Development Aspects Impressum Editors

Integrating natural and built infrastructure approaches

Often, natural infrastructure offers better solutions than built or physical infra- structure alternatives, but not always. Sometimes, after thorough assessment, physical infrastructure can be determined as the best option. But most often, natural infrastructure will exist and need to be managed alongside existing or developing physical infrastructure approaches (Box 6). Policy and management approaches need to shift from favouring one approach or another to identifying and implementing integrated solutions that deliver the most sustainable and cost- effective solution overall. In this assessment, it is critical that all the benefits that are delivered by all options, including those beyond just “water management”, are identified, properly valued and compared impartially (Krchnak and others, 2011).

Box 6: Maximizing physical infrastructure benefits through restoring natural infrastructure in the Itaipu watershed, Parana River basin, Brazil

The important Itaipu Dam in Brazil is one of the largest dams in existence. The Itai-

pu watershed includes deep red ferralsols, with good fertility potential, located in a

humid subtropical climate characterized by hot, humid summers and mild winters.

There is high agricultural productivity, but violent rain storms lead to high erosion and

flows of sediments and nutrients into Itaipu Lake. Eutrophication and sedimentation

reduce the productivity of the dam. This is being addressed through the community-

based “Cultivando Água Boa” (Cultivating Good Water) programme, supported by

the Brazilian Federation of No Till Farmers Associations (FEBRAPDP), supported by

Itaipu Binacional (Itaipu Dam Enterprise). Success is being achieved by simply trans-

forming agriculture from tillage-based to no-till conservation agriculture (see Box

4). When the dam was built, its estimated working life was 60 years, but by manag-

ing soils as natural water infrastructure the life expectancy of the dam has increased

tenfold, and farmers benefit through improved crop productivity and sustainability.

Source: Amir Kassam ([e-mail]), Ivo Mello ([e-mail]), Herbert Bartz, Tom God- dard ([e-mail]), Theordore Freidrich, Francois Laurent ([e-mail]), Norman T. Uphoff (Planet Under Pressure Conference, London, United Kingdom, 26–29 March 2012).

5.