Drainage boundaries for selected subbasins in western Hampshire, western Hampden, and southeastern Berkshire Counties, Massachusetts, are delineated on 15 topographic quadrangle maps at a scale of 1:24,000. Drainage basins are shown for all U.S. Geological Survey data-collection sites and for mouths of major rivers. Drainage basins are shown for the outlets of lakes or ponds and for streams where the drainage area is greater than 3 square miles. Successive sites along watercourses are indicated where the intervening area is at least 6 square miles on tributary streams or 10 square miles along the Westfield or Farmington Rivers. (USGS)