  Observations of the 1(10)-1(01) 556.936 GHz transition of ortho-water with
the Submillimeter Wave Astronomy Satellite (SWAS) have revealed the presence of
widespread emission and absorption by water vapor around the strong
submillimeter continuum source Sagittarius B2. An incompletely-sampled spectral
line map of a region of size 26 x 19 arcmin around Sgr B2 reveals three
noteworthy features. First, absorption by foreground water vapor is detectable
at local standard-of-rest (LSR) velocities in the range -100 to 0 km/s at
almost every observed position. Second, spatially-extended emission by water is
detectable at LSR velocities in the range 80 to 120 km/s at almost every
observed position. This emission is attributable to the 180-pc molecular ring
identified from previous observations of CO. The typical peak antenna
temperature of 0.075 K for this component implies a typical water abundance of
1.2E-6 to 8E-6 relative to H2. Third, strong absorption by water is observed
within 5 arcmin of Sgr B2 at LSR velocities in the range 60 to 82 km/s. An
analysis of this absorption yields a H2O abundance ~ 2E-7 to 4E-7 relative to
H2 if the absorbing water vapor is located within the core of Sgr B2 itself;
or, alternatively, a water column density ~ 2.5E+16 to 4E+16 per cm2 if the
water absorption originates in the warm, foreground layer of gas proposed
previously as the origin of ammonia absorption observed toward Sgr B2.
