20 miles west of Chicago 327.5 square miles Over 900,000 residents Varying land use

42.2% residential

24.4 % open space

5.3% commercial

5.0% industrial

5.0% roadways and transportation

18.1 % other

West Branch DuPage River

126 square miles

East Branch DuPage River

81 square miles

Salt Creek

149 square miles

Listed as not supporting the aquatic life use

Chloride or TDS/conductivity

15 mile stretch of the West Branch DuPage River

8 mile stretch of the East Branch DuPage River

33 mile stretch of Salt Creek, including 7 miles of Addison Creek

State of Illinois 500 mg/L for General Use Water Quality

Standard

Listed in Section 302.208.g of Illinois Administrative Code

National Aquatic Life Criteria for chloride Parameter National Criteria

(mg/l) Chronic Acute

Chloride (total) 230 860

Quantile regression for MIBI and chloride

Data collected 2006-07

Impacts to macroinvertebrate community evident around 141 mg/L

141 mg/L

0

200

400

600

800

1000

1200

10/14 11/3 11/23 12/13 1/2 1/22 2/11 3/3

Ch

lori

de

Co

nce

ntr

atio

n (

mg

/L)

Date

Winter 2007-08

Winter 2008-09

Winter 2009-10

500 mg/L Chloride Standard

0

50

100

150

200

250

2006 2009 2012

Snow in inches

Average Chloride mg/l

Flow ft3

Val

ue

Snowfall, Average Chloride Concentration, & Flow West Branch DuPage River

Year

Federal Clean Water Act - USEPA Waters shall be “fishable” and “swimmable”

Illinois Environmental Protection Agency Administers programs and NPDES permits

Identifies impaired waters - §303(d) List

Develops TMDLs for impaired waters County / Municipalities

NPDES Phase II stormwater permit holders

Implement best management practices

Maximum amount of a pollutant that a water body can receive while meeting water quality standards for its designated use

A chloride TMDL should: Estimate chloride loads from all sources

Determine the capacity of the water bodies to contain that loading without violating the standards

Develop an implementation plan to reduce chloride loads in order to meet the water quality standard

IEPA TMDLs recommend chloride load reductions

West Branch DuPage River - 35% reduction

Salt Creek - 14% reduction

▪ 41% for Addison Creek tributary and 8% remainder

Tons Cl- / yr West Branch Salt Creek Total

TMDL Target 13,710 13,275 26,985

TMDL Baseline 21,100 15,478 36,578

DRSCW Baseline 21,200 32,600 53,800

Groundwater impacts Taste and odor concerns Hypertension

Pet impacts Ingestion Paw health

Wildlife impacts Consumption Vehicular accidents

Vegetation impacts Osmotic stress Reduced species diversity

Driver training Salt spreader

calibration Appropriate

application rates Anti-ice Equipment updates Control salt spread

width Prioritize road system Pre-wet deicer

0.0%

10.0%

20.0%

30.0%

40.0%

50.0%

60.0%

70.0%

80.0%

90.0%

± 0' - 4' ± 4' - 8' ± 8' - 12' ± 12' - 24'

Untreated

Treated

Source-Michigan DOT Salt Bounce and Scatter Study PROJECT SUMMARY REPORT Final November 2012

Ave

rag

e P

erce

nt W

eig

ht

Dis

trib

uti

on

Average Salt Displacement

Pre-Wetting Efficiency: Bounce and Scatter at 25 mph with a Conveyor System

How ice control chemicals work

Phase Diagram - Chlorides

-10

-5

0

5

10

15

20

25

30

35

0 5 10 15 20 25 30 35 40

% Chloride (by weight)

Tem

peratu

re (

F)

Brine

Slush (Solution & Ice)

Solution & Salt

Phase Diagrams - Chlorides

-80

-60

-40

-20

0

20

40

0 5 10 15 20 25 30 35 40

% Chloride (by weight)

Tem

pera

ture

(F

)

Sodium Chloride

Magnesium Chloride

Calcium Chloride

Salt Creek

West Branch DuPage

River

• Salt Creek and West Branch DuPage River have been under a chloride TMDL since 2004 • Local agencies have been working aggressively to lower chlorides from winter deicing operations since before 2007 ¯

0 2 4 6 81Miles

EOWA and DRSCW Area Map

Legend

EOWA_Preferred_Alternative_Option A

Aquatic Life Attainment

Full

Non

Partial

Water Ways

DRSCW_Watersheds

25 miles of mainline improvements

16 service interchanges

4 system interchanges

16 miles of arterial improvements

Provisions for transit and bicycle/ pedestrian facilities

EOWA Project requires a minimum of no net increase in chlorides

Discharges into impaired waterways

§404 and §401 certification applications submitted to USACE and IEPA

Need for chloride offset program created Lane Miles Salt Applied

(tons/yr) Increase from

Existing (tons/yr)

Existing Condition 159 3,959 N/A

Following EOWA Project Construction

264 7,847 3,888

Impact to WBDR and SC Watersheds

N/A N/A 1,482

Two steps to achieve no net increase

Tollway modify current practices

▪ Estimated reduction of 20%

Remaining increase in loading offset by reductions from communities adjacent to the EOWA Project (Tier 1 Communities)

▪ Offsets at a minimum ratio of 1-1.25

▪ Reduction target of 1,853 tons of salt, annually

Estimated Increased Loading by Receiving Stream

City or Village

Tons of Salt

Bensenville 116

Elk Grove 573

Elmhurst 208

Hanover Park 13

Itasca 488

Roselle 209

Schaumburg 102

Wood Dale 140

TOTAL 1,853

Analyze existing conditions, existing deicing practices, and planned highway improvements

Adopt salt reduction strategies Enhanced training, improved materials use, and

equipment upgrades Document salt application rates (per lane

mile), application totals, and calibration logs Conduct long term monitoring

Documents salt usage and stream conditions

Tollway:

Provide ongoing financial assistance supporting capital investments of alternative deicing methods for municipalities

DRSCW: Determine baseline

conditions through appropriate studies with stakeholders ▪ Includes sampling, data

analysis, and flow evaluation

Determine opportunities for improving deicing practices through surveys and interviews with stakeholders

Set priorities, track offset progress, and establish a timeframe for achievement with concurrence from IEPA

Establish training and certifications for operators that enhance awareness of best practices for snow and ice management

Report, to IEPA on an annual basis, the resulting efforts and success of the program Success measured primarily by application rate

and totals reported

Consideration given to ambient monitoring

EOWA Project estimated to increase salt application in the West Branch DuPage River and Salt Creek watersheds by 1,482 tons, annually

Equal to 1,853 tons when 1.25 safety factor considered

Reduction potential of 8,372 tons per year

Assumes application rate of 14 tons/lane mile/year

Reduction attributed to pre-wetting is 25%

▪ 5,233 tons/year

Reduction attributed to anti-icing is 15%

▪ 3,140 tons/year

Robert.Swanson@dupageco.org 630.407.6720