My clay soil is cracking with some deep chasms forming in open areas, which just goes to show that open areas are bad news. Exposed clay soil can open up roots to dry air and sunlight. So we need to think about layering and planting densely where we can to shade soil, increase water penetration, enrich soil, compete against weeds and make for a better looking space overall.
All this being said, of my 5,000' only a few news plants get a drink in these hot days. Besides, out front, both of my neighbor's sprinkler systems shoot way over into my drought-tolerant prairie beds, and the one waters twice a day in high wind about late afternoon. I tell you what. You shouldn't have to plan a garden taking into account neighborhood over watering.