Flooding Scenario

FLOODING SCENARIO | Proposal

North eastern Hisingen is not the only area within Gothenburg that is at risk in a future extreme flooding scenario, this is something that the city of Gothenburg is well aware of (Göteborgs stad).

The city of Gothenburg is counting a 3,8 m sea-level rise as an extreme situation that could potentially occur around 2100, but is more likely to occur around 2150-2250 (Göteborgs stad).

This sea-level rise in combination with heavy rainfall creates a future situation in which current uses on North eastern Hisingen will not be able to function as they do today. This means that changes and adaptations will be necessary to keep the area usable in some way. Instead of trying to work against the water, the aim was early on set on working with the water. This would mean that the area might not be suitable for the current functions, since they will not function in a flooding scenario. Instead of aiming at preserving the current functions we decided on changing the character of the area and let it flood where it eventually will flood.

To do so, a large floodable green area/park is proposed along the river banks. To prevent rain-water run off from flooding current and future residential areas green corridors are proposed along the main water flows. These have the potential of both cleaning and slowing down the water, but also to highlight the qualities of water in your surroundings.

0 2 4 km

The geographical analysis tool SCALGO simulates a sea-level rise of 3,8 meter and heavy rain of 70mm. It shows that big parts of our area are at risk of being flooded.

Legend

Rivers/lakes/floodpoints Sea-level rise 3.8m

Main rain water flows

Need for extra protection

FLOODING SCENARIO | Sections

The conceptual sections shown in this spread seeks to explain what the proposed changes would mean for the area of north eastern Hisingen.

Today, as mentioned earlier, the layers of the area are clearly divided. This division is maybe particularly noticeable when it comes to the green structure, which in turn leads to a lack of possibilities for water infiltration in certain areas. In a extreme weather scenario, when current systems for handling rain water gets full, they risk overflowing. (Hoyer et al. 2011, 8)

To tackle this issue, large green areas are proposed both in the shape of a floodable park/green area but also by introducing green corridors along the main flows of rain water. By introducing these proposals the amount of green area in the area as a whole would increase and it would also “break the pattern” of hardened surfaces in certain areas.

The aim with these proposals is to achieve an area that is sensitive to extreme weather scenarios. The area should also be able to function to a large extent even when extreme weather scenarios occur. Finally, the proposed solutions aim at adding qualities to the area, both during normal situations and extreme weather scenarios.

The three scenarios show how the area is transforming in an extreme weather situation today and in our new proposal.

NATURE

NATURE RESIDENTIAL HIGHWAY INDUSTRY

RESIDENTIAL HIGHWAY INDUSTRY RIVER HIGHWAY NATURE Today normal

RIVER HIGHWAY NATURE Today extreme weather

NATURE RESIDENTIAL HIGHWAY MIXED-USED GREEN BUFFER-ZONE RIVER HIGHWAY NATURE Proposal extreme weather