It's false by adding access to waterways will have an greater impact on waterways.
Answer:
Explanation:
Lack of water, and food, being in the vast desert means hard food and little rain this leads to many organisms struggling to live, also being forced to drink dirtier water means you could catch a disease more easily
If your question is literally how long they could remain without water, the answer is 1-2 days with major side effects, and 3-4 with certain death.