What were the concerns that influenced town planning in the nineteenth century?

After the Revolt of 1857, the British nurtured various concerns and worries regarding town-planning which is evident from the following points:

Constant Fear of Rebellion : Having faced the Revolt of 1857, the whitemen in India had a constant fear of rebellion from Indians. So they wanted to live in more secure and segregated enclaves. To ensure their defence, they wanted to live away from the native people from whom they faced the threat of rebellion. So, they cleared many agricultural fields and pasture land and set up urban spaces called the Civil Lines. The Englishmen lived in these Civil Lines. They also set up cantonment areas for the stationing of the armed forces.

Development of White Towns : The British were also concerned about epidemics like cholera and plague which often spread in India, killing thousands of people. So they demarcated both Black and White areas. The black areas symbolised only chaos and anarchy. They stood for filth and disease. The British always feared that disease would spread from the Black to the White areas. So they developed White Towns for themselves. These towns signified hygiene and cleanliness. The British took stringent administrative measures to ensure sanitation of these areas. They also regulated the building activity. They also made arrangements for the underground piped water supply. They cared a lot for sewerage and drainage systems. In fact, they kept an utmost sanitary vigilance.