by David Stearns, P. Eng. and Jaime Boan, P. Eng., Stanley Consulting Group
Last Month the "early years" and the "production years" were reviewed.

The "High Tech" Years
The 1980’s provided the Design Engineer with the personal computer (PC). The Computer Priests could now be bypassed and the key databases maintained locally. Personal Computer applications became the focus of the Design Engineer. It was now possible to adjust grades to the millimetre and balance earthwork to the last cubic meter.
So-called intelligence was incorporated into the design systems with user-defined standards and intelligent templates. It was now possible to gain insight to the volumes of information provided by the speciality fields. The "Specialists" also became more sophisticated in data management and were able to provide better information in a graphical form.

The 1980’s also involved development of Geographic Information Systems in some of the larger agencies. This allowed for comparison and compilation of data in new ways. Real time monitoring (or close to it) became a possibility with the introduction of PCs in the field.

Design refinements were relatively easy with a computer-based process instead of the laborious and frustrating manual exercise. However, this meant that the road designer was now expected to generate large numbers of options and the term "diminishing returns" took on new meanings. PCs also allowed for greater integration of design and production. The Design Engineer was now faced with new issues such as layering and line types. It seemed that every road authority was developing their own unique drawing standards. This still continues today.

After several updates, the Roads and Transportation Association of Canada (now TAC) published the Manual of Geometric Design Standards for Canadian Roads, 1986 Metric Version.

The 1980’s brought significant downsizing of agencies due to dwindling transportation budgets. The resources available to the Design Engineer were severely limited compared to previous years even though there was increased emphasis on public demands, user safety, environmental constraints, social impacts, stakeholder liaison and on improved geometric design practice and traffic engineering. This resulted in a greater dependence on the Personal Computer and the insight of experienced Technologists.

The Road Design Engineer was faced with greater design constraints and demands for more refined designs than ever experienced in the past. New technologies involving transit, the vehicle, the driver, the road, new safety features, information systems, and materials were developed. The Road Designer’s role became intensely focused on optimization and incorporation of available technologies; and a "balancing act" between competing interests, limited budgets, and growing demands. The Road Designer began to dig out of the pile of paper and focus greater attention on the impact of the design to user safety, the environment, and society as a whole.

The 1980’s brought other changes. PC’s allowed the Road Designers to improve the analysis of information related to planning, construction and maintenance; thereby, improving the response to long term operational needs. New emphasis was placed on transportation economics and traffic modelling. The Construction Engineer began to recognize the complexities built into design decisions and thus the Design Engineer was more involved in changes contemplated during construction.

The 1980’s involved many discussions between Road Design engineers across Western Canada regarding the design trade-offs facing them. Each road authority would ultimately establish its own policies. Trade-offs often included safety, operational efficiency, design life, the environment, and the impact to property owners and society in general.

For example, a classic trade-off seen in British Columbia is the extensive use of concrete roadside barrier. Rather than expending large sums of money to procure property and cause major impacts to existing development to facilitate wide clear zones, concrete roadside barrier was incorporated into the designs.

Concrete roadside barrier is an obstacle and can be hit by an errant vehicle. This is a trade-off to safety. Another example of a safety trade-off is the clearing of sight triangles at controlled intersections. It is common practice on the prairies to clear sight triangles at all rural intersections. The idea being drivers on the major road should be able to confirm that drivers on the minor road are respecting the stop sign. However, trade-offs are made when the cost becomes excessive, and ultimately total reliance on drivers obeying the stop sign is often required.

The 1990’s have been an extension of the 1980’s; however, the array of design tools has exceeded the Design Engineer’s capabilities. The Design Engineer’s role has evolved into a coordinator of highly specialized professionals. For example, it was not unusual during the latter 1980’s for the Design Engineer to be familiar with almost all of the available engineering software. A single road designer can no longer achieve this.

The need for "applications specialists" has grown. Total station survey, digital terrain modelling, digital aerial photography, intelligent design templates, graphical design systems, rendering, modelling, driver simulation, fuzzy logic, are a few examples of technical innovations requiring the knowledge of applications specialists. Design Teams for large sized projects commonly include Road Design Engineers, Geotechnical Engineers, Environmental Engineers, Traffic Engineers, Hydrologists, Economists, Structural Engineers, Acoustics Engineers, Landscaping Engineers, Communications Specialists, Graphics specialists, Estimators, and CAD Specialists.

The boundaries between municipal and rural road designers are decreasing. This may be best evidenced by the development of TAC’s 1995 Urban Supplement to the Geometric Design Guide for Canadian Roads. Also there is currently a committee which is combining the road design guidelines into one manual. This is not a surprising trend because the basic components still involve the road, the driver, and the vehicle. Only the application of design elements varies.

The Design Engineer has continued to be the person responsible for coordinating, compiling, assessing, and incorporating the input received from specialists. The Road Design Engineer also continues to remain responsible for determining the trade-offs and using judgement in forming the final design. It should be noted that trade-offs are also necessary as a result of new information gained in the field during construction. The Construction Engineer has a significant role in evaluating trade-offs with the designer.

Evolving Concerns
The "balancing act" has grown into a sophisticated design process. The process has, in some instances, become too complex and too costly relative to the size of the projects. Creative methods of streamlining the process have emerged such as design/build contracts. How new is this? If you recall, this article began by describing how the Design/Construction Engineer exercised considerable judgement in the field and worked closely with the contractor’s Superintendent to resolve problems in the field.
We also see severe budget constraints requiring a review of basic design practices, sometimes coined Value Engineering. Or is this a renewed emphasis on allowing the Road Designers to collaborate with others and exercise judgement when applying design elements to a specific situation within the context of a severe budget constraint. The budget is becoming the dominant design constraint.

The 1990’s have also allowed the voice of special interest groups with deep pockets to skew some aspects of Design Engineering. For example, developers have persuaded decision-makers (political officials) to allow deviations from the recommendations put forward by engineering staff. It seems that the argument in favour of, or, against a particular planning or design issue often centres on safety. Political officials will rarely contradict the Professional Engineer if a deviation is deemed to be unsafe. However, "safe" is a relative term and must be considered within the context of a comparison to other situations (i.e. what constitutes an unsafe situation?). The Design Engineer often is faced with a losing battle. The decision to scrap the entire project due to a specific design issue has become a reality. This is especially true in smaller municipal centres where the Council is micro managing.

Some agencies including municipal governments are beginning to fill the void left behind by Provincial Road authorities. For example, budget cuts and reduction in staff have essentially dismantled the BC Ministry of Transportation and Highways safety section. The Insurance Corporation of British Columbia (ICBC) has filled the gap by establishing its own road safety improvement program. This has proven to be a very successful initiative; however, the research, awareness, and implementation of road improvements focuses on achieving a positive net return to ICBC.

This focus does not recognize other transportation system priorities and has the potential to artificially skew the allocation of funding when optimizing expenditures for social good - i.e., this is great for ICBC but perhaps not the best for society based on a multiple accounts analysis.

Some municipal governments are beginning to explore the development of inter-regional travel toll roads as a means of improving development opportunities for their communities. This may prove to be a fruitful endeavour for a municipality; however, this may skew the development of road infrastructure toward lower priorities in the Province. The bottom line is that as the senior government funding dries up, other special interest groups begin to move in (e.g., private toll roads). This trend does not recognize the best allocation of funds for social good. The Road Designer along with the Planner is now faced with a moving target when setting up programming for design projects. A growing concern by some Road Designers is the trend towards so-called independent audits of designs. This concern is especially applicable to post construction audits. Post construction audits by the Road Designers and Construction Engineers have been conducted for at least twenty-five years. Often the Design Engineer, the Construction Engineer, and the Maintenance Engineer would jointly audit a project upon its completion. Emphasis was placed on learning from design deficiencies or changes required in the field. It was not unusual to conduct "travelling road shows" with all of the Resident Engineering staff as a training measure. It is the Authors’ belief that independent audits of designs are not credible unless they account for all of the design issues and necessary trade-offs considered. Trade-offs are a necessary part of design and unless adequately understood by the Auditor, the design review may be biased.

Given the experience of the past, safety reviews are nothing more than design reviews with a specific focus. Similar audits can be done for social impact, environmental impact, drainage, operational efficiency and so on. It will be a great loss to the engineering community if the benefits of training Design Engineers and Construction Engineers through design audits or post construction audits are lost. The tail should not be allowed to wag the dog.

Summation
The role of the Professional Road Design Engineer continues to grow in complexity and becomes more challenging with each passing year. The support of Specialists and the involvement of experienced Professional Engineers and Technologists is a key component for the success of road design. The Road Designer’s future appears to be oriented to that of a conductor and is often referred to as the Design Project Manager. The ultimate responsibility will remain with the Road Designer (the person who seals and signs the design), however, design team Specialists will likely be required to assume a greater responsibility for their input.

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