| dc.description.abstract | The heritage area Straen, also known as Gamle Stavanger is, due to heavy rain and climate change, in a position of stormwater flooding. The sewage system, that normally drains stormwater away from the streets, is old and cannot take on the increasing amounts of stormwater predicted in the future. This thesis explores how using local stormwater management (LSM) measures, sustainable drainage systems (SuDS) and nature-based solutions (NBS) can help mitigate the damaging effects of stormwater. The thesis also seeks to answer how this can be done without damaging the cultural-historical heritage. Through the use of literature studies, reference projects, visits to the site and GIS analysis, a proposal for a stormwater management plan using local measures is presented. To identify the suggested measures, an analysis of the area and how the area is affected by stormwater was done. Further, the thesis seeks knowledge from other projects that have addressed the same issues.
The stormwater’s effect on Straen is in close correlation to its catchment area encompassing parts of Trehusbyen, the largest connected wooden house area in Europe. The measures proposed in this area can be upscaled and implemented in several parts of Trehusbyen, due to similarities in urban layout. Thus, the proposal suggests measures for the upper districts of the catchment, as well as for Straen.
The planning for measures in these areas, Straen and Trehusbyen, had to be approached very differently, due to the availability of spaces fit for measures. To illustrate the effectiveness of the proposed measures, a 20-year 10-minute event with a climate factor of 40% is used. This equals an event of 17,5 mm in 10 minutes.
For Trehusbyen, the thesis proposes an implementation of a range of solutions that together are capable of handling the precipitation of a 20-year event. The measures are implemented in between housing, in gardens, driveways and entrances, and in the streets. These measures are effective and will not damage heritage values connected to Trehusbyen. But rather increase the resilience and make the areas more attractive.
The streets and neighbourhoods in Straen are narrowly built and require a different set of measures. Focusing on the creation, and dividing of flood paths, may lead to lower pressure on individual streets, thereby minimizing the risk of damage.
The measures proposed makes Straen capable of handling the increasing precipitation, and stormwater flooding. There are however implications when implementing big scale infiltration measures. A problem of water running on the bedrock, entering basements trough the foundations already exist in Straen. An increased infiltration may lead to this issue being more widespread. | |
