TITLE:
Analysis of Inflow Solutions among Eleven Sewer Systems
AUTHORS:
Frederick Bloetscher
KEYWORDS:
Inflow, Sanitary Sewer, Overflow, Rainfall, Groundwater, Infiltration
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.9 No.9,
September
23,
2021
ABSTRACT: This paper was undertaken to compare eleven utilities where part or all
of the utility was tested for infiltration and inflow with the intention of determining
the value of data gathered from midnight investigations, comparing potential costs (in 2020
dollars), and
understanding whether statistical methods can be used to predict potential
problems on the system. Inflow and infiltration amounts can be identified on a
utility system without significant effort. Inflow correction is robust and easy to implement
(though often overlooked). After inflow is addressed, the results indicated
that a midnight investigation could quickly identify portions of the sewer
system in need of attention. Maps of leaky pipe sections can be identified, and
commonalities in the system may become apparent. Statistical methods were used
to identify high groundwater levels and lateral issues as critical issues on
these systems. The methods can be utilized at other utilities to help guide
them to addressing the critical issues first as opposed to focusing only on the
traditional pipe lining solutions that often ignore the lateral and inflow
issues that plague utility managers.