I have noted with interest your series on Jakarta, in particular the significant subsidence in the north of the city (Report, 24 November), for which a detailed study has been carried out by Dutch engineering experts. Obviously with most of Holland protected by the North Sea dykes, they have considerable experience to present to the Indonesian government for the proposed absolutely necessary wall across Jakarta Bay. Without it, very many hectares of priceless land and real estate, valued in the trillions of dollars, including the city's heritage, will be lost. While the project has officially started, the magnitude and related cost and other north coast interests have caused obfuscation in proceeding with development. As the wall is built it will then be necessary to construct freshwater lakes as a means of supplying developments in the sinking north. This subsidence is caused by many years of underground water abstraction, which currently and also certainly in the forthcoming years cannot be replaced by piped water supply from the south. There is no other alternative to the construction of the Great Garuda.
Prof Scott Younger
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