i would use rocks to stop up your creek.in my overflow pipe discharge ditch i use rocks that are from softball size to half the size of a basketball to raise the water in my lake.in my case i've probably raised the water level about 3-4 inches in a 5 1/2 acre lake.this seems to work pretty good for me and it does not cost any money.i would think you could easily hold back as much water as you would need.