Main . Letter From The Superintendent . Table of Contents . Finding of No Significant Impact . Errata Sheets: Part 1, Errors & Clarifications . Errata Sheets: Part 2, Summary of Substantive Public Comments & Responses . Merced Wild and Scenic River Section 7 Determination . Wetland Statement of Findings . Floodplain Statement of Findings
Yosemite Home . Yosemite Planning PageWetland Statement of Findings
Purpose of this Statement of Findings
The purpose of this Wetland Statement of Findings is to review the East Yosemite Valley Utilities Improvement Plan in sufficient detail to:
♣ Avoid, to the extent possible, the short-and long-term adverse impacts associated with the destruction or modification of wetlands and to avoid direct or indirect support ofnew construction in wetlands wherever there is a practicable alternative
♣ Describe the effects on wetland values associated with the Selected Alternative
♣ Provide a thorough description and evaluation of mitigation measures developed to achieve compliance with Executive Order 11990 (Protection of Wetlands) and National Park Service Director’s Order 77-1 and Procedural Manual77-1: Wetland Protection
♣ Ensure “no net loss” of wetland functions or values
Wetlands and deepwater habitats within the project area include the riverine habitat of the Merced River and numerous areas of palustrine forest, palustrine scrub shrub, and palustrine emergent within the Merced River corridor. A total of approximately twenty-sixacres of riverine and palustrine wetland habitat occur within the project area. Wetland and aquatic habitats that may be affected are predominately associated with the Merced River corridor and several creeks that cross through the area.
Specific wetland classes identified within the project area are limited to riverine (rivers, creeks, and streams) and palustrine(shallow ponds, marshes, swamps, and sloughs). Using the Cowardin classification, specific wetland and deepwater classes within the project area include:
♣ Palustrine emergent – 18.86 acres of herbaceous (e.g., sedge, rush, grass, etc.) habitat within the Merced River corridor subject to various runoff and flooding regimes
♣ Palustrine forest – 1.84 acres of riparian foresthabitat within the Merced River corridor subject to various runoff and flooding regimes
♣ Palustrine scrub shrub – 0.40 acres of riparian scrub (e.g., willow) habitat within the Merced River corridor subject to various runoff and flooding regimes
♣ Riverine habitats – 4.90 acres of active channels of the Merced River, its tributaries, and other intermittent streams in the projectarea
The size, connectivity, and integrity of wetlands in the project area, particularly palustrine forest, palustrine scrub shrub, and riverine habitat, have been directly compromised by development and visitor activities. A description of the specific wetland and deepwater classes within the project area follows.
Emergent wetlands are the most extensive Cowardin class in the projectvicinity. They occupy large expanses of land comprising four different meadow communities: Carex senta wet meadow, grass/sedge meadow, mixed meadow, and Indian hemp meadow. These wetlands are characterized by a relatively dense layer of herbaceous vegetation that tends to be dominated either by obligate sedges or by a mixture of hydrophytic grasses, sedges, and forbs. The Carex senta wet meadow andgrass/sedge meadow communities are the most common, occupying extensive areas on low, intermediate, and high stream terraces throughout the project vicinity. Carex senta wet meadow contains mostly pure stands of rough sedge and creeping wild-rye with woolly sedge and cow parsnip as associates. Grass/sedge meadow emergent wetlands typically have a continuous coverage of slender-beak sedge and...