Weathermatic SL1600 Water System Controller Bundle. Weathermatic is the undisputed leader in smart irrigation controllers and they've built their entire water management business based around the Smartline SL1600. If you are interested in using "smart" irrigation technologies to reduce your water bill by as much as 50% then Smartline is the right choice. Weathermatic products are designed with efficiency in mind. The typical Â½-acre commercial property uses about one million gallons of landscape water per year.