Abstract:
Because of undesirable characteristics of some major arterials such as State Route (SR) 99 north and south of Seattle several cities are implementing redevelopment plans. These redevelopment proposals for SR 99 and other state routes include landscaped medians, many with trees placed close to the roadway in either the median or shoulder areas. However, WSDOT’s clear zone width criterion may not always be met when trees are placed within curbed medians. To address this potential conflict, WSDOT chose to adopt an in-service evaluation process that would study collision, environmental, operational, and maintenance experiences in the field. A report was prepared in 2007 that summarized an analysis of two of the 13 median treatment projects. That report also provided before data and condition information on all median sections. This report summarizes the analysis of five additional sections. Because of changes in the methodology, previously reported accident rates were recalculated to be consistent with the after data from this analysis. Data from the before and after periods were also analyzed at two control locations where no median treatments were installed. Total, fatal, fixed object, pedestrian/bicycle, tree, curb/median and U-turn accident rates were analyzed. The percentages of intersection-related, driveway-related, and other accidents were analyzed. Overall, accidents decreased significantly for the treatment locations, but no other types of accidents showed significant changes at either the treatment or the control locations, except for the percentage of other types of accidents at the control locations, which increased significantly. It appears that the installation of landscaped medians does not have a detrimental effect on safety and may result in an overall decrease in accidents, conclusions consistent with those of the first phase.

Authors:
Briglia, P.M., Howard, Z.N., Fishkin, E., Hallenbeck, M.E., St. Martin, A.

Keywords:
Trees, highway safety, aesthetic design, Context, Sensitive Design, urban design, accident rates, injury, severity

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Abstract:
Arterials such as State Route (SR) 99 north and south of Seattle have characteristics that are considered by many cities to be undesirable. In response, several cities are implementing redevelopment plans to increase road safety, create a more aesthetically pleasing local environment, and enhance the economic vitality and attractiveness of the communities. The cities’ redevelopment proposals for SR 99 and other state routes include landscaped medians, many with trees placed close to the roadway in either the median or shoulder areas. However, WSDOT’s clear zone width criterion may not always be met when trees are placed within curbed medians. To address the desires of cities to implement aesthetic designs, WSDOT chose to adopt an in-service evaluation process that would study collision, environmental, operational, and maintenance experiences in the field. This report summarizes the findings of two of the 13 median treatment projects included in the in-service evaluation of alternative median treatments. It provides before data and condition information on all median sections, but because most of the roadway sections have only recently been improved, it provides after data for only two phases of improvements, those on SR 99 in the City of SeaTac. The conclusions of the before and after analysis on those two sections of roadway indicate that no dramatic changes in roadway safety have occurred as a result of the change from continuous two-way left turn lanes and limited sidewalks to a streetscape that includes full sidewalks and landscaped medians with turn pockets, and where both sidewalks and medians include small trees as part of the landscaping. While no definitive conclusions about the safety impacts of landscaped medians can be drawn at this point in the multi-year in-service evaluation, it can be said that there is no indication that the roadways are less safe than before the landscaping was planted. Therefore, it is recommended that the current in-service evaluation be continued as planned.

Authors:
St.Martin, A., Hallenbeck, M.E., Milton, J., Nee, J.

Keywords:
Trees, highway safety, aesthetic design, Context, Sensitive Design, urban design, accident rates, injury severity

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Abstract:
Arterials such as State Route (SR) 99 north and south of Seattle have characteristics that are considered by many cities to be undesirable. In response, several cities are implementing redevelopment plans to increase the safety of the road, create a more aesthetically pleasing local environment, and enhance the economic vitality and attractiveness of the communities. The cities' redevelopment proposals for SR 99 and other state routes include landscaped medians, many with trees placed close to the roadway in either the median or shoulder areas. However, WSDOT's clear zone width criterion may not always be met when trees are placed within curbed medians. To address the desires of cities to implement aesthetic designs, WSDOT chose to adopt an in-service evaluation process that would study collision, environmental, operational and maintenance experiences in the field. This report summarizes the findings of two of the 13 median treatment projects included in the in-service evaluation of alternative median treatments. It provides before data and condition information on all median sections, but because most of the roadway sections have only recently been improved, it provides after data for only two phases of improvements, those on SR 99 in the City of SeaTac. The conclusions of the before and after analysis on those two sections of roadway indicate that no dramatic changes in roadway safety have occurred as a result of the change from continuous two-way left turn lanes and limited sidewalks to a streetscape that includes full sidewalks and landscaped medians with turn pockets, and where both sidewalks and medians include small trees as part of the landscaping. While no definitive conclusions about the safety impacts of landscaped medians can be drawn at this point in the multi-year in-service evaluation, it can be said that there is no indication that the roadways are less safe than before the landscaping was planted. Therefore, it is recommended that the current in-service evaluation be continued as planned.

Authors:
St. Martin,A., Milton,J., Hallenbeck,M. E., Nee,J.

Keywords:
Trees, highway safety, aesthetic design, Context Sensitive design, urban design, accident rates, injury severity

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Abstract:
To address the need to deliver cost-effective projects while minimizing traffic impacts, the Washington State Department of Transportation (WSDOT) desires to improve their knowledge, awareness and retention of rapid pavement construction tools, materials and methods. This project discusses the implementation, use and experience of using the following items related to rapid pavement construction: CA4PRS (Construction Alternatives for Pavement Rehabilitation Strategies), portland cement concrete (PCC) pavement panel replacement, polymer concrete and traffic closure windows. CA4PRS is a Microsoft Access-based software program for predicting construction productivity for highway rehabilitation/reconstruction. It was tested in two case studies and has proved capable of providing meaningful scheduling and productivity inputs into early project planning. Panel replacement techniques and polymer concrete construction are reviewed (including contractor interviews) in an effort to document past successes and failures as well as key decision points when making future project decisions. Finally, a review of traffic closure windows for rapid construction is presented.

Authors:
Ozolin,B., Muench,S.

Keywords:
accident rates

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Abstract:
WSDOT needs to share information with a wide array of information consumers, including the general public, contractors, vendors, and other government agencies. Trusted partners need access to WSDOT information sources. Partners include Washington and federal government agencies, counties, and cities; consulting firms, contractors, and subcontractors. The objective of this project was to help WSDOT determine how to provide trusted business partners with flexible, secure access to WSDOT systems and data with an access method that is able to meet current and anticipated data sharing requirements.

Authors:
Mason, R.M., Endicott-Popovsky, B., Simon, M., Larson, R.E., McCrea, K.

Keywords:
accident rates

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Abstract:
Floating bridge concrete must be watertight, durable, workable, and must have sufficient cohesiveness to prevent segregation in heavily congested deep walls. The mix design must experience minimal creep and shrinkage to reduce prestress losses, and shrinkage cracking. As a result of recent concrete research, new mixes were created incorporating various quantities of fly ash, silica fume, metakaolin, poly-carboxylate ether superplasticizers, and Caltite waterproofing admixture. This research focuses on concrete with a water binder ratio of 0.33 and a slump in the range of 8 to 9 inches. Workability characteristics of the fresh concrete are analyzed and hardened concrete properties tested in this research are compressive strength, chloride ion permeability, and creep and drying shrinkage properties. It was found that metakaolin was successful in producing mix designs with similar properties as Silica fume modified concrete. Satisfactory strength was achieved through increasing the fly ash and lowering the silica fume contents, though, chloride ion permeability was negatively affected. The removal of silica fume and the inclusion of Caltite decreased the concrete’s resistance to chloride ion permeability and produced concrete that failed to attain the required 28-day ultimate compressive strength of 6500 psi. The second part of this study focuses on developing an experimental setup to evaluate products and construction methods to help prevent water leakage through construction joints in pontoon floating bridges. A pressure system was used to apply significant pressures to concrete test specimens containing a construction joint. Different products and construction methods were used in constructing the joints to determine the most effective methods for preventing water penetration in the field. The testing results have shown compaction effort is the most important factor in water leakage through a joint. Increased compaction in laboratory specimens leads to less water leakage through construction joints. Product selection was ineffective in preventing water leakage if concrete compaction was inadequate.

Authors:
Itani,R., Masad,E., Balko,B., Bayne,B.

Keywords:
concrete, performance, fly ash, silica fume, metakaolin, polycarboxylate, caltite, creep, shrinkage, compressive strength, permeability, construction joint, leakage, waterstop, accident rates, compaction, watertight

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Abstract:
The purpose of this research was to explore the relationship between roadway and roadside accidentrates for Washington State highways to improve the Washington State Department of Transportation's(WSDOT) process of modeling roadway and roadside accident rates and to arrive at possible improvements in the efficiency of WSDOT's safety project programming process.The project tested the use of the seemingly unrelated regression estimation (SURE) model to modelthe roadway and roadside simultaneously. The theoretical advantage of the SURE approach is that it does not impose any a priori assumptions on the explicit linkage between roadway and roadside accident rates, and there is no theoretical support for explicit linkage, either. The data used to derive this model were from a random sample of 500 one-mile sections from the Washington State highway system. Traffic dataincluded traffic volumes, truck compositions, AADT, traffic speeds, and other relevant information.Geometric data included lane, shoulder, median, curve, and intersection information. Historical weather data such as monthly precipitation and temperature were collected from the National Oceanic and Atmospheric Administration database.In comparing significant explanatory variables between the roadway accident rate and roadsideaccident rate models, very few variables were common. This confirms that it is preferable to specifyseparate functional forms for roadway and roadside accident rates. Empirical results indicated thatcorrelation between roadway and roadside accident rates was insignificant, indicating that efficiency gainsfrom the SURE model would be minimal. The important finding from a programming standpoint is thatjointly modeling the roadway and roadside simultaneously would not result in significant efficiencyimprovements in comparison to the current state-of-the-practice in Washington State.

Authors:
Chayanan,S., Nebergall,M., Shankar,V., Juvva,N., Ouyang,Y.

Keywords:
roadway, roadside, accident rates, safety programming, research, Washington, Washington state, highway, transportation, WSDOT, modeling, safety, regression, linkage, data, traffic, traffic data, volume, truck, speed, median, temperature, database, models

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External Links: http://www.wsdot.wa.gov/research/reports/fullreports/562.1.pdf http://wsdot.wa.gov/Research/Reports/500/562.1.htm

Abstract:
This report documents the findings of regional precipitation-frequency analyses of 24-hour and 2-hour precipitation annual maxima for western Washington. It also describes the procedure used for spatial mapping of the precipitation-frequency estimates for selected recurrence intervals.This study is an update of the information contained in the precipitation-frequency atlas published by the National Weather Service in l973. Data collection for the NWS study ended in 1966, and this study includes the 34-years of record collected since 1966. These additional data provide a precipitation database with more than double the record length than was available in the original NWS study.Since the original study, major advances have been made in the methods for statistical analysis of precipitation annual maxima, and for spatial mapping of precipitation in complex terrain. Specifically, L-Moment statistical analysis techniques conducted with a regional framework have greatly improved the reliability of precipitation magnitude-frequency estimates, particularly for rare storm events. Development of the PRISM model incorporating digital terrain data has also improved the spatial mapping of precipitation and increased the reliability of estimating precipitation in the broad areas between precipitation measurement stations. These methodologies are particularly effective in areas with high topographic and climatic variability such as in western Washington, where mean annual precipitation varies from less than 20-inches to over 200-inches. Both of these methodologies have been utilized in conducting the precipitation-frequency analyses and in developing the isopluvial maps for selected recurrence intervals.

Authors:
Schaefer,M., Barker,B., Taylor,G., Wallis,J.

Keywords:
accident rates

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External Links: http://www.wsdot.wa.gov/research/reports/fullreports/544.1.pdf http://wsdot.wa.gov/Research/Reports/500/544.1.htm

Abstract:
In 1998, the Washington State Department of Transportation (WSDOT) with funding assistance from the Federal Highway Administation, constructed a groin and underwater dike adjacent to State Route 105 on the north side of Willapa Bay in the vicinity of North Beach. The structure was designed to arrest the northward migration of a deep ebb tidal channel that, if continued to move northward, threatened to erode the only transportation link connecting Tokeland and the Shoalwater Indian Reservation with Grayland and Westport. The structure was built in two segments: an above-water portion, generally referred to as the groin (locally known as Jacobson's Jetty), and an underwater portion, referred to as the dike. As a condition of the emergency construction authorization, WSDOT agreed to conduct a biological monitoring program to evaluate the effect of the structure on the habitat and migration habits of salmonids that pass through the estuary and coastal area on their way in or out of Willapa Bay.

Authors:
Miller,M. C., Williams,G. D., O'Rourke,L. K., Sargeant,S. L., Southard,J. A.

Keywords:
accident rates

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External Links: http://www.wsdot.wa.gov/research/reports/fullreports/521.3.pdf http://wsdot.wa.gov/Research/Reports/500/521.3.htm

Abstract:
Hydrologic, meteorological, and other environmental data were collected from water years 1998 to 2000 near two recently constructed storm-water retention basins near DuPont, Washington. A mixture of gypsum, grass seeds, and mulch was added to soils of one of the basins to slow infiltration by water. Six monitoring wells were installed in May 1997 near the two retention basins: one upgradient of the basins, four adjacent to the basin without gypsum, and one near the basin with the gypsum soil amendment. Water-quality samples were collected to monitor possible changes in ground-water chemistry. Ground-water levels in selected wells were measured both manually with a steel tape and with automatic monitoring systems. Water level of an intermittent pond in the gypsum-treated basin was monitored, as were selected meteorological and other environmental variables. The hydrologic, meteorological, and other environmental data are presented in this report.

Authors:
Bidlake,W. R., Frans,L. M.

Keywords:
accident rates

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External Links: http://www.wsdot.wa.gov/research/reports/fullreports/512.3.pdf http://wsdot.wa.gov/Research/Reports/500/512.3.htm

Abstract:
Many older bridges in Washington State contain split reinforced concrete columns as common members between adjacent bridge sections. The split detail was incorporated in columns to allow for movements in the bridge due to temperature and shrinkage effects. It is expected that these split columns will perform poorly in the event of a significant earthquake. This study investigated retrofitting measures for improving the seismic performance of existing split columns.Experimental tests were conducted on one-third scale split column specimens which were representative of the split column present in the Spokane Street Overcrossing near Seattle. Various retrofit measures were evalauted. Specimen performance was evaluated on the basis of load capacity, displacement ductility, and hysteretic behavior.Tests on specimens representing as-built conditions revealed vulnerabilities that have previously been observed in the field or are expected to occur during a major earthquake. Poor performance evident in the as-built specimens included crack propagation from the base of the split, lap splice degradation, and shear failure in the split sections.Retrofit design focused on enhancing the column seismic performance while at the same time preserving as much of the gap between the split sections as possible. Procedures were developed for the design of steel jacketing as a retrofit measure for the split columns. Circular jacketing was used for the section below the split and for retrofitting a deficient lap splice. "D" shaped jackets were used for the split sections to provide confinement in flexural hinging regions and to increase shear strength. Tests on specimens retrofitted with the steel jacketing showed significant improvements in performance when compared to that for the as-built specimens.Three compaanies who manufacture composite retrofit systems were invited to participate in this project. Each company was provided with unretrofitted specimens for which they designed and installed their company's retrofit system. While some differences in performance were obtained with the various retrofit systems, all retrofitted specimens showed significant improvements in performance when compared to that for the as-built specimen.

Authors:
McLean,D. I., El-Aaarag,M. H., Rogness,P. D.

Keywords:
accident rates

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Abstract:
There are several treatments available for the remediation of petroleum hydrocarbon-contaminated soil. Some use chemical or mechanical methods, others make use of incineration, and still others use biological materials, either native or introduced, to remove or degrade the contaminants. Battelle Marine Sciences Laboratory (MSL) and the Washington State Deparment of Transportation (WSDOT) conducted a 4-month experiment to compare the efficacy of three different biological approaches--mycoremediation, bioremediation, and enhanced bacterial remediation--used under open environmental exposure to threat three excavated, aged-oil-contaminated soils stored at the WSDOT Maintenance Yard, Bellingham, Washington. The MSL designed the experiment in collaboration with WSDOT, and the project was jointly funded. At the end of this experiment, the results were not conclusive in distinguishing the outcome of the various treatments; none appeared to meet the prescribed criterion for success, namely attainment of the Method A Cleanup Level of total petroleum hydrocarbons (TPH) prescribed by the Washington State Department of Ecology (WSDOE) in Washington Administrative Code (WAC) 173-340 (WAC 1996) and Ecology Publication No. ECY-97-600 (WSDOE 1997) during the allotted time period. However, much useful information was gained by the exercise,and progress was made in understanding the variables that challenge the transition from mesocosm to large-scale deployment of remediation biotechnology. This study also showed that toxocity testing of treated and control sols using native plants and invertebrates can offer valuable information on the suitability of treated substrate for beneficial uses.

Authors:
Thomas,S., Becker,P., Pinza,M. R., Word,J. Q.

Keywords:
accident rates

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Abstract:
The construction and pressure testing of a field instlation of Contech-A 2000 PVC sewer pipe are documented in this report.

Authors:
Miner,C. M.

Keywords:
accident rates

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Abstract:


Authors:
Mahoney,J. P., Chatti,K., Winters,B. C., Moran,T. J.

Keywords:
accident rates

Abstract:
This final report details the field performance of a Ceva-Crete Expansion Joint System on an I-5 bridge in Olympia, WA. The Ceva-Crete system employs an elastomeric concrete that is vulcanized in place to handle impact loads on the joint and a low density closed cell material (Evazote 50) that is epoxied to the steel nosing of the joint, to act as the seal. The performance of the joint system was evaluated after a five year period.

Authors:
Roper,T. H., Henley,E. H., Jr.

Keywords:
accident rates

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Abstract:


Authors:
McCloskey,R. J., Tiedemann,R. B.

Keywords:
accident rates

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Abstract:
The construction and performance history are described for a rubberized, open-graded pavement placed on SR-520 near Kirkland, Washington. The section has lasted longer than the average conventional open-graded pavement, but it is not clear that the addition of the rubber was the only contributing factor in the increased life of the section.

Authors:
Livingston,J., Schultz,R. L.

Keywords:
accident rates

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Abstract:
A loose debris avalanche deposit, resulting from the 1980 eruption of Mt. St. Helens, was encountered during the foundation geotechnical investigation for Bridge 12 on Spirit Lake Memorial Highway (SR 504) in the Mt. St. Helens National Volcanic Monument, Washington. The deposit was determined to be at risk of experiencing liquefaction and/or dynamic settlement during the design seismic event for the structure (Richter magnitude 6.5 and peak ground acceleration 0.55g). The experimental use of deep blasting was selected by the Washington State Department of Transportation and approved by the Federal highway Administration, to densify the deposit full depth (up to 43 meters) for the purpose of mitigation the liquefaction and dynamic settlement risks. The contract for the work utilized a test section to evaluate the blast design. Revisions were made to the blast design based on the results of the test section blasting, and production blasting was completed in December 1992. NUmerous instruments were used to monitor and quantify the results of the blast densification. Standard Penetration Testing (SPT) before blasting indicated average, corrected blowcounts of about eight full depth in the deposit. Post blasting SPT blowcounts increased to above the goal of about 25 in the upper 15 meters of the deposit, and to above about 20 below 15 meters. Modified Becker Penetration Testing corroborated the SPT results. Total ground surface settlement of up to 1.5 meters was observed. Volumetric compressive strains on the order of about 8% were determined on the basis of surface settlement and slope iclinometer measurements.

Authors:
Kimmerling,R. E.

Keywords:
accident rates

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Abstract:
A pavement tour of modified asphalt binders was conducted in April and May of 1993 by various personnel of the Construction and Materials sections of the Washington State Department of Transportation and the Asphalt Paving Association of Washington. The tour participants\' comments for each section of pavement are summarized and a brief discussion fo the relative performance of the sections is presented

Authors:
Anderson,K. W.

Keywords:
accident rates

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Abstract:
This study provides recommendations for using the Road Rater Model 400B and the PEDMOD (Pavement Evaluation and Design Model) program for pavement evaluation and design. In order to address seasonal variation in pavement response for pavement evaluation and design, 36 test sections were established in 8 counties in Washington State. Road Rater deflation data was collected monthly on the test sections for a period of one year. The pavement evaluation and design capabilities in the PEDMOD program utilize resiliant material properties obtained from WESDEF, a backcalculation analysis program developed at the U.S. Army Corps of Engineers Waterways Experiment Station , which is contained within the PEDMOD program. Results obtained from the WESDEF using the Road Rater deflection data collected on the test sections indicate that it is difficult to obtain meaningful resilient material properties for pavement layer materials. Results of the analysis of deflection data for seasonal variability indicate that some general trends in variation in maximum deflection and subgrade resilient modulus occurred during the 12-month testing period, however the test sections should be maintained for a longer period of time to develop specific seasonal correction factors. Recommendations are provided for calibrating the Road Rater and performing systemwide design level and deflection testing as well as recommendations for the use of PEDMOD. In addition, recommendations are provided for alternative techniques for pavement evaluation using parameters obtained directly from Road Rater deflection basins.

Authors:
Rutherford,M.

Keywords:
accident rates

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Abstract:
Since 1998, the Washington State Department of Transportaiton (WSDOT) has been testing the use of weather information technologies in support of snow and ice control operations. In 1989 WSDOT contracted with a private meteorological service, had road thermography conducted on state roads in Area 5 of District 1, and installed sensor systems in four Area 5 locations. The thermography was also used as a basis for obtaining forecast temperature profiles for the state roads on which the thermographic analysis had been conducted. The pavement temperature forecasts, meteorological forecasts were all to be integrated into the snow and ice control decision process. The WSDOT contracted with The Matrix Management Group to evaluate the maintenance response to the new information, actual or potential cost savings with the information , and possible or real improvements in safety and service to the traveling public, and to suggest additional locations within the State which could benefit from improved weather information and/or operational changes in snow and ice control procedures which might result from the new information. The report presents a review of weather information system elements, provides an overview of the technologies in use by WSDOT, describes use of weather information by managers, and notes some problems. A detailed benefit-cost analysis was not conducted; a parallel effort was done for a nationwide project and complete structured cost data were not generated by the WSDOT for this analysis. However, national results are discussed in terms of the scale of WSDOT operations. The participation and results associated with the pilot program were found to be mixed. A need for training of managers and operational decision makers in the full concept and expectations of a road weather information system, and in the particular technologies described therein, is perhaps the central focus of this report. Although the evaluation noted limited success, national and international studies point to a greater potential for reducing costs and improving service for snow and ice control. Because of that potential, additional locations for installing sensorsare suggested.

Authors:
Boselly III,S. E.

Keywords:
accident rates

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Abstract:
This paper describes a novel approach to improving incident clearance when accidents require detailed investigation. This approach involves the use of computerized surveying equipment, called electronic total stations, for accident investigation. The use, advantages, and disadvantages of electronic total station survey equipment for expediting the investigation at serious traffic accidents are discussed. A comparison of three accident scenes where the coordinate method of accident investigation and total stations were used to measure the same incident showed that investigators can take over 70 percent more measurements per hour by using total stations. Furthermore, investigation with the total stations required only 46 percent of the time required with the coordinate method. A comparison of urban freeway accidents covering a one year period before total station were used to a year of total station use showed an average time savings of slightly over 51 minutes in incident scene clearance time. Accident drawings were aslo more accurate and could be prepared in less time.

Authors:
Jacobson,L. N., Legg,B., O'Brien,A.

Keywords:
accident rates

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Abstract:
This report overviews the experience of the Washington State Department of Transportation with asphalt pavements constructed with recycle scrap tire rubber. It documents the performance histories and construction costs for 21 projects constructed over a period of 15 years using both the wet and dry processes of adding the rubber to the asphalt mix.

Authors:
Anderson,K. W., Jackson,N. C.

Keywords:
accident rates

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Abstract:
A pavement tour of modified asphalt binder pavements was conducted in April and May of 1991 by staff from the Construction and Materials sections of the Washington State Department of Transportation. Each section visited is described and the tour participants\' comments regarding performance are summarized.

Authors:
Anderson,K. W.

Keywords:
accident rates

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Abstract:
This report presents a prototype of an Unstable Slope Management System (USMS) and corresponding user's guide. The USMS is a computer program that prioritizes unstable slopes. The system is composed of two parts: a database and priority programs. The database was developed using dBASE III Plus, Ashton-Tate. The priority programs were developed using the expert shell system CLIPS, a NASA developed language. The resulting USMS, at this point, is not an expert system; it is a management system. The USMS was developed with the aid of conversations with Washington State Department of Transportation personnel. In addition, a questionnaire was sent to WSDOT personnel concerned with unstable slope maintenance. From the conversations and responses to the questionnaire, the factors concerned with site importance were identified. Also, a method to determine the total importance was proposed. The USMS identifies factors that determine the importance of a failure site. These factors pertain to the cause of instability, cost of repair, use of road, and safety to motorists. Data pertaining to these factors is collected for each failure site and stored in the database. Priority ratings are assigned by the priority rating programs to the data for each site. The priority ratings are multiplied by a weight. The sum of the products represents the total priority. The total priority is a number from 0 to 100, 100 indicates the highest importance. The total priority represents the importance of the failure site based on the factors identified in the USMS. The total priority of a failure site is independent of all other failure sites.

Authors:
Ho,C. L., Norton,S. S.

Keywords:
accident rates

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Abstract:
A comprehensive view of the state-of-the-art in traffic noise abatement was conducted. Key literature was reviewed, and surveys conducted with the State DOT noise analysts, and local environment noise control programs, and vehicle manufacturers. Areas of interest included abatement strategies , effective vehicle noise control, land use compatibility programs, and programmatic and administrative issues

Authors:
Bowlby, W., O\'Grady, T., Patton, R.C., Herman, L.A.

Keywords:
accident rates

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Abstract:
This report examines major issues, concepts and methods of bus transit performance evaluation and suggests procedures and guidelines for internal and external monitoring in Washington State. In support of suggested procedures, data analysis on six years of operational and financial characteristics of Washington State systems, 1979-80 Section 15 data, and collected samples of small community/rural systems from other states was conducted. The major objective of the analysis was to test methodologies for developing and assessing transit \\\"peer groups\\\" relative to size and scale of operations, and prior to comparative within-group evaluation. The methodology entailed employing cluster analysis using up to 10 variables depicting service design and distribution. Two key variables were population and line miles. Problems were encountered in using Section 15 data. Due to its use of urban area, as opposed to service area population, clear distinctions of operating environments could not be determined. Thus, cluster groupings using Section 15 data were inconclusive. Cluster groupings using sample data for rural/small community systems (1980) and Washington State systems (1980) were satisfactory and following additional verification, a suggested \\\"peer group\\\" classification for Washington State was recommended. The seven group types ranged in size from a rural regional (<40,000 population) to metropolitan (>1,000,000 population). Values for 8 efficiency and effectiveness indicators were used to assess \\\"peer group\\\" trends in performance in Washington over a 5-year period (1976-80). Comparative evaluations of individual systems were not made. Despite only partial success in determining \\\"peer groups,\\\" the study does identify methods and procedures for assisting in external and internal performance evaluation.

Authors:
Kelley,W. J., Rutherford,G. S.

Keywords:
accident rates

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Abstract:
A five-year study was performed to compare conditions in the Pilchuck River before and after channel reconstruction associated with rerouting highway SR-2. The study focused on sediment particle-size analyses, benthic macroinvertebrates and fish. Substrates comparable le to control areas developedin all portions of the new channel within one year after construction. The available data on invertebrates and fish gave no indication of deterioration in diversity, quantity or size in the reconstructed channel. The report provides recommendations for further improvements in the design of stream channel changes should there be no alternative to their construction.

Authors:
Horner, R. R., Welch, E.B.

Keywords:
Alternative, benthic macroinvertabrates, accident rates, channel, condition, construction, control, data, design, deterioration, fish, highway, impact, impacts, improvement, Interim, reconstruction, rivers, sediments

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