Chapters 1 - U.S. Fish and Wildlife Service

Chapter 5
would ensure that no significant adverse impacts related to hydrology and flooding would result
from the implementation of Alternative B.
Public Use
The continuation of the limited public use program proposed under Alternative B would not result
in any significant adverse effects to local hydrology on the Refuge or beyond the Refuge boundary
in Anaheim Bay.
5.2.2.6 Effects to Water Quality
Wildlife and Habitat Management
Habitat restoration and enhancement proposals included under Alternative B that could have an
effect on water quality include the grading activity associated with the restoration of tidal influence
to approximately 36 acres within the Refuge, as well as activities associated with replacing existing
culverts, including the culverts in the Bolsa Levee. These actions have the potential to increase
erosion and sedimentation into adjacent wetland areas, particularly during storm events. Excess
sediment in runoff from a construction site both during and after construction can cause increased
turbidity in natural water systems, reducing the amount of sunlight reaching aquatic plants, such
as eelgrass, clogging fish gills, and blanketing aquatic habitat and potential spawning areas with
silt. Sediment introduced into adjacent waterway can also transport other pollutants such as
nutrients, metals, and oils and greases into adjacent wetlands. These effects can be avoided
through appropriate construction design and construction activity.
To avoid such water quality impacts, the construction specifications for each individual restoration
project would include the requirement to implement appropriate BMPs. These BMPs could
include the use of silt fencing, straw wattles, and filter fabric to prevent the introduction of exposed
soils into adjacent wetland areas, the installation of cofferdams during construction, proper
maintenance and fueling of construction vehicles to avoid spills and tracking of dirt onto public
roadways, and appropriate erosion control techniques following construction to minimize the
potential for erosion while the desired vegetation becomes established. With the implementation
of appropriate BMPs, no adverse effects to water quality within the Refuge or Anaheim Bay would
occur as a result of any ground disturbing activities proposed under Alternative B.
The potential for impacts to water quality would be further reduced by the implementation of a
Storm Water Pollution Prevention Plan (SWPPP) during construction, as required by the State of
California as part of the California NPDES General Permit for Storm Water Discharges
Associated with Construction and Land Disturbance Activities. Coverage under this General
Permit, which involves electronically filing the Permit Registration Documents (i.e., Notice of
Intent, SWPPP, and other compliance related documents required by this General Permit) with
the State, would be obtained for all construction projects on the Refuge, including restoration
projects, which disturb one or more acres of land surface.
Alternative B also proposes the implementation of a water quality monitoring program to regularly
collect data on the basic physical parameters of the waters within the Refuge. Additionally, Refuge
staff would participate in other federal, state, and local agency activities related to the
improvement of quality of water throughout the watersheds that ultimately empty into Anaheim
Bay. Through such a multi-agency partnership, the Refuge would seek to implement measures
that would reduce the level of pollutants in the Bolsa Chica and East Garden Grove-Wintersburg
channels that could adversely affect habitat quality and trust resources on the Refuge. To the
extent that its aims could be achieved, this proposal’s effects on water quality would be beneficial.
5-16 Seal Beach National Wildlife Refuge