GRANT ROAD DRAINAGE DESIGN – SEGMENT 4

Gradient Group, LLC was selected by Harris County Pct. 4 Commissioner Jack Cagle to conduct the drainage design associated with the widening of Grant Road for 2.4 miles from a 2-lane open ditch roadway to a 4-lane boulevard section between Telge Road and Cypress Rosehill in northwest Harris County. Gradient was also responsible for preliminary drainage engineering & detention study and final drainage (storm-sewer) design. Gradient perform an analysis to define existing drainage areas and drainage patterns along the roadway and evaluate changes to the existing conditions as a result of the proposed roadway alignments.  We evaluate sheet flow drainage patterns along the roadway corridor to define runoff flows from within 150 feet of the ROW versus runoff defined by the existing drainage areas based on LiDAR topography and HC drainage criteria. Coordinated with HCFCD concerning participation in the Little Cypress Creek Frontier Program and identify opportunities for regional detention applications.  We identify possible outfall locations and detention sites necessary to accommodate runoff from the proposed roadway improvements.  Finally prepared a Storm Water Pollution Prevention Plan (SWPPP) including drawings based on HC criteria.