Plant owner Ketchikan Public Utilities has requested the 12-month licence amendment to test new ramping rates against flow measurements on the 'flashy' Ketchikan Creek. It said that water level data were recorded upstream and downstream of the tailrace, and downloaded about once per month.
The revised licence conditions will measure ramping rates in terms of plant discharge per hour instead of the standard rise and fall in the river in the same period. Under the terms of the trial ramping rate regime, the utility proposed a range of seasonal discharge rates that would apply in relation to river levels.
FERC has agreed for the trial ramping regime to begin 1 April and expire 31 March 2008, and a report on the ramping rate results over the year is required by 1 July 2008.
