Keep an eye on the leakage rate. It's kinda normal for 'a little' to leak, but make sure the leak isn't growing. And keep a close watch on your coolant level & engine temperature.

Water pumps usually don't quit pumping water when they fail. Either they start leaking or they start making noise. So if you hang on for a while make sure you pay attention to noise.

Don't wait too long, because the pump's driven by the timing belt. You really don't want the pump to make it throw the timing belt. When you eventually get it done, get a new timing belt at the same time. I'm betting it'll be much sooner than 90k for you...