The Jackson Bayou watershed is located in east Harris County, just east of Lake Houston, and serves the Crosby and Newport areas. The watershed covers about 25 square miles and flows into the San Jacinto River below Lake Houston via Jackson Bayou. There are about 36 miles of open streams within the watershed, including the primary stream and tributary channels. Gum Gully is the largest tributary in the watershed and drains about 17 square miles, which is close to 70% of the watershed. Based on the 2010 U.S. Census, the estimated population of the Jackson Bayou watershed is 14,014.
Although erosion problems exist along most of the length of the Jackson Bayou and its tributaries, little or no regional planning has been done for Jackson Bayou due to the low incidence of structural flooding. Jackson Bayou is relatively deep with steep side slopes and the channel slope is relatively steep (for Harris County) which promotes rapid drainage of the watershed. Some flooding of a few structures has occurred in the last twenty years, although the mapped floodplain typically covers farmland and areas with scattered development. The floodplain in the lower portion of the watershed results from the San Jacinto River.