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There are an estimated 800,000 residences and small businesses in Indiana which are not connected to a centralized sewage treatment facility.

The Indiana State Department of Health has stated that as many as 200,000 of these have an inadequate means of sewage disposal. This is a significant public health concern, especially for the 700 or so small unsewered communities in the state.

Many of these are older communities that never really planned for sewage disposal; in fact, several have direct discharges or connections to town drains due to a lack of such planning. They often cannot solve the problem using individual on-site systems due to small lots that are poorly suited for on-site systems. Such problems will continue until cost efficient technologies are made available to these communities.

Communities expanding into rural areas also need these new
technologies so that additional sewage disposalproblems are not created.

A centralized wastewater system is an excellent solution in larger densely populated areas, since the cost of a municipal sewage system is lower if it can be distributed over a larger number of users.

However, centralized treatment systems operated by small communities often perform poorly because the expertise and funding is not be available to update and maintain the facilities. In fact, sewered small communities which treat and discharge wastewater account for most noncompliance violations, according to the U.S. Environmental Protection Agency. It would seem, therefore, that non-discharging decentralized wastewater treatment systems, or “cluster systems,”
should be carefully considered for this type of community. In an April 1997 report to Congress on the Use of Decentralized Wastewater
Treatment Systems, the U.S. EPA stated that, “Adequately managed decentralized wastewater systems are a cost-effective and long-term option for meeting public health and water quality goals, particularly in less densely populated areas.”

This support of alternative on-site systems for small communities is a major shift from previous national policies.

Over the past 25 years the nation has made significant strides in addressing the wastewater treatment needs of communities across the country.

But enormous wastewater treatment needs remain — especially in small communities. EPA’s 1996 Clean Water Needs Survey estimated that small communities need an additional $13.8 billion to comply with the Clean Water Act by the year 2016. Nearly $8 billion in government
funding has already been provided to small communities for wastewater treatment projects since 1992.

Cluster systems transport wastewater via alternative sewers to either a conventional treatment plant or to a pretreatment facility followed by soil absorption of the effluent. Cluster systems can be environmentally sound, financially responsible solutions for small community wastewater problems, where conventional central treatment systems are not practical or affordable and where individual on-site systems are inappropriate because of site or soil limitations.

This publication will focus on alternatives to conventional large-diameter gravity sewers and on pretreatment and soil absorption, rather than
treatment/discharge systems. It will discuss the various components of a cluster system, their advantages and disadvantages, and anagement
needs to ensure their proper operation. The community and financial procedures necessary to plan, build, and maintain a cluster system will
also be covered.

Download Link:

Free Environmental Engineering Ebook: Small Community Wastewater Cluster Systems