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Report, 2016

Guidelines for outcome-based specifications in road mitigation

van der Grift, Edgar; Seiler, Andreas


As national road administrations increasingly make use of contract types in which the constructor not only builds but also designs the desired road or road modification, including mitigation measures for wildlife, a new set of specifications is needed in procurement. Procurement documents should no longer present detailed technical specifications but provide outcome-based specifications. Outcome-based specifications can be best defined as specifications based on what providers will achieve not what they will do. The reason that more and more governmental agencies shift to an outcome-based approach in procurement, is the aim to deliver more value within constrained budgets. The approach also means - which is often seen as an advantage - that risk management becomes more a responsibility of the contractor, while simultaneously the contractor gets more control and freedom in carrying out the project. Furthermore, it is assumed that an outcome-based approach provides a better breeding ground for innovations and increases cost-efficiency over the more traditional contracting models with prescribed products or services. Outcome-based specifications for the design and construction of road mitigation measures should have a clear link to the predefined objectives of the road project. In their turn, the objectives of a road project will be derived from - national and international - obligations that result from environmental and transport legislation and regulations as well as ambitions elaborated in environmental and transport strategies and policies. Environmental objectives ultimately refer to improving or maintaining population persistence and consequently biodiversity conservation. Transport objectives, in this respect, refer to improving road safety and avoiding impacts on the natural environment, including wildlife. The challenge in an outcome-based procurement approach is to translate these objectives to clear and measurable functions that can be provided by road mitigation measures. Here we develop guidelines for defining outcome-based specifications that can guide civil engineers to produce functional road mitigation measures and are in compliance with the current EU legal and policy frameworks. First, we identify what these frameworks mean for an outcome-based approach in the procurement of road mitigation projects and discuss the implications for defining sound outcome-based specifications. Second, we analyse the outcome-based specifications, currently used in road mitigation procurement in the Netherlands. We evaluate the extent in which these specifications reflect the requirements of the EU legal and policy frameworks and the potential to link clear and measurable performance indicators to the required outcomes. Third, we provide a set of practical guidelines for defining outcome-based specifications for the procurement of road mitigation measures. The use of these guidelines is illustrated by two practical examples. Finally, we discuss the potential benefits and risks of well-defined outcome-based specifications, based on the here presented guidelines, for policy makers, road agencies and other stakeholders, and provide recommendations on how to implement the use of outcome-based specifications in the procurement process. EU regulations and policies provide a variety of requirements and ambitions that are of concern for road projects and may help defining sound road mitigation outcomes. We identified fourteen indicators, all of which provide clues for defining outcome-based specifications to be used in road mitigation procurement. Besides these indicators, our review pointed out the importance of measurability of effects, both from activities that damage the environment and activities that aim to mitigate such damage, as well as the use of baseline conditions or reference standards that allow for quantitative evaluations. Using indicators that directly relate to regulations and policies, adopting a quantitative approach as well as incorporating clear baseline conditions or reference standards in defining outcome-based specifications, will inevitably improve the ability to judge whether performance requirements are being met or not. Although still in development, the outcome-based approach currently used in the Netherlands is an illustrative case that may help others to move from detailed technical prescriptions towards more generic descriptions of functions. The Dutch specifications clearly reflect some key requirements and ambitions of the EU legal and policy frameworks, although room for improvements exist as, e.g., use of indicators that relate to populations are lacking. Other improvements may be (i) to put more emphasis on the impacts that need to be mitigated, (ii) quantification of requirements and (iii) the use of baseline conditions or reference standards. Such improvements will inevitably lead to a higher potential to link the specifications to clear performance indicators. We identified eight guidelines for defining outcome-based specifications: Link the specifications directly to the goals for mitigation; Specify whether no-net-loss is the aim or not; Use the SMART-approach to develop clear and objective specifications; Make use of baseline conditions or reference standards; Link the specifications directly to the indicators used in regulations and policies; Link the specifications to multiple indicators whenever possible and relevant; Link the specifications to the road barrier to be mitigated and not to a single structure; Keep the use of technical specifications to a minimum. The use of outcome-based specifications, based on these guidelines, may have value for all stakeholders involved. First, they may better ensure that the overall objective - either related to wildlife conservation or road safety - is being met. Second, they may significantly increase our knowledge base, as such specifications will force all involved to gain more knowledge on what works and what not. Third, they may guarantee a strong link with, national and international, regulations and policies and better support political and/or societal discussions on the need and usefulness of road mitigation. And fourth, an outcome-based approach provides room for adaptive management. If road mitigation works, designed and constructed on the basis of the best available knowledge, appear not to be sufficient to reach the desired outcome, corrective measures can be taken. The use of outcome-based specifications may have certain disadvantages and risks if compared with the more traditional procurement approaches. First, they require better knowledge on mitigation measures and their effects than what we may have today. This implies that contractors may yet not be held fully responsible for a failure and/or the costs of mitigation works may increase. Second, costs may increase due to the need for studies in which baseline conditions or reference standards are assessed. Third, little is known about appropriate time-spans for evaluation studies, which may result in wasting resources or wrong conclusions on whether the measures are successful or not. Fourth, if not well regulated and safeguarded, knowledge on road mitigation effectiveness becomes an asset of private contractors and consequently may not be freely available to all stakeholders. And fifth, an outcome-based approach in road mitigation procurement requires a new juridical framework in which the responsibilities of both the road agency and contractors are clearly stretched-out. The shift in mindset needed for an outcome-based approach to work may take considerable time. This may result in a phase in which a ‘mixed approach’ is used in which functional specifications are complemented by an abundance of design specifications. The risk of such a mixed approach is that innovations will be slowed down and the strength of control mechanisms decreases. After all, if prescribed outcomes are not reached it will be difficult to point out the specific cause for the failure in the design. Is it the result of applying the prescribed design specifications or the result of decisions on the design made by the contractor? For example, if outcome-based specifications address population level end goals but the number of wildlife crossing structures and/or length of wildlife fences is prescribed by the road agency, the contractor may argue that goals are not met due to these prescriptions. Our recommendations for implementing the use of outcome-based specifications in the procurement of mitigation works are: (i) make sure that environmental authorities are closely involved in the procurement process in order to ensure that environmental objectives are adequately reflected in the contract; (ii) develop a generic set of functional specifications, which can be easily adapted to the situation and ambitions of the project at hand; (iii) use a similar language style in the writing of outcome-based specifications as compared to technical specifications; (iv) develop a clear set of performance indicators that accompany the outcome-based specifications; (v) contract an independent contractor for evaluating the road mitigation works on the basis of the provided performance indicators; (vi) develop a strategy for systematic assessments of baseline conditions and reference standards; (vii) develop an open access database on road mitigation evaluations, hence, future projects will be able to learn from previous ones; (viii) evaluate the use of outcome-based specifications in road mitigation procurement, as compared to the use of design specifications, and gather empirical evidence on the possible benefits and/or disadvantages of the approach. We further recommend to carefully test the guidelines presented here in practice, as well as a generic set of functional specifications that can be derived from them. If deemed appropriate after testing, modifications should be made in order to optimize their application in road mitigation projects throughout the EU.

Published in

Saferoad Technical reports
2016, number: 2
Publisher: CEDR (Conference of European Directors of Roads)

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