Singapore's ideal population?

I haven't really thought about what population Singapore can sustainably support, but I believe its certainly much less than the whopping 6.5 million that our government is aiming to achieve, in the next 20 years no less :( Having 6.5 million people would turn Singapore into the world's third densest populated city with 9,293 people per sq km.

This is apparently good for boosting economic growth, which is the main reason why the government wants to do such a thing. Most Singaporeans don't support the policy, but their concerns are mainly about congestion, increased competition for jobs and places in schools, and the effect of increased numbers of immigrants on social cohesion. In fact, the debate about population often gets mixed up with the (sometimes rather xenophobic) debate about immigrants, as what with Singapore's declining birth rates, the government has to rely on increasing immigrant numbers to achieve their population target. Anyway, my point is that in all this, the issue of sustainability is almost never considered.

I think Singapore can support its current population of 4.5 million sustainably, if steps are taken to reduce consumption. Going by the I=PAT equation, which states that environmental impact (I) is the product of population (P), affluence (A) and technology (T), people in developed countries have greater environmental impact per capita than those in developing countries. Therefore, since Singapore has a high level of affluence we should stop trying to increase our population numbers because each person added is going to have relatively high environmental impact.

Si En