Draft EIS/EIR for the San Luis Reservoir SRA Resource ...

5. Environmental Analysis
− Create or contribute runoff water that would exceed the capacity of
existing or planned stormwater drainage systems or provide substantial
additional sources of polluted runoff;
− Otherwise substantially degrade water quality;
− Place housing within a 100-year flood hazard area as mapped on a
federal Flood Hazard Boundary or Flood Insurance Rate Map or other
flood delineation map;
− Place within a 100-year flood hazard area structures that would impede
or redirect floodflows; or
- Expose people or structures to significant risk of loss, injury, or death
involving flooding, including that caused by dam or levee failures,
seiche, tsunami, or mudflow.
5.4.1.3 Environmental Evaluation
Facilities Maintenance and Construction Each of the alternatives include
maintenance or construction of sites and facilities including campgrounds, picnic
areas, boat ramps, boarding floats, shade ramadas, and buildings. Maintenance
and construction could expose loose soils, potentially increasing erosion and
siltation. Depending on the distance between the activity and the nearest Plan
Area waterbody, minor adverse impacts could occur to surface waters due to
erosion and a resulting temporary increase in turbidity or siltation in localized
areas. The addition of new paved surfaces could increase the amount of
impermeable surface within the Plan Area, potentially resulting in additional
runoff and pollutants in runoff. Moreover, the use of construction equipment and
related chemicals has a minor potential to result in the accidental release of
pollutants. Any release of pollutants could affect surface water, runoff, and
groundwater.
Maintenance and construction activities would have the potential to result in
minor, short-term adverse effects to water quality within the Plan Area. The
effects would vary by alternative as follows:
• Alternative 1, No Action/No Project, would not construct any additional
features or facilities in the Plan Area, but standard maintenance activities
would continue. These activities could have minor, short-term adverse
effects to water quality, but to a lesser degree than the action alternatives,
which all allow for additional construction.
• Alternative 2 proposes the fewest additional features and facilities of the
three action alternatives. The water quality effects described above could
result from expanding the group picnic facilities at San Luis Creek Use
Area and the campground at Los Banos Creek Use Area, as well as from
adding up to 30 tent sites at the northwest shoreline of San Luis Creek Use
Area. In addition, Alternative 2 would allow for reopening or relocating
the boat launch at Medeiros Use Area and removing sandbars in shallow
water areas. If these actions were pursued, potential impacts to water
quality from construction-related turbidity would range from minor to
major and would likely require second-tier environmental review. The
San Luis Reservoir SRA 5-11
Draft RMP/GP and Draft EIS/EIR