Hydraulic modelling of Chicago Area Waterways System (CAWS) to assess the impact of hydrologic separation on water levels and potential flooding during extreme rainfall events in Chicago, Illinois

An unsteady 1D hydraulic model (HEC—RAS) was implemented for the Chicago Area Waterways System (CAWS) for two configurations: i) current conditions, and i) physical separation with barriers. Hydrologic conditions were those for the 100-year storm event observed in September 2008. Combined Sewer Overflow hydrographs at +150 locations were estimated using the CityModel (InfoWorks). Historic conditions were defined by setting historic operation of gates and locks at controlling structures at Lakefront and Lockport. Also operation rules were set for required get open heights based on water levels at reference stations. Results show that the physical barriers and a new operation (lakefront structures permanently full-open) do have important consequences on the water levels in the CAWS. Control of water levels from Lockport would be lost on the lakeside of the barrier, and Lake Michigan would become a dominant factor on water levels. Although peak water levels would not necessarily increase in the presence of the barrier, water levels remain higher thereby increasing the chances that submerged outfalls would not be able to discharge stormwater, runoff, and CSOs into CAWS, and that flow back-ups would occur in sewers. Since the storage capacity of the CAWS on the lakeside of the barrier would be significatively reduced, reversals volumes to Lake Michigan would increase in the presence of the barrier.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Civil Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2014

Author dc:creator

• Santacruz Salazar, Santiago

Contributors dc:contributor

• Garcia, Marcelo H.

• Chicago River
• Hydrologic Engineering Centers River Analysis System (HEC-RAS)

Statement dc:rights

• Copyright 2014 Santiago Santacruz

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/49398

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/49398