Index Anillo Verde de Vitoria-Gasteiz

Improvement of the environmental quality and landscaping of the river Alegría

Brief description
The final section of the river Alegría has the function of an ecological corridor between the wetlands of Salburua and the river Zadorra, linking these two valuable ecosystems. Its development has also converted this section of the river into a place for walking and leisure activities between the Gamarra and Salburua areas.

Initial status
Before beginning work to recover and develop the final section of the river Alegría, it was a narrow, rectilinear waterway, the result of channelling work done in the seventies. Moreover, the bank nearest the city came within the boundaries of an industrial estate and was in a severe state of deterioration and neglect, with waste dumps, unauthorised vegetable gardens, etc.

The development process
Year started: 2001

Criteria:

• Guarantee the eological connection between the ecosystems of the river Zadorra and the wetlands of Salburua
• Restore the waterway and river bank environments
• Complete the structure of the Green Belt to the east by developing the river environment for public use

Actions undertaken:

The actions, which have affected a 11.5 hectare surface area with a length of 1.5 km, are included within a more extensive hydrological and environmental recovery project of the system comprising the wetlands of Salburua, the river Alegría and the river Zadorra.

Some of the problems that had to be dealt with included the frequent overflowing of the rivers Santo Tomás and Errekaleor in the eastern part of the city. Originally, the problem arose because, due to the growth of the city, these rivers became sewage collectors, thus favouring the rise of floodwaters in areas near the points where these rivers run underground. In order to avoid these problems, a project has been undertaken to divert the rivers Santo Tomás and Errekaleor, using the lakes of Salburua as separation pools and the basin of the river Alegría to divert the waters of the river Zadorra. Within this framework, the work on the river Alegría has consisted basically of widening the river in order to enable it to collect the new flows of diverted water.

This work, which has led to a major transformation of the final stretch of the river Alegría, has culminated in the creation of a new walkway along the river Alegría. The river Alegría walkway, that marks the edge of the town, has been designed in an attempt to combine and provide a transition between the urban nature of this environment and the more natural surroundings associated with the walkway along the river bank. In this way, the creation of two walkways at different heights, the choice of different materials according to their surroundings and the careful restoration of the planting have been used to resolve the transition between two very different environments along a narrow strip of land.

Current situation
Today, the river Alegría is a major ecological corridor between the river Zadorra and the wetlands of Salburua, allowing the transit of such representative species as the European mink, and provides an area for leisure pursuits and walking, connecting the areas of Gamarra and Salburua.

Future plans
The overall improvement of both banks of the river Zadorra and Alegría along this section represents a real challenge for efforts to enhance the environmental quality of this area. Thus, future actions will include replanting work to integrate and mark the boundary of one of the city’s industrial estates in a natural environment and improve the conditions of these rivers as biological corridors.

Likewise, the intention is to gradually resolve other problems such as the place where the pedestrian and bicycle route crosses the Vitoria-Bergara road.