N31 Dual Carriageway

Drachten, The Netherlands
19 Years of successful partnership resulting in a smooth handback to our client, Rijkswaterstaat
8th December 2003 Financial Close
2004 - 2008 Construction Period
15 years Concession Period
December 2022 Handback
N31 Dual carriageway

The background

The N31 Dual Carriageway located between Dutch towns, Drachten and Leeuwarden, is Invesis’ second PPP project to reach the end of its contract and be returned to Rijkswaterstaat. After 19 years of successful partnership, the asset was returned on 13 December 2022 at the end of its concession period in immaculate condition.  

Re-construction of the N31 from a single section of road to a dual carriageway was necessary to improve traffic flow and road safety. Through a design, build, finance and maintenance (DBFM) arrangement, Rijkswaterstaat commissioned the construction of an aqueduct at the Hempenser Wielen and the replacement of the existing Fonejachtbrug by two bridges and doubling of the total route to 2×2 lanes over 13 km.  

In 2003, Rijkswaterstaat entered a PPP agreement with consortium Waldwei.com b.v, comprising Invesis and Dura Vermeer. As a result of the PPP model and the strong relationships formed over the past 19 years, the N31 is now a high-quality dual carriageway that alleviates congestion, has boosted the economy and reduced road traffic accidents.  



Capital Value



Invesis and Dura Vermeer


Waldwei.com b.v

Engineering, Procurement and Construction (EPC)

BAM Infra, Ballast Nedam & Dura Vermeer

Operations and Maintenance (O&M)

BAM Infra, Ballast Nedam, Dura Vermeer

Business value

For fifteen years, the consortium took care of the management and maintenance of the 22 km long road. Through fostering open communication and collaboration, any issues were addressed and rectified quickly to minimise disruption. 

Rijkswaterstaat was handed back the N31 in a condition which met the terms of the contract signed over 19 years ago. Due to thorough preliminary work carried out by our team of experts, the project was transferred back to the client on time. 


Key features

By using the PPP contract approach and partnering with the Waldwei.com b.v consortium, the project; 

  • during construction, remained operational with the works being completed four months ahead of schedule 
  • procurement through the DBFM contract, delivered cost savings of 31% in comparison to traditional procurement methods at the time 
  • was handed back to Rijkswaterstaat on time in great condition