Norway has long made it a priority to deliver high-quality drinking water to its citizens. In fact, almost 100 percent of the Norwegian population has access to treated drinking water from waterworks that meet high-quality standards of the EU Water Framework Directive. But age, wear, and tear have taken a toll on the system.
A significant part of the Norwegian pipeline network has aged considerably. As a result, on average, 30 percent of the water leaks out before it reaches the consumer. But this waste of one of the most valuable resources on Earth – safe drinking water – is just one problem impacting the Norwegian water and sanitation systems.
Much like in many other parts of the world, some of Norway’s existing water and sanitation systems are not adapted to climate change, which is Increasing precipitation and flooding. These threats affect the quality of available surface water and present new challenges for water treatment.
Multiple areas in Norway have been impacted by this change in water quality, including Asker and Bærum. Thankfully the new Kattås Water Treatment Plant designed by Norconsult is helping bring safer drinking water to the people of these regions through innovative water sanitation practices. The Kattås Water Treatment Plant project was even named the Best Infrastructure Project from Autodesk during last year’s Autodesk University.
The GovDesignHub sat down with Christian Serck-Hanssen, Senior Project Manager at Norconsult, to learn more about the award-winning Kattås Water Treatment Plant, how this project impacted their community while maintaining sustainability, and the challenges they faced when designing a water treatment plant that would be excavated into a mountain.
GovDesignHub (GDH): Why is the Kattås Water Treatment Plant necessary? How will the development and construction of this plant improve the water treatment workflow and process for the people it serves? What benefits will the construction of this new plant deliver that the old facility could not deliver?
Christian Serck-Hanssen: Currently, water is pumped from Toverud into a tunnel up to Kattås, where the water is disinfected before being distributed through the pipeline network. However, climate change has resulted in higher temperatures and more intense rainfall, significantly reducing the surface raw water quality. This issue was especially visible in the color of the water and is due to natural organic material (NOM) levels. Because of this issue, the water being supplied to parts of Asker and Bærum was no longer in accordance with the requirements of the Drinking Water Directive in Norway.
These new processes will remove color and microorganisms while also adding alkalinity to the water.
To ensure safe and clean drinking water in the future and reduce the amount of color in the water, a new water treatment plant was designed with additional features that will use raw water from Holsfjorden. The mountain facility will consist of a chemical hall, filter hall, chlorination and UV disinfection, as well as a clean water reservoir.
These new processes will remove color and microorganisms while also adding alkalinity to the water.
GDH: Norconsult’s Kattås Water Treatment Plant claims it will “deliver safe and high-quality drinking water in a sustainable manner.” What features of the water plant increase sustainability?
Christian Serck-Hanssen: In order to ensure we kept sustainability in mind during this project, Norconsult followed the United Nation’s (UN) 17 Goals for Sustainable Development. Goal six, Clean Water and Sanitation, is the main objective for the water treatment plant. However, there are other UN goals for sustainable development that were incorporated into the design process.
These other goals included Goal 11, Sustainable Cities and Communities, by delivering solutions that make places inclusive, safe, resilient and sustainable. Goal 13, Climate Action, by calculating CO2 emissions and evaluating alternatives thoroughly. Goal 14, Life Below Water, by regularly registering aquatic life and restrictions for emissions to local residents. Goal 15, Life on Land, by registering local wildlife and restricting contractor activities during breeding season.
Even our construction activities for this water treatment plant utilized sustainable practices.
In addition to following these goals, we use sustainable practices during the water treatment process. Examples include using a ferrous coagulant that is a residual product from nearby titanium dioxide production, utilizing three compact media filters that require less volume and reduce concrete and rock excavation, recirculating water to reduce water loss, and using crushed marble to adjust pH levels.
Even our construction activities for this water treatment plant utilized sustainable practices.
One way Norconsult maintained sustainable construction included utilizing rock caverns to reduce land use while focusing on reducing rock excavation volume; the excavated rock was crushed to be reused locally. Other ways included using recycled concrete and restricting contractors to only use biodiesel or electric machines.
GDH: Are there any particular challenges that the geography or topography of the construction site created for the project? Does the mountainous terrain create any challenges for the plant’s design and construction?
Christian Serck-Hanssen: Norconsult faced quite a few geological and topological challenges due to the mountainous terrain of the Kattås Water Treatment Plant.
Complicated scenarios like these have made delivering clean water even more intriguing.
One example is that the geological and topological conditions had to be evaluated thoroughly to find a geometry that matched the adjacent existing infrastructure. This meant the hydraulic profile of the design had specific height requirements for the different steps of development of the water treatment plant.
The construction site area was also constrained due to the site being split by the rock to be excavated from the mountain, which led to unique challenges in treating the water that passes through the rocks and parking limitations.
Another geological challenge included the fact that not only did the new water treatment plant need to sit next to the existing water plant, but it is also located nearby a national park that includes Norway’s most common ski and hiking areas.
The challenges that were created by the mountainous terrain of the Kattås Water Treatment required our team to be creative and stay connected with the client. Complicated scenarios like these have made delivering clean water even more intriguing.
To learn more about Norconsult’s award-winning project, click HERE.
