let me first explain that the sod in the picture was only temporary for the opening party in march (our leed rater freaked when she saw the grass at the party since sod is obviously a big no no for leed). the permanent grass we're going to use for the grasspave driveway is a special drought tolerant fescue blend that only comes in seed so it wouldn't grow fast enough for the party.
after the party we have only watered the sod as much as the permanent drought tolerant landscaping. the picture below shows how each plant has survived over the last two months. the drought tolerant planting has thrived with water about every three weeks while the sod is 95% dead. about 1/3" of national water use, about 7.8 billion gallons annually, goes to outdoor irrigation.