Allowing for the differences and complexities of real-world application environments, even the lowest improvement estimates of 60 percent yield tremendous savings.
The application for Dumfries and Galloway came after recent rain resulted in only a "very small improvement" in stocks at the Black Esk and Penwhirn reservoirs.
Researchers found a 20% improvement in progression to advanced AMD with the replacement, said Emily Chew, deputy director of epidemiology and clinical application for the National Eye Institute, a branch of the National Institutes of Health.