96 Chev PU Leaking water from intake manifold??

4.2 V6 - 160,000 miles. It has been losing water for a while and I
finally found what I think it is - it appears that water is leaking
from between intake manifold and block at left front of engine (behind
alternator, of course). There is no water in oil. Is it safe to keep
driving it or can the water get into the motor? Is this a normal thing
that goes wrong - what causes it and how do I fix it? I guess the
manifold gasket has gone bad which means I have to remove the intake
and replace the gasket?

Thanks,
Libby