General Permit #4

Discharge from Private Sewage Disposal (Onsite) Wastewater Treatment and Systems

Any private sewage disposal wastewater treatment system (also known as an onsite system) that discharges treated wastewater to a designated water of the state or a subsurface drain tile must be monitored to ensure that it meets secondary treatment standards. To achieve these standards, all surface-discharging systems must obtain coverage under NPDES General Permit #4 and must meet all the monitoring requirements of the permit. A Notice of Intent (NOI) form must be filed with the NPDES Section of the Iowa DNR prior to the installation of the discharging onsite system. The NOI form may be obtained from a county sanitarian or downloaded below. The completed NOI must be sent to the Iowa DNR at the address noted on the form. Once the form is received, the Iowa DNR will issue a General Permit #4 to the system owner. There is no fee associated with permit coverage.

542-1541 NPDES General Permit #4: Notice of Intent (NOI)
542-1541 NPDES General Permit #4: Notice of Intent (NOI)

NPDES General Permit #4: General Information and Conditions

The treatment system owner is required by General Permit #4 to maintain records of operation and sample the discharge from the onsite wastewater system. These requirements are in addition to any county construction or operating permit requirements for the system. The owner is required to make arrangements for the test samples from the system to be analyzed by a certified laboratory. To find a certified laboratory, please use the State Hygienic Laboratory certified laboratories search.

Direct questions or comments regarding General Permit #4 to Tim Grotheer at or 515-452-7646.

Renewal of NPDES General Permit #4 for Private Sewage Disposal Systems

The DNR is proposing to renew General Permit #4. For more information on the rulemaking and to view the proposed general permit, please see the NPDES Rules page.