The Women and Children's Crisis Centre in Tonga says people living in low-lying, densely populated parts of Nuku'alofa are faced with water supply and waste disposal problems every day.
A Centre spokesperson, Lesila Toia, welcomes a 12 and a half million US dollars grant to help address infrastructure issues.
The Asian Development Bank, along with the Australian government aid agency, AusAID, is providing the grant.
Tonga is contributing another two million.
"The water is running at a slow pace often in the morning when people are hurrying up to work and school. Not only that but with solid waste, sometimes [residents] burn their rubbish at their homes but with this infrastructure improvement I think it will help."
Lesila Toia says she hopes the infrastructure development will address the fact that some of the poorer residents of the capital cannot afford to or do not know how to dispose of their solid waste safely.