RUIMTEVOORDEWAAL – ROOM FOR THE RIVER Alex Hill
This morning all 15 of the travelling eager beavers hopped on the doublewide eco-cruiser left behind our humble abode and took off like a flash to make our way to Nijmegen and see the Room for the River project on the River Rhine or in Dutch the River Waal (for you English speakers thats Vawl). After an amazing introduction to what the Dutch do with water when riverbanks are about to overflow (hint: they build taller dikes, move them around, and make more room for the channel), we geared up in thigh high galoshes, blaze orange vests, and a trusty hardhat to hit the dirt. Construction manager Rolf Pot and ProRail project manager Luuk van Hengstum guided us through the project site and described in detail what was happening at each location.
Everything around towered over us, underscoring the immense scale of the project, at 250 hectares it was like nothing I have experienced firsthand. Upon entering the soon to be riverbed, diesel smoke from the exhaust of trucks and tractors filled my lungs, a welcome relief from the fresh air I had been breathing all morning since smoking was not allowed anywhere on site. The ground plane changed with each step, as we felt squishy mud beneath our feet with one step and gravel roadbeds with the next. The belching backhoes effortlessly moved the glacial till; creating ever-larger piles of the silken material that surrounded the 12-meter deep foundation holes from which it was pulled. Each turn we took revealed handmade wood forms for footings and bent rebar for reinforcement; curving and sensuous, they were pieces of artwork in themselves. Being down in the site allowed everyone to witness the details of the colossal structures but it wasn’t until we rode over the Waalbrug (Waal Bridge) that we realized just how massive of an undertaking this project was.
I felt like a real Dutch boy as I rode my three-speed Cadillac cruiser over the Waalbrug where I witnessed a retrofit I had never heard of or seen. This newfangled piece of infrastructure employed the inventive reuse of the existing train bridge foundation to make way for a new multimodal crossing that now links Lent and Nijmegen via a fietssnelweg or bike freeway, rail corridor, and pedestrian paths. This bridge is just one of three existing bridges that required modification, and will contribute to a total of six bridges crossing the Waal in just three and a half kilometers.
For anyone that wants to learn more about the River Waal Project at Nijmegen/Lent or read about it’s 38 other brothers and sisters follow the link below:
Traveling around the country as a bezoeker (the dutch word for visitor that I learned today from the backs of the orange safety vests we wore throughout the site) the past 3 days have gone by in a flash. We are getting a crash course, amongst the speeding bikers, in the landscapes of the Netherlands and have covered a lot of ground, with some quick driving bus drivers, in a short amount of time. With little time to stop and look around at each area, except getting to pop out of the bus and stop for five minutes and then off to the next awesome spot for more of the same. Then yesterday we got a chance to get out of the hustle and bustle of a multi-stop tour and go to the De Hoge Veluwe to enjoy a national park. I was so excited to try to see everything in a few hours time flew by as fast as my bike wheels spun. Today we arrived at the massive Ruimte voor de Rivier (Room for the River) Nijmegen site, and learned that the project started in 2008 and has to be finished by December 31, 2015; this huge project is being created at an intense speed. The amazing speed at which life happens here, combined with my overall sense of limited time to enjoy everything, will take some getting used to, but sometimes its just best to dive in head first.
For centuries the Dutch have had to build higher and higher dams to keep up with the increasing amount of water and the increasing amount of created land. The Room for the River project works with, and accepts that there will be more and more water coming through the country and that they cannot keep building dikes higher so they are trying to create more space for the river, particularly for times there would be flooding. The site in Nijmegen is moving the existing dike 300 meters inland to make space for a new addition to the Waal River. The additional river will be 3.5 kilometers long, 200 meters wide and 9 meters deep. The movement and excavation of the ground for all the project elements (new riverbed, new dikes, water retention screens, bridges, and quay to name a few) there will be an estimated total of 5.2 million cubic meters of earth moved and 3 million cubic meters will be taken off site. All this work with planning and the extensive archaeology process will take place in 7 years. Typically it takes 3 years just for a new primary dike to be built and ready for use, but in the Nijmegen site they have used technology to speed up the centuries old tradition of dike building. The new dike is being made using a concrete core so there is little waiting time for the earth to settle. This eliminates the wait time for earth covering to settle but still utilizes layers of sand and clay to encapsulate the concrete core. The project takes the earth that is being excavated from under the bridges and shifts it to form the dike.
The speed of the Room for the Rivers project is quite rapid and is making use of new technologies to make the deadline. There was another visible technology being used in Nijmegen to control speed that caught my eye as we biked over the Waal, the wing dikes. Jutting out like little fingers into the river the wing dikes, an old technology, help with the sediment issues. The Waal River has been managed and channelized for hundreds of years and the sediment build up was an issue before the wing dikes were installed. The wing dikes stick partway out into the river on both sides creating a barrier, which slows down the water that gets behind the dike and allows the sediment to drop to the bottom. The wing dikes also speeds up the water (sort of like a hose that the stream gets faster when part of the nozzle is covered) that gets squeezed through the center, not allowing the sediment any time to settle and then continues down the river. While the wing dikes are effective the Waal in Nijmegen is currently dredged every 2-3 years. The part of the wing dikes that sparked my interest was the space created in the area between them. Where the sediment drops out over time small beaches are formed, creating both recreation opportunities and potential habitat. The habitat potential is limited by what Dutch law will allow in areas outside of dikes, no trees or items that can’t be removed in one days time to protect other infrastructure and prevent further damage during flooding.
With the sun getting lower the group of 18, all wearing blaze orange safety vests labeled in big black letters “bezoeker”, crossed the Waal River one final time on bike trying to take photos, make conversation, and not crash into any other commuters on the Fietssnelweg (bike highway attached to the Waalbrug rail bridge). Our last view was near the end of the crossing on the beaches below, on the soon to be island, occupied by just one couple, enjoying the afternoon sun with a moment of solitude in the middle of construction and the city.