Chapter 3.1
Development Patterns and Infill

• ALL
• Remove Code Barriers
• Create Incentives
• Fill Regulatory Gaps

Community Septic Systems

INTRODUCTION

Due to advancements in septic technology and the acknowledged shortcomings of conventional waste treatment systems, especially individual septic systems, decentralized waste treatment systems are becoming increasingly popular.[1] A community septic system, if built and run properly, can be a cost-effective, efficient, and effective waste treatment system that allows multiple users to connect to a shared septic tank or field thus allowing for smaller lot and clustered development that can preserve open space and wildlife habitat.[2]

The U.S. Environmental Protection Agency (EPA) notes that local governments either inadequately regulate or needlessly ban community septic systems.[3] To encourage utilization of community septic systems, local governments should consider eliminating bans and clearly define the appropriate regulating authority. This authority should oversee a rigorous inspection and enforcement program and require private owners to create a homeowner’s association or some other collective entity to pay for regular maintenance on the system.[4] Such authority should also eliminate any exemptions from groundwater standards before community septic systems will be approved.[5] To best protect human and environment health, local governments should require evidence of soil suitability and additional treatment near sensitive areas for approval.[6]

Local governments that permit and adequately regulate community septic systems can reliably protect human and environmental health, avoid costly centralized sewer infrastructure development, and decrease minimum lot sizes. To further promote adoption of community septic systems, local governments can collaborate with state authorities to create grant programs, or provide information regarding rebates, that will decrease costs for developers and homeowners.[7]

EFFECTS

Local governments that permit community septic systems can realize a variety of cost savings and environmental benefits if constructed and administered properly. [8] First, community septic systems can be a low-cost alternative to conventional centralized sewer systems because they require lower initial investment, offer easier installation, and require less expensive maintenance. [9] Additionally, community septic systems can be built quicker and reduce environmental impact because installation of sewage infrastructure across great distances is eliminated.[10] Since these systems treat wastewater passively and close to the source, operation can be more efficient which can result in substantial energy savings while also recharging local aquifers by not moving water offsite.[11] Furthermore, these systems allow developers to overcome design limitations, particularly in rural areas, by moving the septic system off individual lots and onto a shared space. [12] Such flexibility permits smaller lot sizes and the clustering of development that can encourage creation of conservation subdivisions that preserve open greenspace and wildlife habitat.[13] Finally, if oversight is rigorous and performed routinely by qualified experts, community septic systems may provide cheaper, safer, and more reliable waste treatment compared to other methods, especially individual septic systems.[14]

EXAMPLES

Middleton, WI

The City of Middleton seeks to protect wildlife by encouraging Conservation Subdivisions and discouraging urban development in rural zones.[15] When developing a Conservation Subdivision, the city permits community septic systems to reduce lot sizes and increase open space.[16] In Wisconsin, community septic systems are reviewed by the Wisconsin Department of Safety and Professional Services (DSPS) if the proposed project emits less than 12,000 gallons of waste per day, and jointly reviewed by the DSPS and State Department of Natural Resources if it contributes more than 12,000.[17] To facilitate the review process, the City provides an environmental checklist for developers to encourage efficient and orderly review.[18] One such proposed development was a conservation subdivision that included 103 lots on 162 acres.[19] Half of these lots were proposed to be connected to a joint community septic system of 16-20 lots. The utilization of a community septic system in such proposal would allow the clustering of residential properties that range in size from 5,000 to 20,000 square feet and set aside an estimated 81 acres for conservation.[20]

To view the provision, see Middleton, WI, Land Development Code § 19.01-.05 (2018).

See also Middleton, WI, Ordinance Review.

Mason County, WA

Mason County permits community septic systems for new developments outside of urban growth areas, for owners looking to replace existing septic systems, to serve isolated urban pockets, or to protect critical areas where conventional systems would be cost prohibitive.[21] The County differentiates procedures for approval based on whether the development is inside or outside of urban growth areas or within critical aquifer recharge areas. Regardless of location, operation and maintenance of any community septic system is required to conform to the standards and procedures set forth in the “Mason County On-Site Sewage Operation and Maintenance Program.”[22]

In areas outside of urban growth areas, where a development exceeds a density of one residential lot per acre, community septic systems are permitted provided it does not result in any localized affects that have a negative impact on wells or surface waters.[23] The County requires a site evaluation report to be provided by the developer. Approval of the site evaluation is contingent on a determination that there are no significant adverse impacts on local waterways.[24] In critical aquifer recharge areas, the County requires developers to acquire an environmental permit to operate.[25] To attain the permit a developer must implement best management practices pursuant to Washington State Department of Ecology and Health, Agriculture, Transportation, and State Conservation District Office standards.[26] To adequately administer and protect human and environmental health, the County maintains a database identifying all septic systems to establish inspection and monitoring procedures.[27]

To view the provision, see Mason County, WA, Code of Ordinances § 8.52.120 (2017); § 17.03.030 (2017).

Newton, CT

Newton, CT, pursues an aggressive sewer avoidance policy administered by the Water and Sewer Authority (WSA).[28] The WSA designates the boundaries to be served by existing sewer infrastructure and does not intend to extend existing coverage, instead choosing to control surface and groundwater pollution through zoning regulation and new wastewater systems.[29] In support of this policy community septic systems are permitted, specifically when creating open space conservation subdivisions (OSCS).[30] An example of such is The Riverview OSCS that was made possible by a community sewage system comprised of 49 two-bedroom houses that discharge 14,700 gallons of wastewater per day.[31]

The City encourages OSCS to provide areas of open greenspace and preservation of Newtown’s wildlife by leveraging their ability to cluster development.[32] Necessary for clustering is the ability to utilize community septic systems to decrease minimal lot sizes. The City permits community septic systems when in compliance with state, municipal, and specific ownership criteria.[33] For example, a community septic system must satisfy criteria found in the Sanitary Code and not exceed the lands ability to support proper waste disposal.[34] Such criteria regulates the rate of percolation, distance between leaching fields and ground water, location of ledge rock, and positioning of the system in relation to open waterways.[35] The City also requires testing and a professional survey to be conducted and submitted to the Zoning Enforcement Officer.[36] In addition to site requirements, an association of property owners who oversees the community septic system is required to be established. The HOA or similar association must have the authority and financial capacity to properly operate, maintain, and repair the community septic system, while raising and holding funds in escrow to ensure compliance.[37]

To view the provision, see Newton, CT, Code of Ordinances § 595-257 (2004).

ADDITIONAL EXAMPLES

Hamilton County, OH (adopting plan to modernize 20,000 decentralized wastewater systems that improve local wildlife and waterway health).

Lake Panorama, IA, Lake Panorama Building Codes Art. III (March 23, 2016) (creating the Lake Panorama Onsite Wastewater Management District to manage local wildlife and waterway health). See also Lake Panorama Fact Sheet.

EPA Open Space Development Model Ordinance (permitting shared septic systems).

ADDITIONAL RESOURCES

Decentralized Wastewater Treatment Can Be Green and Sustainable, EPA, https://perma.cc/92GZ-JNFX (last visited July 7, 2018).

Decentralized Wastewater Treatment Can Protect the Environment, Public Health, and Water Quality, EPA, https://perma.cc/958W-W5QV.

Decentralized Wastewater Treatment Can Be Cost Effective and Economical, EPA, https://perma.cc/GR6N-ANN5 (last visited July 7, 2018).

Voluntary National Guidelines for Management of Onsite and Clustered (Decentralized) Wastewater Treatment Systems, EPA (March 2003), https://perma.cc/6DYU-66M5 (last visited June 26, 2018).

Decentralized Wastewater Management Program Highlights, EPA (2013), https://perma.cc/W4N4-HW8J  (last visited June 27, 2018).

Maureen A. Tooke, Benefits of Decentralized Wastewater Treatment, EPA, https://perma.cc/5A2F-CR7L  (last visited June 27, 2018).

Lorraine Joubert et. al., Creative Community Design and Wastewater Management, National Decentralized Water Resources Capacity Development Project ix (March 2004), https://perma.cc/6BVP-2M42 (last visited June 27, 2018).

Sara Heger et. al., Community Septic System Owners Guide, University of Minnesota, https://perma.cc/WK92-5R76 (last visited June 27, 2018).