top of page

Chicago South Suburban Airport Social Benefits Social Costs Analysis

July 23, 2023

A Social Benefits-Social Costs Analysis (SBSCA) was conducted of the proposed South Suburban Airport (SSA) in Will County, Illinois.  The analysis assumed planning/engineering/construction from 2010-2030, operations beginning in 2030, and continuing for 20 years through 2050. The SBSCA only assumes implementation of the inaugural airport and not the ultimate buildout as the latter does not appear feasible during the period of analysis. Sources of information and methodologies are shown below. All figures are in 2023 dollars. Supplemental analysis is also provided.


- Airport Master Plan for the SSA, Socioeconomic Impact Assessment of Alternative Build No-Build Forecasts for the SSA Inaugural Airport Program (Master Plan), ACG: al-Chalabi Group, dated 2-28-06;


- Illinois DOT/AECOM SSA Financial Feasibility Report (FFR), dated 5-20-13;


- Record of Decision for Tier 1: FAA Site Approval and Land Acquisition by the State of Illinois, Proposed SSA, Will County, Illinois, dated 7-22-02;


- U.S. DOT Benefit-Cost Analysis Guidance for Discretionary Grant Programs (U.S. DOT BCA Guidance), dated March 2022 (;  


- U.S. DOT Benefit-Cost Guidance for Discretionary Grant Programs (BCA Guide), dated January 2023 (  


- FAA Airport Benefit-Cost Analysis Guidance (FAA BCA Guide), dated September 16, 2020 (

Other sources are identified in these notations.


1.  Capital Costs:  Annual Illinois Comptroller records document the acquisition of land from 2010-2021 totaling about $137.5M. The FFR outlines about $702.5M capital costs plus $129.4M (2013 $) in debt service mainly for construction over the period of 2015-2024 and through 2043, respectively. This SBSCA assumes construction from 2023-2032 with undiscounted capital costs totaling about $913.3M (2023 $), which is the FFR capital costs adjusted for inflation. Debt service costs are not included per the FAA BCA Guidance, p. 75. Thus, the total estimated undiscounted capital costs are $913.3M + $137.5M = $1,050.8M (2023 $). 


2. Operating and Maintenance (O&M) Costs:  Annual costs of about $11.7M (2023 $) are estimated based upon the Chicago/Rockford International Airport (RFD)(Annual Comprehensive Financial Report, dated 2022, O&M costs of about $11.2M (2022 $).


3. Farm Crops Production Costs:  The inaugural SSA footprint is estimated at 5,200 acres based upon the Master Plan for the SSA, Selection of IDOT Preferred Inaugural Airport Configuration (p. 1). It is assumed that 4,251 acres of this is tillable (remaining pastureland) based on the FFR, p. 15. Farm revenue per acre is based upon the 2017 USDA Census of Agriculture (Illinois, Table 2 & Table 8), total farm sales in Will County inflated to 2023 $, which is $766/acre ($165,941,000/216,593 acres).

Ecological Acreage Loss Costs: The ecological value assumed is $4,892 (2023 $) per acre [($9,000 Canadian per hectare/2.47 acres conversion)/U.S. 1.4 exchange rate] or $2,602 per acre in 1997 $) or the mid-range of conversion of pasture/farmland to settlement/road buffer and pavement (Bein, Peter. 1997. “Monetization of Environmental Impacts of Roads,” Chapter 4, Shadow Price Estimates, Table 4.13).


Of note is that the Will County Forest Preserve District estimated 2023 budget revenues are about $61M for 23,000 acres or about $2,652 per acre (


Induced development is based upon the Master Plan, Table 37, page 65 estimate of population growth in Will County due to the SSA. The Master Plan forecasted a regional population increase of about 2.8 percent (300,861/10,631,213) from 2000 to 2030 due to the SSA. About 1/3rd of this was forecast for Will County. Exhibit 5 in the Master Plan shows that the vast majority of population increases associated with the SSA would be in exurban areas. Given that in 2022 Will County had roughly  627,081 in UA population on 326,767 urban acres (1.9 persons per acre), a conservative assumption was made that SSA would induce about 100,000 persons/1.9 acres per person on 52,109 farmland acres by 2050. 


4. Population estimates from the U.S. census for 2020-2022 are for a presumed market area of 33 Illinois, Indiana and Wisconsin counties encompassing SSA, ORD, MDW, RFD, and GYY airports. The 2023-2050 low end estimates were based upon the 2000-2022 total annual compound growth rate for these counties of 0.14%. The high end estimates are based upon estimates from the various regional planning agencies for the applicable counties and on the 2000-2022 trend for the remaining counties. Mid-range population growth was then calculated.


5. Actual and estimated total air operations capacity or number of flights capacity for ORD, MDW, RFD, and GYY combined are based upon FAA average daily capacity (ADC) data "called rates" at Core 30 Airports during the period of FY2015-2019 (Air Traffic by the Numbers, p. 14, FAA's operational arm, or Air Traffic Organization (ATO), uses ADC to determine an airport's capacity during one day. Thus, the annual ORD and MDW capacity data for this SBSCA is the actual data extrapolated over 365 days.  For the Core 30 Airports, number of runways at each along with their flight capacities were used to calculate the average flight capacity per runway (488 daily and 178,132 annual) and then applied to RFD and GYY airports, which each have two runways. Therefore, total estimated annual flight capacity for the four airports is 2,319,987 (ORD 1,218,370; MDW 389,090; RFD; 356,264; and GYY 356,264).


Actual 2000-2019 total air operations and enplanements for ORD, MDW, RFD, and GYY were obtained from FAA's Operations Network (OPSNET) data ( The average per capita number of flights were calculated for the 33-county market area and used to estimate total air operations for the four airports through 2050 under the low, mid-range, and high population growth scenarios.

FAA APO Terminal Area Forecast Detail air operations and enplanement reports for ORD, MDW, RFD, and GYY were also retrieved (

FAA OPSNET data documents 2000-2019 volume-related delays, i.e. number of flight delays and number of minutes due to lack of capacity. The calculated per flight average number of delays and number of minutes delayed was calculated for ORD, MDW, RFD, and GYY together. These ratios were used to predict a rising number of future delays and minutes delayed over time if the SSA project is not implemented. This methodology is reasonable as the three population-based and one FAA-based total air operations estimates all do not exceed the estimated four-airport total capacity. An all-purposes travel time value of $54.54 (2023) based upon FAA Values for FAA Investment and Regulatory Decisions, A Guide, Table ES-1, p. ES-3, (ECONOMICVALUESFORFAAINVESTMENTANDREGULATORYDECISIONS10032007.pdf)  was used to calculate the estimated amount of passenger delay due to not implementing the SSA project.


Cargo landed weight was obtained for ORD, MDW, RFD, and GYY from FAA FAICS data for 2000-2019. A trend function was used to estimate future cargo weight through 2050. Per the Chicago Department of Aviation, O'Hare handles more than 2 million metric tonnes of cargo with a value of more than $200 billion annually. Accordingly, an assumption was made that the average value per MT ton of cargo is $100,000.  The value of delayed freight was then calculated based upon the estimated delay trend due to volume. Per FAA BCA Guidance (p. 63), total cargo delay cost is (($ value of delayed freight x hours of delay)/8,760 hours in 1 year)) X 7% which is OMB's estimated return to capital in U.S. economy.


6. Aircraft variable hourly operating costs including crew are from the ECONOMIC VALUES FOR FAA INVESTMENT AND REGULATORY DECISIONS, A GUIDE (10-3-2007) - GRA, Incorporated as follows:  Air Carrier $6,000 (2002 $), $10,226 (2023 $)(Tables 4-3, 4-4, and 4-5); Air Taxi/Commuter/General Aviation $362 (2002 $), $617 (2023 $)(Tables 4-10, 4-17); and Military $6,138 (2002 $), $10,461 ($2023 $)(Tables 4-13, 4-20). This data was applied to the aforementioned estimated volume delays and proportion of aircraft type to calculate predicted variable operating costs without the SSA project. It was assumed that the SSA would alleviate all of these delays.


7. Assumed respective road passenger vehicle variable operating costs are $4,151/15,000 miles annually = $0.277 and per VMT and $6,578/15,000 miles = $0.439 (Bureau of Labor Statistics, American Automobile Association, Newsroom, Your Driving Costs Fact Sheet, available at as of Aug. 15, 2022). Vehicles miles travel (VMT) data was obtained from respective state DOT’s by county. Since the project is expected to induce 100,000 people to move to Will County in exurban areas, it was assumed that per capita VMT (PCVMT) there for these persons would increase conservatively by 10 percent more than the no-build. Of note is that Will County PCVMT is more than 50 percent higher than Cook County (5,734 vs. 8,613 in 2021). Will County vehicle ownership per person is roughly double that of Cook County (0.675 vs. 0.329). It was assumed that new Will County project-induced residency would increase vehicle ownership rate for those persons by one-half this or 0.173. Therefore, induced residential vehicle operating costs were calculated by increasing the 100,000 population rise incrementally from 2023-2050 and adding the variable operating and fixed operating cost increases from the rise in both VMT and vehicle ownership. 


8. The TRB Transportation Benefit-Cost Analysis web site provides noise impact values per VMT for vehicles from several studies [, referencing: Todd Litman (2010), "Noise," Transportation Cost and Benefit Analysis, Victoria Transport Policy Institute (, available at]. Dollar values for noise impacts in these cited studies show the following per VMT (converted to 2023 $):  auto (electric & gas/diesel, $0.004 and $0.10 or mid-level $0.058).


9. Aircraft emissions calculations were performed for the reduction in CO2 and NOX due to the SSA project. Dollar values per MT are from the USDOT BCA Guide, Table A6. An assumption was made that all aircraft benefiting from reduced delay and emissions are large jets. Thus, this is considered a high-end calculation. Estimated jet CO2 and NOX emissions per minute are from the following respective publications:  Study of Mobile Source Emissions: Macdonald-Cartier International Airport, p. 50, Table 28 (; and Environmental Impact of Delay, p. 9, Table 9 (


10. Automobile and light truck emissions calculations were performed for increases in CO2, NOX, PM2.5, and VOC. Dollar values per MT for each are from the USDOT BCA Guide, Table A6 (VOC value is from the 2017 BCA Guide). Emissions assumed per VMT were from the following sources:


CO2: 347 g/mile (US EPA 2022 Automotive Trends Report, Per the USDOT  BCA guidance, the CO2 values were only discounted at the 3 percent rate but also used in the 5 and 7 percent benefit columns as disbenefits.


NOx:  0.03 g/mile (US EPA Light Duty Vehicle Emissions,  

PM2.5:  0.003 g/mile (US EPA Light Duty Vehicle Emissions,  Also, per the U.S.DOT BCA Guidance, a value was not calculated for PM10.


VOC:  1.129 g/mile mid-range auto/light truck (2008 US EPA Average Annual Emissions and Fuel Consumption for Gasoline-Fueled Passenger Cars and Light Trucks).


11. Resource Consumption Costs:  These are external costs of transport resource production (primarily petroleum) or the social benefits of resource conservation.  These include military security costs for foreign oil, trade deficits from its import, environmental damages from oil extraction, oil company tax subsidies, and human health risks from injuries and pollution during extraction.  Depletion of non-renewable resources for future generations is an externality as well although it is not costed. See the VTPI Transportation Cost and Benefit Analysis II - Resource Consumption External Costs ( The VTPI, Transportation Cost Analysis Spreadsheet has default cost values per VMT as follows in 2007 $ for average travel:  average car $0.039 ($0.059 in 2023 $); light truck/van $0.050 ($0.075 in 2023 $). A mid-range of $0.068 (2023 $) was used.


12. Parking Costs:  The VTPI, Transportation Cost Analysis Spreadsheet has default parking cost values per VMT as follows in 2007 $ for average travel:  car/pickup/van $0.064 ($0.097 2023 $) (internal); $0.060 ($0.090 2023 $)(external) for a total of $0.187 (2023 $).  Internal costs are paid directly by users for residential parking while external costs are off-street parking paid by non-users through increased bundled goods costs and services that includes free/reduced cost parking


13: Health Effects:  Gotschi (2011) documented annual per capita health care costs per inactive person, with the average being $544 in 2008 $ ($786 in 2023 $). Jacobson et al. (2011) studied U.S. licensed driver and obesity rates longitudinal data over the period of 1995-2007. The finding was that an increase of 365 VMT annually per licensed driver is associated with a 2.16 percent increase in the adult obesity rate 6 years later. The Jacobson et al. research outlines the consistency of findings with other research. Although, collectively, these studies have been unable to establish causality. The study used FHWA (2019)( data to estimate the proportion of licensed drivers in the Chicago region. Thus, the study calculated estimated annual costs for changes in inactivity based upon alterations in VMT per the Jacobson et al. research. This does not cover mortality costs from reduced lifespans due to lower cardiovascular activity.


14. Barrier Effects:  These are delay costs to non-motorized travel caused by motorized travel.  See the VTPI Transportation Cost and Benefit Analysis II - Barrier Effect publication ( The VTPI, Transportation Cost Analysis Spreadsheet has default barrier effect cost values per VMT as follows in 2007 $ for average travel:  car/pickup/van $0.014 ($0.021 in 2023 $). The VMT reduction was multiplied by these values accordingly.


15. Transport Diversity:  According to the VTPI Transportation Cost Analysis Spreadsheet, the value per VMT for transportation diversity is $0.007 in 2007 $ ($0.0135 in 2023 $). This represents the benefits of improving transportation options brought about by the Project that reduces overall transportation costs for the public. Additionally, the value measures the extent disadvantaged populations (elderly, low income, minority) are unable to travel due to increased accessibility brought about by improved mode choice.


16. Accident Reduction Benefits:  The most substantive roadway impacts expected due to the project would be in Will County. The 2021 IDOT Summary Crash Report data for Will County shows the number of crashes (13,459), related deaths (ratio of 70/13,459 = 0.0052), injuries (ratio of 4,140/13,459 = 0.3076), vehicles (ratio of 25,719/13,459 – 1.9), and vehicle damage per vehicle ($5,400 per vehicle). This information along with calculated crashes per 100,000 VMT (0.207) and the increase in predicted project-related VMT were used to estimate increases in roadway crashes, deaths, injuries and property damage.   

The value of a statistical life (VSL) estimates are from the U.S. Departmental Guidance on Valuation of a Statistical Life in Economic Analysis ( and US DOT Departmental Guidance, Treatment of the Value of Preventing Fatalities and Injuries in Preparing Economic Analyses ( 

The estimates of injury severity were based in part on the U.S. DOT BCA Guidance, Table A-1: Value of Reduced Fatalities and Injuries monetary values, including 1.44 injuries per accident, and the TIGER Guide, Table 4. KABCO/Unknown – AIS Data Conversion Matrix for injury severity probabilities.  Accordingly, the data on number of road accidents reduced was converted to the Abbreviated Injury Scale (AIS) to determine estimated level of injury by severity rates (none, minor, moderate, serious, severe, critical).


17. Residual: Remaining value of the SSA at the end of 20 years after construction was calculated from the SSA Master Plan - Draft Facilities Implementation Plan, Appendix D - Detailed Breakdown of Inaugural Capital Improvement Program development tasks and cost estimates. Assumptions for useful life of the various components were as follows:  pre-construction/planning - 0 years; earthwork/other foundational - 100 years; roadway surfaces - 15 years; buildings/related structures - 60 years; equipment - 20 years; bridges/aprons - 50 years; road vehicles - 8 years. Value Sources: Residual Values and Appraisal Period in Multimodal Transport Appraisal (lifespan Table 9, p. 35, original source is from a Heathrow Airport financial statement)( and Annual Report and Financial Statements 2019, Heathrow Airport Limited Annual Report (p. 124)(


18. Wider economic benefits or productivity gains:  Per the FAA BCA Guidance (pp. 68-69):  “Relatively few airport projects will be candidates for productivity analysis, in that the project must result in a fundamental change in the cost of doing business. Many productivity gains would already be captured in the BCA – e.g. more efficient use of aircraft and people and other factors of production; any additional gains would be due to a different way of doing business which would have to be documented. Given the early stage of development of this type of analysis, FAA will consider claimed productivity gains separately from conventional BCA results….The Net Benefits of a new airport usually will not exceed the costs that passengers (and other customers) would avoid if they otherwise had to access alternative airports which together or alone can produce the same set of services. So for example, the benefits of a new general aviation airport cannot exceed the benefits users gain by avoiding accessing other existing general aviation and/or commercial airports with the same capabilities (runway length, lighting and approach capabilities, capacity, and other facilities.) Any benefits beyond these access related savings would have to be due to unique productivity gains (in the production of aviation services) or macroeconomic gains that would otherwise not occur nationally, both of which would have to be separately reported. For example, an airport capacity project that stimulated net national demand for aviation services might produce consumer benefits that otherwise would not exist by lowering the full cost of travel by a substantial amount. But this would be highly unusual in a mature aviation market where annual growth rates are typically in the low single digits.”


The 2021 SSA Economic Impacts Report (SSA EIR) by Governors State University and the Chicago Southland Economic Development Corporation was analyzed to determine the extent any costs or benefits from this source could be included. The 2021 SSA EIR calculated estimates for increases in employment, labor income, value added, total output, and tax revenues. Low-case, base-case, and high-case scenarios are provided. However, the SSA EIR does not provide information regarding losses (or foregone gains) that would likely occur for all of these metrics at other regional airports or elsewhere in the region.


Table 1 below is a summary of the SBSCA for the SSA.     

                                                              Table 1 - Chicago South Suburban Airport Social Benefits Social Costs Analysis Summary

Analysis of need for Chicago third airport.
bottom of page