Large-scale bridge renovation for water authority Noorderzijlvest: a circular approach
Water authority Noorderzijlvest wanted a better insight into the condition of the bridges under their management, which consists of up to 80 bridges. These bridges are reaching the end of their lifespan, posing a considerable challenge. A thorough analysis, using the relevant NEN standards, provided insight into the maintenance condition of the bridges. Where a bridge did not meet the NEN standard, further investigation was done. The further investigation showed that a number of bridges had safety issues. This resulted in a targeted four-year renovation programme, in which 15 bridges were eventually renovated in clusters of around four at a time.
Implementation of the assignment
- Client: Noorderzijlvest water authority
- Projects: Bridge maintenance programme, in which 15 bridges were replaced
- Procedure: Framework agreement with 1 party, after which one or more bridges were developed in construction teams.
- Award: 2019
Circularity was a central theme in this renovation, as the Noorderzijlvest Water Authority strives for sustainability and reducing its ecological footprint. This involved applying the R-ladder, a model for circular strategies. The circular measures implemented include the use of modular bridge decks and pre-hanging bridge deck upstands that can be easily replaced and reused. In addition, steel girders, railings, wooden sheet piling, retaining walls and concrete were reused instead of poured wherever possible. Several efforts were also made to use life-extending design to preserve bridge abutments by relieving them of traffic loads.
Three factors that made this project a success
Programmatic approach to renovations
By using NEN standards (NEN- 2767, 8701 ), which determined the current condition of the bridges by means of a condition assessment, plus extensive investigations, Water Authority Noorderzijlvest got a clear picture of the current condition of their existing bridge stock. This insight into the condition of the bridges under their management is crucial for a targeted approach to renovations. By providing insight into the state of maintenance, the bridges can be more easily transferred to another asset management company in the future.
Programme approach for multi-year planning
The multi-year renovation of several bridges simultaneously allowed for better planning and the achievement of circular goals. This programme-based approach offered more advantages than tackling a bridge renovation individually.
Flexibility and quality in the procurement strategy
There was a deliberate departure from the standard procurement procedure. The framework agreement focused on flexibility and quality. This allowed the market to be involved at an early stage. It also gave room for innovative solutions from contractors. This approach ensured the works were carried out to a higher standard and enabled the Noorderzijlvest Water Authority to respond quickly to unforeseen challenges.
Tips for similar projects
Make use of existing information
Make use of available knowledge and information on circularity and procurement. There is already a lot known about how circularity can be integrated on projects. It is not necessary to reinvent the wheel yourself.
Open attitude of the client
Ensure open and clear communication with the market. This helps to manage expectations and achieve the best results.
Take your time
Circular procurement takes time. Make sure sufficient time is scheduled to achieve circular goals and involve the market from the start of the design stage.
Be realistic
Be practical and realistic in your approach. In doing so, carefully consider how much time and resources you are investing and what this will ultimately yield.
