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Roles and responsibilities: On-site wastewater design professionals

General areas of responsibility

A practicing on-site wastewater design professional:

  • Performs services for new construction of a system.
  • Evaluates existing on-site disposal systems.
Subjects typically addressed by on-site wastewater design professionals
The following examples are general guidelines, and shouldn't be considered all inclusive.
Design area Subjects addressed by on-site wastewater design professionals
Site evaluation
  • Existing site and system conditions
  • Potable water source and utilities
  • Topography and property information
  • Surface water, ground water, and drainage
Evaluation of soil
  • Soil logs, sampling, and classifications
  • Impervious layers and seasonal water table
  • Fill areas and other adverse soil conditions
  • Type of disposal system
  • System components and operational parameters
Construction management
  • Disposal site preparation
  • Construction conformance with design
  • Report construction and site variances
  • Operational testing and owner use


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