3.2 Water Quantity
- Drainage is conveyed through the
subwatershed through culverts and small channels to wetlands, most of
which are ditched or drain to Painter Creek. The Upper
Watershed Stream Assessment identified 11 locations on the Creek with
erosion or bank failure, most of them concentrated in about 1400 linear
feet of that study’s Reach 1. The
HHPLS included a study of scour potential in the creek, and concluded that
some reaches were at moderate to high risk for erosion.
- The HHPLS identified three locations that
are predicted to overtop during the 100 year event: two driveways and a
location on Ingerson Road.
More detail is available in the
HHPLS. Local plans should identify
these observed or potential locations and assess whether the risk of
occasional flooding is acceptable or should be addressed.
- The HHPLS identified two locations
requiring special attention: the outlet of Katrina Lake
and the outlet of the Highway 26 marsh.
Excessive cattail growth can limit the operation of the lake outlet. At the outlet of the Highway 26 marsh, a
channel has formed around the outlet bypassing the control structure.
- Development, redevelopment, and
reconstruction in the subwatershed may increase the volume of stormwater
runoff, increasing nutrient and TSS loads conveyed downstream.
- The HHPLS identified several locations
where for both existing and future conditions higher velocities than
desired may result in erosion at outlets or culverts. These
include three crossings of CR 6, and a crossing of Ingerson Road west of Painter Marsh.
Erosion control or energy
dissipation measures may be required in those locations.