Guerilla grow watering systems?

I have been planning a gorrilla grow in a couple different spots both have water fairly close but i cant leave a water pump sitin in the water source cause it would be to obvious. My question is what do all of you other guerilla growers do for water? i was thinking of collecting rain water but i heard some where that it would get stagnent and be bad for the crop so i was thinkin of putting a black cloth over a barrel to filter out bugs etc. and keep the light out plus keep anything bad from getting in there but would that even keep it from getting stagnent?. the only other thing i could think of is just takeing the pump out everytime i used it. any help,suggestions or infoetc is really appriciated because i am really confused about what to do thanks ahead of time.

Check out wick watering systems. Great idea if you don't intend on visiting your site that often. Plus you don't have to spend money on expensive pumps and timers and other equipment.

Dig a hole deep enough and route the water there. Better to save water than trying to find what to do with it IF any case water is not there anymore. What if the water doesn't run due to summer? Have to figure a way to get all that. Irrigation wise use PVC pipes. No need for timers. Use a manual valve. Works eat if used in sequence rather than at the same time. Works for me.

I use totes to collect rainwater, never had an issue even after the water has been sitting out for a month.