It will probably depend on what kind of soil you have (sandy, clay, high or low amount of organic matter, etc) and your local climate, but there is a chart from Texas A&M that shows the general number of inches of water that various veggies require in that climate (below), but generally how they're broken down is:

High water needs:
Onion, pepper, pumpkin (highest)
Then broccoli, cabbage, cauliflower, slicing cucumber, eggplant, potato, sweet corn, tomato.

Moderate water needs:
Beans, cantaloupe, pickling cucumbers (higher)
Asparagus, cowpea.

Lower water needs:
Mustard greens, spinach, turnip, watermelon (more)
Lettuce
Radish (least)

Sue

Here is a link that might be useful: Relative vegetable water needs chart

Thank you Sue. I checked out the link and that is precisely the type of data I was looking for. I know that variables will effect things but the concept of the ratio should still hold mostly true. Essentially the ratio of water is set by the size of the holes (mostly uniform) or rating of emitters used and the pressure of the system. The overall amount of water given though is independent and set by the time and frequency of watering. Thus you set the ratio and overall amount separately. If the ratio is right then when you turn on the system long enough to water the tomatoes then you also properly water the spinach because it was getting water at a lower rate.

Now if I the list could be fleshed out a bit that would be even better. What about winter squash for example? Also do both hot peppers and bell peppers fit the same water needs where the list has just peppers? Do pole beans, bush garden beans and snow peas all have similar needs and is that approximately the same as the pinto beans in the list?

So If I was to put the plants that like more water on the west and the plants that like less on the east it would be in this order? West end first, Onion, hot and sweet Pepper, potato, broc, cabbage, cucumber, tomaoto, beans and canteloupe. I always thought canteloupe liked more water than peppers.