment.
New technologies in a properly managed context provide the opportunity for a land based watershed initiative that could significantly reduce small flow point source discharges such as those associated with onsite treatment systems. A decentralized wastewater management infrastructure should include:
Clustered, performance-based, decentralized wastewater management systems
Industrial & commercial pretreatment prior to discharge to existing sewage treatment systems
Wastewater reuse systems
Estimates suggest that this infrastructure is achievable with technologies that require 50% to 70% less space with corresponding reductions in cost of 40% to 50%. For citizens in small and rural communities these reductions represent opportunities to preserve water quality, to stimulate economic development and job formation and to restore property values. Essentially, we are shifting from large sewage collection systems and centralized treatment plants to small and decentralized management systems. Keep in mind also that this is not an alternative to centralized sewer. Rather, it is a complimentary adjunct to the existing infrastructure.
Moreover, the decentralized solution is coming from local community and watershed needs. It is not coming from the bureaucracy. It is essentially good old bottom-up American pragmatism. It is important, therefore, that the general population becomes informed about the benefits of the decentralized approach. We must find a suitable mechanism to accelerate the progress to support watershed management. If we can not find such a mechanism, we run the risk of letting the limited existing strategies (centralized and onsite) dominate the next 20 to 30 year cycle.
These collection or conveyance systems often represent the major portion of the total capital cost associated with any wastewater system, so careful consideration should be made to avoid extraneous expense while also ensuring reliability and environmental compliance.
Let us help you design a system that takes everything into account.
Our STEP system creates a pressurized, small pipe influent delivery structure to the treatment plant which eliminates the need for the expensive piping and lift stations that gravity systems require. This means that developers can cut their cost as well as defer some of that reduced cost of the community wastewater system until lots are sold. Since each home shoulders some of the load associated with wastewater treatment, the initial cost and maintenance can be distributed to the homeowners as well.
Beyond reducing development cost, STEP technology further enhances effluent water quality by leaving the majority of the solids at the point of origin where they can degrade through anaerobic processes. The effluent leaving the tank at the home then becomes the influent which the next component in the Aqua Tech system will treat through aerobic processes.