A Visitors Centre has been opened in May 2007 that provides access to the new
delta wetlands created by the River Llobregat water reclamation project.
Advertising the new Llobregat Delta Visitors'
Centre
The delta of the river Llobregat lies to the south of Barcelona and covers
about 100 square kilometres. In spite of its very close proximity to the city,
it constitutes one of the most valuable natural areas of the region. The
wetlands are of international importance for wildlife and form a valuable
wintering ground for many migratory species of birds. The delta aquifer
is one of the most important fresh water resources of the Barcelona area,
forming an underground source with a capacity of 100 million cubic metres of
water. Numerous industries, agriculture and the population of the delta town of
Prat de Llobregat use its water, extracting it through wells. The fertile delta
farmland supports intensive agriculture to supply the local markets and as
protected Green Belt land, helps restrict urban
sprawl.
Since the 1960s, the delta and associated traditional land uses such as
market gardening have been under constant attack from Barcelona's urban and
industrial expansion. Catalonia’s most important logistics
and transportation infrastructures have become concentrated in the area: port,
airport, motorway network and railways. Less than 5% of the original wetlands
remain and in some municipalities half of the agricultural land has been lost in
the last decade.
By the end of the 1980s, the Llobregat was one of the most polluted and
degraded rivers in Western Europe. Over-exploitation of the underground water
had led to salinisation of the aquifer, with 30% now being
unusable. The most recent city projects that affect the area are summarised in
the Plan for the Llobregat Delta below. Future threats include the impact of rising sea
levels.
Plan
for the Llobregat Delta
The Plan for the Llobregat Delta consists
of a set of coordinated projects and investments in transportation, logistics
and environmental infrastructures to be carried out until approximately 2010.
This will enable Barcelona to become one of the gateways of Europe as well as a
bridge to Latin America and the Mediterranean. Total surface area
1,000 ha Main projects
The Plan includes the following projects:
1. Diversion of the Llobregat river and environmental improvements.
2. Expansion of the Port and creation of a Logistics Activities Zone.
3. Expansion of the Airport.
4. Road and railway infrastructures
Since 1991 and after the European directive on urban wastewater, a
comprehensive programme of water treatment plants has been implemented along the
river and the situation has improved dramatically. For example, the beach at
Prat de Llobregat, near the mouth of the river, was a principal pollution black
spot along the Catalan coast. It has been open now for bathing since 2002.
The objective of the new water reclamation project is to maintain the
ecological flow of the Llobregat river which runs through Barcelona by partly
closing its access to the sea. The reclaimed water that was previously lost to
the sea is pumped upstream to increase the natural flow of the river as well as
to provide capacity for agricultural and golf irrigation and the recharge of
wetlands. The reclaimed water receives additional reverse
osmosis treatment for aquifer recharge to control
seawater incursion and salinisation.
This is an innovative water scarcity solution that is applicable to all large
coastal cities. The project not only preserves the habitat along the length of
the river and the marshlands at its delta, but also supports the tourism
business by helping Barcelona to maintain its reputation as one of the most
beautiful cities in Europe. In addition, the scheme has low carbon impact as the
process works by gravity. It is one of the largest wastewater reclamation
projects in the world and the first major tertiary water treatment facility
(eliminating nitrogen and phosphorus nutrients) that saves approximately 80% of
the energy used in conventional plants.
The water purifier has a capacity of 50 million cubic metres of water per year
and cost 260 million euros, with an 85% contribution from the EU Cohesion fund.
“It is the largest investment in cleaning and purification of water in Spain”,
said the Environment minister, Elvira Rodriguez, during the opening of the
plant.
River Llobregat water reclamation scheme
New wetlands created at the river mouth
A submerged breakwater at the river's mouth has helped create
a wide artificial channel
Diversion of the river to create the new channel
River Llobregat immediately upstream of the managed channel
A green belt is undeveloped or agricultural land surrounding an
urban area where development is heavily restricted by law. The purpose is to
protect natural environments and wildlife, improve air quality, ensure that
urban dwellers have access to countryside and protect the character of rural
communities which might otherwise be absorbed by expanding suburbs. Barcelona's Green Belt
Logistics
Logistics is the management and control of the flow of goods
and services from the source of production to the market. It involves knowledge,
communication, transport and warehousing.
Reverse Osmosis
Reverse Osmosis involves forcing water through a porous
semi-permeable membrane. The small pores of the membrane block salt and other
natural minerals, which generally have larger molecules than water. These pores
also block bacteria. Thus, reverse osmosis is very effective at desalinating
water and providing mineral-free, clean water.
Salinisation of the Aquifer
An aquifer is an underground layer of permeable rock from which
water can be extracted using a well. Water in an aquifer is called ground water.
The Llobregat delta aquifer has a layer of fresh water near the surface and
denser salt water under the fresh water. Salt water penetrates the aquifer by
moving in from the sea. The thickness of fresh water on top of the salt water is
normally about 40 metres of fresh water for every metre of salt water above sea
level. Too much ground water in the delta has been pumped from wells for
agriculture, domestic use and industry, leading to salt water intruding into the
upper layers of the aquifer causing contamination of freshwater supplies.
Urban Sprawl
The unplanned and uncontrolled growth of urban areas into the
surrounding countryside. Barcelona's
Urban Sprawl
