National Pollutant Discharge Elimination Systems (NPDES) Overview

A discharging sewage treatment systems treats and then discharges treated effluent to a stream, ditch or other surface water body.  An National Pollutant Discharge Elimination Systems (NPDES) permit must be obtained from the Ohio Environmental Protection Agency (Ohio EPA) Division of Surface Water whenever there is a discharge of treated or partially treated water to a surface water of the State. NPDES permits exist to regulate wastewater discharges by placing limitations on the quantity of pollutants that may be discharged and to establish monitoring requirements and other conditions. Federal regulations, Ohio water quality standards and NPDES permits were written to protect public health and the aquatic environment.

NPDES General Permit for Household Sewage Treatment Systems

Starting January 1, 2017 the Ohio EPA established only one general NPDES permit for household sewage treatment systems (HSTS) that provide statewide coverage to authorize the discharge of approved sewage treatment systems from households.  From January 1, 2007 to January 1, 2017 there were two general permits but since the inception of the new statewide sewage treatment rule implementation on January 1, 2015, there was no longer a need for two permits.

A homeowner that installs a replacement discharging sewage treatment system, and in limited cases a new discharge on an existing lot, must register for coverage under the general permit by submitting a notice of intent to Ohio EPA along with a registration fee.  Certain conditions must be met for the property and discharge to qualify to legally receive NPDES permit coverage. These conditions are found under the "Limitations of Coverage" section of the permit.

Read the instructions then fill out and download and print the current Notice of Intent form from Ohio EPA. 

In 2010 the Ohio EPA initiated the process of renewing that HSTS General Permit and as part of the process, the Ohio EPA requested field sampling data as required by the permit and maintained by at local health districts as part of the operation and maintenance of the system. This data provides a basis to evaluate how the various HSTS were performing in the field, and to evaluate the performance of the local health districts to manage the program, and to obtain and maintain sample results from permitted discharging systems.  The summary of this data and report may be accessed in the following link at 2010 NPDES Sampling Report.

Evaluating Projects for New Home Construction

This map from the Ohio EPA is used to evaluate properties to help identify Streams with Drainage Areas Greater than 5 Square Miles to be used to Evaluate Projects for New Home Construction.

Approved Systems

The NPDES general permit for HSTS contains water quality standards that discharging sewage treatment systems must meet. Manufacturers of HSTS that seek recommendation for approval of pretreatment components and treatment trains for NPDES general permit discharge through the Ohio Sewage Treatment System Technical Advisory Committee (TAC) must submit applications and supporting documentation. If all the proper effluent limit criteria is met, the TAC will recommend approval of the system to the director of the Ohio Department of Health (ODH). Once a manufacturer and system are approved by ODH, the system information including schematics, installation and inspection checklists, and operation and maintenance manuals will be posted on this website within the "Approved Sewage Products" page.

Fact Sheets 

Homeowner Fact Sheet for NPDES Systems
Sample Port Journal Entry for NPDES Systems
Homeowner Fact Sheet  on NPDES Systems that can be updated
Procedures for collection and testing effluent sampling
NPDES Sampling Action Level Chart