Existing plans

In today’s plans, flooding is a topic which is discussed to a highly varying degree. Some plans for Nyhavna mention flooding several times and present measures for how to reduce the risk for flooding. In other plans, however, the word flood is not mentioned at all.

Municipal sub-plan

A starting point for the planning of Nyhavna was the municipal sub-plan (kommunedelplan in Norwegian) which was approved in 2016. The municipal sub-plan emphasizes that Nyhavna should be a robust mixed-use neighborhood with high density (Trondheim kommune, 2016). The plan also highlights the need for sustainable design solutions, for example by having a variety of green spaces and good accessibility for pedestrians and bicyclists. The plan map (fig 8) shows that the areas closest to the sea (H1, G4 and F5) are not going to be used for residential purposes. However, the rest of the area will see relatively high-density apartment buildings, as well as some small parks. The promenade along Nidelva will be extended to cover the entire western edge of the area, thus also creating a “bluegreen” buffer between the sea and the residential parts of Nyhavna. The municipal sub-plan, however, does not discuss the flood danger in Nyhavna at all. It is discussed further in the so-called “quality program” (kvalitetsprogram in Norwegian) which acts as a supplement for the 2016 sub-plan. The quality program was approved in 2022.

Supplementary quality program

The quality program discusses the dangers which Nyhavna could be facing in the upcoming decades. Here, flooding due to sea-level rise is reviewed and discussed more in detail. According to the qual- ity program, no planned buildings should be affected even during events with extraordinarily high water levels during the 21st century. However, by 2150, the water can reach the ground floors in buildings located closest to the seaside (Trondheim kommune, 2022). Thus, it can be discussed whether the blue-green buffer should be extended further inland to protect the future inhabitants of Nyhavna from flooding. As seen in figure 12 the western part of Nyhavna, including the riverside along Nidelva will be prone to flooding in the future.

Parallel project groups

The municipality has received feedback on their plans from the so-called parallel project groups which consist of experts with different professional backgrounds. The project groups criticize the municipality for the lack of comprehensive plans for the blue-green structures, which can also lead to a higher flood risk. In addition, they propose a floodgate to protect the central parts of Nyhavna from future water level rise (Trondheim kommune, 2020).

Implementation of plans

The implementation of the plans discussed above has begun, as architectural contests have been taking place. In February 2023, the architect office Cobe won the architectural contest for the western side of Nyhavna (Nyhavna utvikling AS, 2023). Pictures and maps (fig 9 and 10) that are available online show that revetments are used as a coastal protection measure on the western side along the planned promenade. There is however a high level of uncertainty connected to whether the illustrations used in the contest will be implemented directly in reality.