The Congost river,
of Mediterranean type, passes through Granollers (56,199 inhabitants)
with a total length of 6.7 km. Uncontrolled or wrongly planned interventions
had generated a high artficialization of the river basin environment
as well as the presence of the peripheral activities which had been
damaging the environment. This situation caused the cut of the links
with the rest of the urban public spaces aggravated by the inadequate
roads that have been affecting the mobility in the entire area.
The river basin
sanitation and environmental recovery project has been developed according
to the guidelines of the Environment Action Plan approved in 1999. The
interventions are organized around the river promenade, a corridor parallel
to the river to be extended in both directions. The type of each intervention
is planned differently according to the urban development level and
to the purpose of each area.
have permitted the functional recovery of the river ecosystem, the reduction
of the contamination with the consequent reduction of the sanitary risk,
the increase of the green spaces, the improvement of the roads, the
renovation of the urban areas next to the river and the integration
of the river basin as a peripheral urban environment. In this environment,
social, recreational and pedagogical activities can be developed, raising
the public awareness of this area and decreasing its tendency to marginalization.
that exceed the river basin were:
- The construction
of 1 ha. surface flow wetland, fed with the treated effluents of the
treatment wastewater plant of Granollers, as a tertiary treatment
system of sewages and a restoration measure for a degraded zone near
the river Congost. The system has become a key element in the natural
environments sorrounding the Congost river.
- The creation
of a water supply network for the water regenerated in the new pool.
This water will be used for the irrigation of the green areas, of
the controlled yards and for the city cleaning system. The network
will connect to an underground waters exploitation system that has
a 400 m² pond.
- The elaboration
of the Special Plan for the Protection of the Natural Heritage.
- The publication
of educational and informational materials about the environmental
values of the river basin and set up of a visiting program as well
as an environmental educational centre.
of the different administrations, companies with a recognized technical
level and certain members of the population guarantees the consensus
of the actions.
Some of the specific
results achieved are:
- Creation of 21
ha of urban and suburban fluvial parks and the planning of another
- Recovery of the
riversides (8 km) and labors of maintenance and preservation of the
riverbed (3.2 km)
- Recovery of 3.3
ha of contaminated soil by eliminating a source of the water pollution
- Tertiary treatment
of 2,50 m³/day of sewages, with a 85% reduction of the Biological
Oxygen Demand (BOD), and a 80% reduction of the Chemical Oxygen Demand
of an 8 km river promenade for pedestrians, sportsmen, cyclists. These
itineraries have been integrated in the existing network, making up
a total of 33.46 km, which will be extended to 44 km.
of a legal framework to include a regulation for preserving 131.85
ha area of natural interest (21% of the existing areas of natural
- Elimination of
the architectural barriers and increasing the quality of the public
areas (urban furniture, landscaping).
- Improvement of
the sanitation network in order to avoid the uncontrolled spillages
into the river.