Built areas and systems 261regionally significant agricultural land, moderate and compact growth
rather than major or dispersed growth is especially important.
(F) Llobregat West(general area around Gava-Sant Boi-Torrelles and perhaps
northward): residential commuters for the Barcelona metropolitan area.
(G) Lower Anoia area(general area around Piera and surrounding towns): a
promising area for a heavy-industry center and a trucking transporta-
tion center, strategically located near Barcelona and Igualada.Large adjacent green areas and the sea help provide a human scale (and a
linkage to the land) for the City of Barcelona as an extremely appealing urban
area (Acebillo and Folch2000). Urban models and experience emphasize that
growing cities do not have to expand contiguously into adjacent areas. Indeed,
most of the most appealing, livable, and successful cities maintain large open-
space green areas adjacent to the city to provide rich benefits to society.
Although Collserola and the Lower Llobregat floodplain and delta are far too
important for the future of the GBRegion to be used for development (Parc de
Collserola1997), the plan includes no major restriction on growth in the Valles
or the southwestern part of the Maresma (Forman 2004a). Assuming growth
of the Barcelona area will occur, densification of certain existing built areas,
along with limited residential expansion in the Llobregat West area, should
be considered. If industrial and transportation growth is to occur nearby, the
Lower Anoia area should be considered. Where hilly terrain is present, such as in
Llobregat West, exceptional environmental sensitivity and planning are required.
Some particularly beneficial forms for growth are identified, including the early
establishment of local integrated park systems, water-protection systems, and
infrastructure/public-transport systems.
Green-net areas
Where several growing towns or cities are in proximity, they could sim-
ply coalesce into a large urbanized area like a large inefficient non-city, or, if
adequate incentive and investment exists, could be formed into a major new
planned city near an existing major city. A third option, whereby each town
or city could grow in a limited manner and retain its distinctive identity, is
recommended here. To achieve this, agreen netof vegetation, farmland, or park-
land strips is established near municipality boundaries (Forman 2004a). Strips
can change, for example, from natural vegetation to parkland according to local
wishes, but must remain unbuilt green space. A minimum strip width seems
appropriate though adjacent municipalities could choose to have wider strips.
In this way each individual town can expand within its enclosed area, but not
merge with an adjacent town or lose its identity and distinctiveness.