Repairs were done over the winter when lilies are dormant.
Participants in the water fight, which was advertised on social media, trampled landscaping, damaged planters and busted a pipe that nearly drained the pond.
Donations raised by Friends of Balboa Park paid for the repairs. While they were at it, workers rebuilt 27 boxes that house lily pads, installed new pipe and relined the rim with new plaster.
A celebration is scheduled at 9:30 a.m. Monday to celebrate completion of the work.