Figure 2 : Example of macro-scale urban that are not being collectively assessed
separately , such as housing , industry , forestry , infrastructures , etc . [ 18 ] The assessment is performed on-site , and mostly before and during the construction stage . However , the environmental impact of new construction often has a prolonged effect that propagates to the surrounding regions . A typical example is the ongoing continuous construction of multiple highrise buildings surrounding existing landed housing areas as shown in Figure 2 .
The environmental impact might not be severe in the on-going projects but it is collectively felt by the existing township that is encircled by these projects . The noise pollution , air quality , airflow , and availability of sunlight in the existing housing areas are compromised , aggravating health and living conditions . Therefore , the environmental assessment involving the influence and interaction between different activities has to be included , especially in rapidly sprawling urban centres .
These are near ideal conditions but it does not mean that they are impossible to achieve . There is an internationally renowned green township in Malaysia , known as Putrajaya . It has embraced the Garden City design by reserving 38 % of the total land area for recreational parks , gardens , water
bodies and open space , limiting the composition of urbanised land cover [ 19 , 20 ].
Malaysian Urban Indicators Network ( MURNInets ), introduced by the Ministry of Federal Department of Town and Country Planning and the Ministry of Housing and Local Government , allows the sustainability assessment of urban areas up to the local district level , using 39 indicators that are branched out from 20 themes , six dimensions and five strategies [ 21 ]. However , planners are given the flexibility to pick the indicators to use and reject , creating a non-uniform rating among the same level of localities [ 22 ]. The assessment criteria become suspect when the ratings are mostly above 80 % ( sustainable ) for the evaluated local authorities . Due to unfamiliarity with the importance of sustainability indicators , MURNInets is little known and poorly accepted [ 23 ].
On the Meso-Scale
On the meso-scale , the geological , climate and weather conditions , such as precipitation , ventilation rate and water catchment , have to be taken into account . For example , the Jakarta conurbation is experiencing rising sea levels and
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