Kryddstigen Industrial area,
Current land use
The area is an existing business zone where you find commerce, engineering, industry, etc. with a large proportion of impermeable surface. There are no current plans for land use changes in the area.
Gävle is a coastal city situated at the Gulf of Bothnia. The planning area, Kryddstigen, is situated about 2 kilometers outside the city centre. Kryddstigen is relatively flat and is located around 10 meters above the sea level. The soil in the area is mainly clay (glacial).
Site specific stormwater challenge
The planning site is located within the area of the city’s responsibility for stormwater management, which means that the city is responsible for receiving clean stormwater into the existing stormwater pipes up to a flow equivalent to a 10 years rainfall. Often, however, the pipes are undersized. Stormwater which cannot be received in the drainage system, must be handled locally by delay and/or infiltration.
The stormwater infrastructure from the planning site ends at the Hemlingby stream. The stream has problems with heavy loads of pollution and high flows. In previous investigations, problems with high flows and flooding have been observed at i.e. the Railway Museum and the Fjällbäcken trade and industrial area. To improve the flow situation, multiple storm water ponds have been built. The ponds restrict the flow in the stream at heavy rains. The nearest stormwater pond is situated upstream the planning area at Hemstaplan (Hemlingby church).
The stream is subject to environmental quality standards (EQS) of good status for surface and groundwater. EQS was determined in 2009 by the water authorities in accordance with the Water Ordinance (2004: 660) based on the EU Framework directive for water (2000/60 / EC). The goal was to achieve EQS in 2015. Eventually, the status may change for the worse and the EQS be extended (VISS, 2015). The problem areas include passage obstacles, eutrophication and metals (copper, zinc, arsenic and mercury).
Objectives from the city perspective
Gävle city is striving to become one of Sweden's best eco-municipalities and the work includes improving the stormwater management and reduce the impact on our recipients.
In Gävle city’s Water and Sewer policy, there are some items related to stormwater in built-up areas:
- The aim should be to use local delay of stormwater to maintain the natural water cycle, in order to reduce the risk of flooding.
- Polluted stormwater must be purified as close to the pollution source as possible and the volume of stormwater that is led away in pipes should be minimized.
Gävle city would like to get suggestions on how the planning site can manage the storm water, with solutions that work both from a flooding and purification point of view. Actions in this field will lead to a relief of the existing stormwater infrastructure and the recipient. The goal for the area is to cope with levels corresponding to a 100 years rainfall without damage to buildings and other infrastructure. Questions to handle can be how to technically build a local stormwater management system suitable for the area.
Location in watershed