Current through Register Vol. 48, No. 38, September 20, 2024
a) Each water and sewer utility may submit an
embedded cost-of-service study for each rate increase application based on costs for
the proposed test year. Each cost-of-service study submitted must include (at a
minimum) the information listed in subsections (b), (c) and (d). If a
cost-of-service study is not submitted, the utility must provide the necessary data
in subsections (b), (c) and (d) to enable Staff to perform a cost-of-service
study.
b) Schedule E-6: A full set of
cost-of-service results that presents the functionalization, classification and
allocation of all jurisdictional costs on the utility system. Present all
non-jurisdictional costs separately from jurisdictional costs in the study.
1) All costs broken down in detail to allow a full
cost-of-service study to be performed in accordance with the Uniform System of
Accounts (83 Ill. Adm. Code 605 and 650). The breakdown of expenses by Uniform
System of Accounts shall also include the following additional transmission and
distribution expenses: Mains, Meters, Services, Meter Installations, Hydrants, and
Distribution Reservoirs and Standpipes. Additionally, customer accounts expense
shall include meter reading in its breakdown of expenses.
2) A listing of all externally generated
allocation factors in the study.
3) A
full narrative description of the allocation methodology used in the cost-of-service
study that explains in detail:
A) The derivation
of all externally generated allocators; and
B) The basis for all direct assignments of costs
in the study.
c)
Work papers supporting Schedule E-6 shall include all materials relied on in
developing the cost-of-service study. This shall include, but not be limited to, the
following:
1) All work papers relied on to develop
the cost-of-service study in spreadsheet format, when applicable;
2) The following data on load factors used in the
cost-of-service study:
A) A listing of all load
factors used in the study by rate class and/or customer class; and
B) All studies and analyses relied on to develop
these load factors.
3) All
studies and/or analyses relied on by the utility to develop cost-of-service study
results.
4) The amount of plant in
service, contributions in aid of construction, and customer advances for:
A) Mains larger than eight inches in diameter;
and
B) Mains eight inches and smaller in
diameter.
d)
Customer usage structured as follows for the utility's rate groups:
1) For water utilities:
A) Number of customers by meter size for each
customer class; and
B) Water usage for
each customer class by rate block (1,000 gallon or 100 cubic foot).
2) For sewer utilities:
A) For flat rate customers, the number of billing
units by rate;
B) For customers billed
on water usage:
i) Number of customers by meter
size for each customer class; and
ii)
Water usage for each customer class by rate block (1,000 gallon or 100 cubic
foot).
