2000 Chevy Suburban Coolant leak on front side of motor

For the past few months, I have smelt a coolant leak on my suburban. No puddles anywhere though. The low coolant sensor seems to be quite sensitive, so when the overflow tank gets a bit low, the low coolant light comes on and I add a pint or so of collant. While completing an oil change yesterday (no water in the coolant..), I noticed a few orgae droplets on the underside and then pulled off the front plastic mud shield (6 bolts) that keeps rocks etc away for the belts. From there I would see dark streaks on the engine blcok coming down from teh water pump area.

I am wondering if I need a new water pump + gaskets...or maybe just new gaskets...