Storm Water

Elmhurst Weather and Flooding History:

1871 - weather records start to be maintained
Feb 1957 - 6.2 inches of rain - 86 plus year event - highest on record
Jan 1987 - RJN Consultant starts the studies and reports by actions of Mayor Quinn
8/14/1987 - 8-9 inches of rain - largest to date - 1.9 inches in short period record - 30 year event - Spring and Eggleston did NOT flood?
1987 - IL EPA Consent Decree #1
July 18, 1988 Cross connect grandfather start date for legal non-compliance with I/I and storm to swer cross connects. Not sure why?
9/12-14/2008 - Hurricane Ike remnants - 7.22 inches in Elmhurst - some got 8.45 inches in region - peaked 1.01 inches in a short period - 21 year event
2/26/2009 - 20:51 - .83 inches in a very short period
7/23-24/2010 - 7.35 inches in 8 hrs - highest record per rain rate per hour event - - 1.99 inches in short period breaking rate record - less than 2 years since last major!
Oct 7, 2010 - Mayor DiCianni started the Stormwater Task Force
June 12, 2011 - Jim Grabowski shows on Patch as accepted the City Manager position.
July 19, 2011 - Complaint filed against Elmhurst IL EPA files suit against Elmhurst for Sewer and storm problems polluting Salt Creek 6 counts for violating Section12(a),(d),(f) of 415 ILCS 5/12 (2010) - negotiations start - COE filed response Dec 29, 2011.
3/2013 - City Council election - LOWV Storm question arises from Christopher Burke Storm study
4/18/2013 - 7.0+ inches over 18 hours - Youtube - 1.03 inches in less than 1 hour
Sept 15, 2014 COE full council approves Consent decree on R-70-2014 - Mayor Morley signed for COE
Sept 17, 2014 - Consent Decree #2 is finalized after 3 years 2 months - Sanitary Sewer Evaluation Survey and then Study
Dec/2014 - Consent Decree #2 - Sanitary Improvement Plan
Feb 2, 2015 - Modification of Consent Decree #2
6/15/2015 - above the street flooding - 2.56 inches ORD (24hrs)
Jan 6, 2016 - Modification #2 of consnent decree #2
10/14/2017 - 7.6 inches in 24 hours - 7 years since last major
5/30/2018 - 2.5 inches in under 2 hours breaking the rate record of 7/23/2010 of 0.91875 inches per hour.
2018 - $30.6M in 11/9? storm water projects protecting 353 homes $86,686/home avg
5/17/2020 - 3.1 inches Sunday night and 7.9 inches total - 2 years since last major event
6/1/2023 - .88 inches in less than 1 hour - could have broken the rate record?
7/1/2023 - 7/2/23 - first 12 hours 4.0 inches - no visible impact to southern storm retention projects.

March 2013 - Alderman Chris (Ward 5) Healy on Storm water:

Consultants suggest most of the city’s flooding and sewer problems require fixes at individual residences. Homeowners may resist, especially if there is a cost. How do you propose getting that done?

I am on the Public Works and Buildings Committee of the City Council that is addressing some of those very issues right now. The first steps, which are almost completed, are scoping the problems and identifying the possible solutions. The next steps will be to prioritize the solutions and start to figure out how to fund those solutions. We need to make sure we spend our money wisely and make sure the money we do spend improves the ability of the largest numbers of homes to handle another major storm event. Public education will be vitally important to make sure the residents understand what the problems are, how their specific home may be contributing to the problem and what possible city programs (like 50/50 cost share programs) might be available to help them make these changes. It will also be very important to educate the public on what we are doing and the level of added protection it affords us, however no amount of flood protection/proofing will ever be enough to stop Mother Nature and her next huge storm. We need to make sure we clearly communicate that there is no such thing as 100 percent flood protection.

Rex's Arm chair quarterback: Failed to mention price/Home mitigation cost - drove right around that key component of the question posed. Also storm water was his third published priority after economic development and improving the electrical grid.

Marti Deuter - same question:

City Council recently moved forward on improvements to the sanitary system in southwest Elmhurst. While this is an important first step, public infrastructure improvements will address only a portion of the flooding and sewer issues. The studies conducted have shown that the greatest contributor to the problem is the amount of clean water entering the system from private residences during and after a storm. Resident awareness and education about the problem and its causes must be a priority. All residents should receive communication that clearly describes the findings of the consulting engineers and resident task forces. The city should also help homeowners identify the most cost effective improvements to private residences and continue, and possibly expand, existing cost-sharing programs. Addressing the private side of this issue will not be a simple task. But without changes to private residences, the effectiveness of any investments in public infrastructure will be limited.

Residential Stormwater Management Incentive Program (October 2014).pdf

2014 - October 14 - Residential Stormwater Management Incentive Program

Full council approved 10/20/14 - Annually funded at $50,000 (~80 homes capacity over 8 years)

This puts value to a CF of onsite water storage from $8.50 - $22

1 cubic foot holds 7.48 gallons.

Also alludes strongly that new homes and their direct connected downspouts to storm system weighs more heavily that legacy homes with over the ground roof gutters exit strategies?

2/27/2017 - Public Works Director Killian presented the agenda item and gave a brief update on the various stormwater construction projects that are currently on-going. He also presented the funding status of the current and future stormwater projects as they relate to the 2015 and 2016 bond issuances. Killian stated that, as of right now, it appears the current (W/M/E, Crescent/Cambridge, Harrison, York/I-290, Madison, & Geneva) and future (Washington, Pine/Avon, and SESMP-Phase I) projects should be covered by the 2015 ($4,200,000) and 2016 ($25,400,000) bond issuances. Any other future stormwater improvements would need to be assessed for other possible funding sources.

SESMP-Phase 2 must have put it over the capacity of our ability to pay for the debt incurred?

Finance committee 3/14/22 - Other Business

Chair Dunn explained the City’s need for additional revenue within the Stormwater Fund to cover existing debt. He stated that in previous Committee discussions possible solutions included home rule sales tax, a property tax levy, non-abatement of the stormwater debt on the property tax levy, and a stormwater fee. The Committee asked staff to aggregate prior information, the ongoing and future stormwater projects, and a breakdown of required cash flow.

R-86-2022.pdf

9/6/22 - Approval to engage Consultant for Stormwater Fee Study Project

Phase 1 (historical) - $41,165

Phase 2 (TBD) ~$74,000

citizen outreach and education, etc.
Billing system updates, etc
Implementation

Elmhurst Stormwater Feasability Committee Update.pdf

elmhurst_sw_feasibility_may_22_committee_mtg_v2.pdf

Consultant Stantec - Stormwater Fee Study Project

presented in committee Mon 3/13/23 (v1 study),

5/8/23, and

5/22/23 (v2 study)

Discussed with following points:

Pay as you Go or Bond Debt
Tiered or all pay the same
Property taxes or Storm fee on water bill - or a Hybrid
Residential versus Commercial share of storm water mitigation
Home Rule Sales tax put on table - card down.

Last Outcome:

No action taken, further tuning back to consultant and city staff - might be a 8 week cycle - TBD by committee chair. Potentially July 10 or July 24- TBD

Open questions:

Structural / Study Clarifications:

Parking lot (sqft) allocation not fully included in non residential calculations when they are detached parking lot parcels and should be fully pushed over to the commercial allocation.
Pie chart on page 17/37 appears off $22,500 from a total of 4.5M total of the pie?
Lets put a model together of the "bonding" for the future $35.2M storm capital budget as is and a reduced item version of $"x" M annual and make a pie chart for final res/com (R/C) loads showing color for fee, sales tax, and any property tax with in each (R/C) sector.
What is the "Public" classification with 59 parcels?
Why is the median (3,400 sqft) and the average residential (3,301sqft) leaving a delta of 99 or 2.9% - appears due to large long tail to the right side with large lots and very low parcel counts in each column?
"Duplex or Townhouse" has an average impervious sqft per unit of 731 that appears to low?
What about past 10 years - what is that strategy - asked and TBD?

Equity Considerations:

Residential property choices might need refinement to make a better sell to the Elmhurst homeowners. Tier 1 model should be a rear detached garage with the driveway excluded and thus will have a much lower ERU ratio than 0.65 and likely 1,300/7,500 = .17 - With a driveway 120 x 10 that still lands at 2,300/7,500 = 0.31
Tier 1 parcel count of only 1,651 should be expanded greatly to a number near 50% of original homes built and this will bring Tier 2 down by 2,500-3,000 parcels. Homes that are below EAV of $127,480 and have a retired person making less than 65,000 should be materially exempt from Storm as they have subsidized water rates for 2 decades.
Fixed rate of $0.0042/sqft could be considered regressive, recommend that be stepped increased by Tiers in the modeling.
Last study model has Residential load at 75.3% with both water bill "Storm Fee" and property tax load ($1.3M * 85%) when their impervious load is 53%

Alternatives to Fund Storm water Remediation

Impact fees or "another name" on ALL new construction - $1,875,000 on 100 Res parcels and MHU/unit at $45,000 and $30,000 respectively at closing time. This is cheaper than the current historical capital cost $105,000 per home remediated?
Charging a fair CIRC "Storm fee" on MHU tenants on their water bill could provide an $1,663,400 annually to the Storm fund at only $7.54 per 2 month billing.
Sales Use Tax 25% incremental that injects $1,950,000 annually
Carefully review and find less costly alternatives $/home - the CEB Storms 10 year capital budget of $30,220,500 and after escalation at $35,200,000 as this impacts the 3.5 - 4.5M annual current requirement.
Property tax load of $1.30M annually (carry over from the completed Library construction bond debt) with a residential ratio of 85% comes to $1,105,000 divided by 15,000 meters comes to $12.30 /per water bill or $6.14/monthly. Less than 30% of Elmhurst homeowners have enough property tax and interest on their mortgage to exceed the standard married filing joint deduction of $25,900 so the tax shielding argument has merit in separate Tiered rate structure. Total property tax shielding for a storm water property tax incremental (MTR of 24%) for this "sub 30%" is estimated at $2,048,000 annually or $478/HH or $39.86 monthly.

Elmhurst Storm Water Rate v5.xlsx

My rebuild and verification of the consultants model

Parking lot allocation is now in the Stantec model but with above caveats

What is an acre foot of water and how much of that is considered a 100 year storm and how much storage is needed for a 50 x 150 parcel to hold a 100 year storm event?

acre foot of water is 43,560 cubic feet (1,233.5 m3) of space. If it were water then that is an equivalent of 325,853 U.S. gallons

100 year storm - 24-hour period used to be 7.58 inches, but now in Chicago it is 8.57 inches.

This is 8.57" / 12" = 71.42% of the 325,853 gallons or 232,713 gallons per acre

50 x 150 parcel is 7,500 square feet or 5.81% of 1 acre. Thus 100 year flood would be 5.81% of 232,713 or 13,521 gallons. The good news is some of that water successfully flows to Salt Creek before flooding occurs. If it were:

3 inches before flooding ensued then we would need 8,788 gallons of storage - 2014 price = $9,986 - $25,847

4 inches before flooding ensued then we would need 7,210 gallons of storage

5 inches before flooding ensued then we would need 5,632 gallons of storage

4/6/22 Package from Dir Coyle - very informative

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