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Air Quality-What's All The Fuss About?
Prepared By: James E. Scapellato
Regional Consultant
American Concrete Pavement Association

Atlantans used to brag about its highway system, saying you could travel anywhere in the city in under thirty minutes-whether it was from the north end of Roswell to the airport was no matter. Interstate 85 was four lanes and highway 400 didn't even exist yet. Atlanta was touted as one of the most heavily wooded metropolitan area in America. However, thirty years later, this golden period is no longer. Traffic has gotten unbearable and urban sprawl is a way of life throughout the entire metro area. In the last several decades, the city has lost well over three hundred thousand acres of vegetation because of sprawl causing Atlanta to sometimes be referred to as "Hotlanta". The urban heat island effect has made the city the sixth worst in the nation in air quality, according to the American Lung Association. Air quality has gotten so bad that the Federal government in 1998 withheld 600 million dollars in funds to build new or improved roads until Atlanta took measured steps to reduce the urban heat island effects. The inability to build roads causes more congestion; the congestion, therefore, causes more pollution, and the paradox becomes evident. Thus, the transportation industry is constantly struggling to balance transportation needs with environment protection and enhancement.

First discovered in London during the 1800s, the urban heat island phenomenon has become a focal point in many southeastern cities. Atlanta serves as a prime example. The city's population has grown 65% since 1970 to well over 3 million, and as a result, this once wooded metropolis lost over 16% of its tree canopy between 1973 and 1992. The upset to the land-energy balance has resulted in a 6-12 degree average increase in temperature versus nearby undeveloped countryside, thus producing a variety of problems with smog, energy demand, and air/water quality which caused the EPA to invoke the ban of federal highway spending.

With the recent U .S. Supreme Court ruling upholding EPA's authority to issue broad-based air quality standards, compliance with these standards becomes a critical health and economic productivity issue for the country. Despite that 11% of the Nation's Gross Domestic Product is driven by investment in highways, urban heat island consequences are serious as the Federal Highway Administration would attest. The FHWA predicts that under the new eight-hour ozone standard issued by the EPA in 1997, the number of counties failing to meet the Federal air quality standards will increase from 414 to 656. What this means is that there will be a potential withholding of Federal funds for highway improvements in an additional 52 urban areas, comprising 242 counties because they will be designated as "non-attainment areas" and in 29 areas already categorized as non-attainment, the boundaries will be expanded. For example, the Atlanta region currently has 13 counties included in the non-attainment area, but under the new standard, that number jumps to 21. The DOT in North Carolina predicts that they would be required to halt work on 139 road projects with a net cost of $1.7 billion under EPA's proposed air quality standards.

Consequently, the concrete industries have joined forces, promoting recognition of and education about the importance of air quality attainment through better management and control of urban heat island build-up. This call for action has resulted in local environmental organizations, such as Trees Atlanta (who replenish the tree population in new developments), as well as national organizations like American Concrete Pavement Association, to join forces to help ensure that Federal funding will not be halted for needed road improvement projects. The use of lighter and more reflective surfaces such as concrete pavement materials for roads and roofing materials is shown to have immediate effects in reducing urban heat island effects, with tree canopy replenishment offering most tangible long-term solutions. Scientists at Berkeley National Laboratory have run computer simulations with tree replenishment and reflective surface solutions in Los Angeles and have determined that trees and lightened surfaces in only 15% of the test area produced a six-degree drop in temperature at 3 pm. With increased awareness and the approval of State Implementation Plan credits by the EPA, cool communities initiatives coupled with responsible design and development for our cities and surrounding urban areas will result in lower temperatures and thus lower levels of ozone.

It's everyone's responsibility to play a role in achieving clean air and clean water through sensible growth and development!

In Pasco and Hernando Counties north of Tampa, US 19 and US 41 serve as the only major north-south routes. As the population north of Hillsborough County grew in the late 80's and early 90's, these roads were projected to have major capacity shortfalls. The Suncoast Parkway was proposed, to relieve traffic congestion. The project extends 43 miles, from the Veterans Expressway in Hillsborough County, to US 98 in Hernando County. The Parkway was proposed as a multi-lane, limited access toll facility. In 1988, corridor and environmental studies were initiated by FDOT. In 1992, the preferred alignment was presented at a public hearing. After the hearing, the Turnpike District proceeded with preliminary design for six sections of this project in 1994.

The proposed alignment had major interchanges at the Veterans Expressway, SR54, SR52, and SR50. The project started in residential areas in Hillsborough County, and proceeded through mostly agricultural land in Pasco and Hernando Counties. To streamline the permitting process, quarterly partnering meeting were held with the State permitting agencies. Solutions were found that included multiple wildlife crossings, and creation of a 10,000-acre mitigation site in Pasco County.

There were also aesthetic guidelines developed to promote a parkway environment. These treatments included weathering steel bridges and guardrail, special R.E. wall panels with logo, and tubular sign structures. The area between the slope limits and right-of-way line was not cleared, in order to provide a natural environment along the Parkway. A 30-mile bike trail, extending from SR54 to SR50, was also included in the plans.

Construction started in 1998 on five of the six sections. The Parkway was open to traffic from the Veteran's Expressway to State Route 50, including the bike trail, in March of 2001. The remaining section, from SR 50 to US 98, was opened in August, 2001. This project was the first Turnpike project to include express toll lanes utilizing the SunPass system. The Suncoast Parkway is an excellent example of teamwork between the engineering and construction communities to provide another major transportation corridor in the State of Florida.

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