Building or renovating infrastructure such as roads, bridges and dykes is not only complex from a technical and public procurement perspective, but also in terms of the range of environmental impacts which can occur throughout the project lifecycle.
RWS strives to ensure its procurement processes are sustainable and that they are achieving value for money, while procuring high quality outputs promoting sustainable practices and supporting a sustainable economy, whilst minimising resource use and environmental degradation, i.e. aiming at environmental impact reduction. Sufficiently targeted and ambitious policy measures are needed in order for procurers to stimulate the market to respond with superior, eco-innovative solutions.
RWS created DuboCalc, an environmental performance instrument, which in essence is a spreadsheet which allows one to calculate the material and energy use of a project. The advantage of DuboCalc is that it allows one to judge the sustainability of a given design in a relatively easily way. It also allows for a number of designs to be compared or considered on their own.
DuboCalc is designed for RWS employees and potential suppliers and is based on an LCA analysis. It consists of the Dubocalc software, a library, which is a reference document containing basic information and a project document, which contains detailed data. DuboCalc ensures that the winning bidder presents an eco-design, allowing the procurer to implement responsible purchasing.
Using advanced procurement mechanisms and facing the potential risks associated with using innovative and sustainable procurement techniques requires strong policy support at the national level and the establishment of specific, ambitious and well considered targets.
Contractors are given a year to achieve their CO2 mitigation goals allowing individual suppliers and the market as a whole to develop. One of the greatest benefits of using LCA software such as DuboCalc is that it offers the possibility to calculate design variants and alternatives, and as such, serves as an instructive tool for the contracting authority and contractor alike; enabling designers to calculate the environmental costs of a range of designs to arrive at an optimal solution implementing sustainability criteria.
Examples of green design or work processes undertaken in the Netherlands as part of procurement procedures using DuboCalc and the CO2 performance ladder include: recycled and reused materials, long life and low temperature asphalt, cement replacement in concrete, reduced concrete design of pillars and of bridges for pedestrians and cyclists, solar powered lighting and green electricity, low emission and energy efficient heavy duty vehicles and machinery, minimised transport of materials and fuel savings from driving courses for truck and dumper drivers. DuboCalc is estimated to be 6 on the GML scale.