Noise control in the compact city Evert de Ruiter Delft University of Technology, DIOC-DC0 ‘The ecological city’ & Adviesbureau Peutz & Associes B.V. P.O.box 696 2700 AR Zoetermeer The Netherlands E-mail: e.delnite~~~.citg.nrdzlft.nl 1. INTRODUCTION In the Delft Interfacultary Research Centre (DIOC) ‘The ecological city’ several disciplines of science are co-operating in defining, designing the contours of a city halfway this century, with a considerably smaller environmental utilisation space than present cities. The environmental impact consists of three parts: - utilisation of fossil energy and other exhaustible materials, - pollution of water, atmosphere and soil - loss of biodiversity Based on the formula of Ehrlich, Ehrlich and Speth’ reduction of the environmental impact by a factor 20 is the ultimate goal. While we are far away from this factor the exact value does not matter, nor does the method of calculation, at least we can use it as a metaphor for the necessity of a drastic change in environmental impact. 2. THE ECOLOGICAL CITY Of course the ecological city is a metaphor. Sustainable development can be realised in a newly built city ‘in the polder’ almost without restraints: new city plan, infrastructure, buildings etc. Noise control will require that industry will be quiet enough to fit in the neighbourhoods, or be situated far away. Transport will take place by underground or surface systems, but hardly with combustion engines or iron rails. The main sources of external noise will thus be eliminated: the ecological city can be a quiet city! In our existing cities however, such a degree of sustainability can not be reached, and maybe the amount of time needed for the transition to the ecological status is more than we think now. Therefor solutions for noise control remain important. Technologically speaking, 2421