Heavy rain that occurs on the State University of Malang campus often results in puddles. With the large water catchment area in the campus area and the many locations where rainwater pools, it is necessary to research how much rainwater can be collected. The methodology used includes collecting rain data, observing inundation locations, calculating rain using the ranking method, rational method debit calculations, water balance calculations, and storage size calculations. From the survey results, the locations that can be used as reservoirs consist of 14 locations. The area of the catchment area that has the potential to drain water into the reservoir is 69,845.10 m2. The storage capacity calculation results obtained: G1 = 178.50 m3, G1 = 80 m3, G3 = 75 m3, G4 = 108 m3, G5 = 97.5 m3, G6 = 93.6 m3, G7 = 84 m3, G8 = 22.5 m3, G9 = 67.2 m3, G10 = 83.2 m3, G11 = 41.6 m3, G12 = 36.4 m3, G13 = 65 m3, G14 = 65 m3. The amount of standing water that can be accommodated in the storage pond is 852.72 m3. The amount of standing water that can potentially be stored for 1 year is 19,553.98 m3.