METHODS: This study enumerated the abundance of E. coli in the water and sediment at five urban lakes in the Kuala Lumpur-Petaling Jaya area, state of Selangor, Malaysia. We developed a novel method for measuring habitat transition rate of sediment E. coli to the water column, and evaluated the effects of habitat transition on E. coli abundance in the water column after accounting for its decay in the water column.

RESULTS: The abundance of E. coli in the sediment ranged from below detection to 12,000 cfu g-1, and was about one order higher than in the water column (1 to 2,300 cfu mL-1). The habitat transition rates ranged from 0.03 to 0.41 h-1. In contrast, the E. coli decay rates ranged from 0.02 to 0.16 h-1. In most cases (>80%), the habitat transition rates were higher than the decay rates in our study.