Illinois Administrative Code
Title 35 - ENVIRONMENTAL PROTECTION
Part 370 - ILLINOIS RECOMMENDED STANDARDS FOR SEWAGE WORKS
Subpart C - DESIGN OF SEWERS
Section 370.300 - General Considerations
Current through Register Vol. 48, No. 38, September 20, 2024
a) Type of Sewers
The Agency will approve plans for new sewer systems and extensions only when designed as the separate sanitary type in which precipitation runoff and ground water from foundation drains are excluded. The Agency will not approve the installation of new combined sewers, except as provided in 35 Ill. Adm. Code 306.302.
b) Design Period
Sewer systems should be designed for the estimated ultimate tributary population, except in considering parts of the systems that can be readily increased in capacity. Similarly, consideration should be given to the maximum anticipated capacity of institutions, industrial parks, etc.
c) Design Factors
In determining the required capacities of sanitary sewers, the following factors should be considered: