The site of Lake Alexander was originally an area of low-lying coastal marsh. It is now the main element that sets East Point Reserve apart from other attractive picnic areas in Darwin. Lake Alexander has a maximum depth of 2.8 metres and a water quality similar to other naturally occurring swimming areas. Its seawater is drawn from nearby Fannie Bay.
The 3.5 hectare lake was officially opened in July 1991, providing a body of water that is safe for recreational activities throughout the year. It is dangerous to swim in our unprotected and open seawater between October and May. This is why Lake Alexander is so popular during the summer months.