Conditions and Performance Chapter Listing

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Introduction

Summary

Road Conditions

Bridge Conditions

Transit System Conditions

Pavement Condition by Functional System

As was mentioned in Chapter 2, the functional system for approximately 68.9 percent of total mileage is "local." Nevertheless, roads classified as "Interstate" have the largest percentage of VMT, followed by minor arterials and major collectors. Therefore, ride quality on Interstate routes affects more users than ride quality on lower functional systems. Interstate mileage in rural areas is 57.0 percent "very good" or "good," 39.2 percent "mediocre" or "fair" and 3.7 percent "poor." In urban areas on the other hand, Interstate mileage is 40.5 percent "very good" or "good," 50.3 percent "mediocre" or "fair" and 9.2 percent "poor." Regarding minor arterials, rural areas have a slightly lower percentage of "poor" roads and a slightly higher percentage of "mediocre" or "fair" roads compared to urban areas. The urban areas also have a higher percentage of collector roads in "poor" condition and a lower percentage of collector roads in "very good" or "good" condition compared to rural areas. Exhibits 3-7 & 3-8 contain the portion of rural and urban pavement in the various condition categories, respectively.

Exhibit 3-7. Rural Pavement Condition, by Functional System, 1997

Exhibit 3-8. Urban Pavement Condition, by Functional System, 1997

A historical view helps clarify where pavement improvements are occurring and at what rate. Exhibits 39 and 310 list the pavement condition by category, functional system and location from 1993 to 1997. The data table and graphs illustrate that pavement conditions have changed in a variety of ways. For example, since 1993, the percentage of Interstate miles in rural areas characterized as "very good" and "good" has increased from 50.7 percent to 57.0 percent while the percentage characterized as "poor" has decreased from 6.9 percent to 3.7 percent. On the other hand, the percentage of Interstate miles in urban areas characterized as "very good" and "good" has decreased from 45.3 percent to 40.5 percent while the percentage characterized as "poor" has only slightly decreased from 9.5 percent to 9.2 percent. One consistent trend is the faster rate of pavement condition improvement in rural areas versus urban areas. For example, since 1993, the percentage of minor arterial miles in rural areas characterized as "poor" fell from 11.0 percent to 2.2 percent while the percentage in urban areas only fell from 7.9 percent to 7.3 percent. Exhibits 3-9 and 3-10 also identify the portion of Interstate pavements that meet the FHWA Strategic Plan standard for "acceptable ride quality" on the NHS.

Exhibit 3-9. Rural Pavement Condition by Functional System, 1993-1997

Exhibit 3-10. Urban Pavement Condition by Functional System, 1993-1997

Exhibit 3-11

Percentage of Interstate Miles with Acceptable Ride Quality, 1997

Combining the rural and urban Interstate data illustrates that overall our Interstate pavement performance has improved since 1993. Exhibit 3-11 traces the percentage of Interstate miles in "acceptable ride quality." The percentage of all Interstate mileage with "acceptable ride quality" increased from 91.2 percent in 1993 to 92.4 percent in 1997.