I read being dehydrated can be a cause of heart palpitations. so then how many ounces of water a day for adult female, lightly active, 130lb?

Marketing, Marketing: While dehydration may ↑ heart rate & palpitations, especially for those already demonstrating these behaviors, it is not a primary cause, only another variable. In comfortable environment, young people in good health can get by, indefinitely, on as little as 0.5 Liter/day up to as much as 25 Liters/day (a 50-fold range) of liquid intake (all liquids, most of which=water); thus no reliable amount.