The diagrams below illustrate the basic lot grading requirements for all 5 different lot types of single-family and duplex.
Lot Type A
Rear to front surface drainage. (2-3% overall slope)
Lot Type A diagram
Grading Details
Lot Type B
Rear to front surface drainage. (3-6% overall slope)
Lot Type B diagram
Grading Details
Lot Type C
Rear to front surface drainage. (>6% overall slope)
Lot Type C diagram
Grading Details
Lot Type D
Standard split surface drainage. (1.5% overall slope)
Lot Type D diagram
Grading Details
Lot Type W
Split surface drainage for walkout basement.
Lot Type W diagram
Grading Details
Other Related Requirements
Critical Swale Standards for "Rear to Front" surface drainage (diagram)
Critical Swale Standards for "Split/Front to Back" surface drainage (diagram)
Infill Common Drainage Swale - (Detail B shows with retaining wall)
Splash Pad which carries roof leader and sump pump discharge away from foundation wall
Downspout which carries surface water from eavestroughs to drainage swales
Typical Side-Lot Landscaping shows landscaping requirements on finish grade level
Lake, Ravine, and Top of Bank Lots shows the cross-section of the requirements