MULTIPLE-FAMILY DEVELOPMENTS

Water Protection Program fact sheet
03/2014
Division of Environmental Quality Director: Leanne Tippett Mosby
PUB2155

This fact sheet outlines when a multiple family development is required to receive approval for the method of wastewater treatment and how it receives that approval per 10 CSR 20-6.030 Disposal of Wastewater in Residential Housing Developments. This is available on the Missouri Secretary of State’s website at www.sos.mo.gov/adrules/csr/current/10csr/10c20-6b.pdf.

This fact sheet is not intended to explain how a subdivision receives approval from the department for the method of wastewater treatment. A link to the departments fact sheet On-site Wastewater Disposal in a Subdivision - PUB2226, can be found at www.dnr.mo.gov/pubs/pub2226.htm.

For the purpose of this rule, each unit of a multiple family development (apartment, hotel room, RV campsite, etc.) is counted as a single family residence. Multiple family developments that discharge less than or equal to 3,000 gallons per day of domestic wastewater into a subsurface soil absorption systems are required to receive approval for the method of wastewater treatment if the development will have seven or more units or for development expansions of three or more units. At minimum, the department would require an engineer’s report as stated in Section (6) of the Residential Housing Rule. That report must follow the criteria set forth in 10 CSR 20-8.020 Design of Small Sewage Works.

If the flows are greater than 3,000 gallons per day for the subsurface soil absorption system or they discharge directly into the environment the developer should contact the department’s regional office for assistance and permitting. The location, phone number and address of the department’s regional offices are available at dnr.mo.gov/regions/regions.htm.

Engineer’s Report
The following is required as the minimum components of an engineer’s report. The department may require more information depending upon geology, soils, landscape position and the complexity of the site conditions that may influence its ability to treat and control the wastewater.

The soils report must contain a topographic map delineating the proposed dispersal areas into the following categories: 0-2 percent, 3-14 percent, 15-30 percent and 31 percent and greater. Along with a map delineating the depth of the acceptable soils into the following categories: less than 18 inches, 18 to 30 inches and greater than 30 inches over bedrock or a limiting layer.

Department Review
To ensure an efficient review and reduce delays, please submit all of the required documentation at one time. A copy of the Request for Approval under 10 CSR 20-6.030 Disposal of Wastewater in Residential Housing Developments form (MO 780-1706) can be found at dnr.mo.gov/forms/780-1706-f.pdf. The department does not charge a fee to review these submittals.

The developer must comply with all of the conditions written in the department’s approval letter as well as the Missouri Clean Water Law and its corresponding regulations. The developer must meet these requirements before the sale or lease or start of construction by any developer or other individual. There cannot be any deviation or change that may adversely affect the geohydrologic evaluation, soils, estimated daily flow or the reported water supply for the development without first securing written approval of the proposed changes from the department.

Approval for the method of wastewater disposal under 10 CSR 20-6.030 should not be considered as approval for the reported potable water supply. It also does not excuse the developer or any other individual from complying with or from liability for violations of the Missouri Clean Water Law and regulations or any other state or local laws.

After the method of wastewater treatment receives written approval, the developer must contact either the Department of Health and Senior Services or local administrative authority, which is commonly the local health department, to receive assistance and information regarding the necessary permits to construct. Approval from the department does not obligate the Department of Health and Senior Services or local administrative authority to approve any particular type of subsurface soil absorption system or that a wastewater system will be approved for the development.

Summary
Remember for the purpose of compliance with 10 CRS 20-6.030 each unit is considered equal to a single family residence. The components described above are required as the minimum for an engineer’s report, although more information may be required depending upon the complexity of the site and its ability to treat and control the wastewater.

The department realizes there is always an infinite number of “What if” questions this and other fact sheets may not be able to answer. If you have any questions concerning your specific project, please contact the department for assistance.

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