Environmental Impacts
Extensive studies have been performed as part of the preparation of the Draft Environmental Document. The following is a summary of key points.
Hydrology and Floodplain
- Project will add no more than 1.0 acre of additional impervious surface area
- No significant encroachment into a 100-year floodplain
Water Quality
- No increase in pollutants during operation of the project
- Temporary best management practices will be employed to limit impacts during construction
Hazardous Waste/Materials
- Five sites with potential hazardous waste or material concerns were identified within (or near) the project footprint
- Contamination may be present in soil and groundwater and will be properly transported and disposed of, if encountered
Community Character/Cohesion
- No displaced residences, businesses, or community facilities
- Increased connectivity between neighborhoods and to Chinese Garden Park and Neptune Park
- Parking loss in downtown Oakland to accommodate safety, connectivity and accessibility for pedestrians and active transportation improvements
Noise/Vibration
- Noise levels in the design year will remain at existing levels
- Noise abatement measures were evaluated because existing conditions in the project footprint are at (or near) the Noise Abatement Criteria
- Vibration measures will be employed during construction to avoid damage to nearby structures, including historic buildings
Biological Resources
- No impacts to federally listed threatened or endangered species
- No impacts to sensitive habitats, such as streams and wetlands
- Tree removal (approximately 35 trees) will occur and replacement will occur where feasible
- Preconstruction bird/bat surveys will be conducted to avoid impacts
Air Quality
- Not a Project of Air Quality Concern (POAQC)
Right-of-way
- No displaced residences and businesses and no full property acquisitions anticipated
Visual/Aesthetics
- Overall, the project will enhance the visual environment due to expanded views of the horizon, landscaping, and reduction of light shadowing with removal of the Broadway off-ramp
- Mitigation is proposed for visual impacts to the Posey Tube
- Tree clearing will be offset by proposed landscaping
- Retaining walls will be treated with color, texture and/or patterning to enhance aesthetics and reduce the likelihood of glare and/or graffiti.
Parks and Recreational Facilities
- Approximately 1.52 miles of additional bike infrastructure will be built, improving connectivity within the project area
- A sidewalk will be widened within Neptune Park in Alameda and a standard Class I bike facility will be provided
- Continuous sidewalks will be constructed around Chinese Garden Park in Oakland
- Access to parks will be maintained at all times during construction
Climate Change
- No additional greenhouse gas emissions during project operation
Traffic/Transportation
- Existing parking will be reduced in Oakland to accommodate project improvements
Cultural Resources/Section 4(f)
- Adverse Effect on the Posey Tube (eligible for listing on National Register of Historic Places [NRHP]) and the Oakland Waterfront Warehouse District (NRHP-listed)
- Memorandum of Agreement being prepared with the State Historic Preservation Officer (SHPO) and other consulting parties
- Individual Section 4(f) Evaluation prepared for impacts to the Posey Tube and the Oakland Waterfront Warehouse District
- New right-turn lane from the Posey Tube to 5th Street would cause demolition of approximately 175 feet of the eastern wall
- New left-turn lane from Posey Tube to 6th Street would cause demolition of approximately 100 feet of the western wall
- Staircase removal on eastern wall of Posey Tube for installation of ADA-compliant ramp
- Final design for new wall will be completed in consultation with SHPO and other consulting parties

Existing (L) and proposed (R) Harrison Street Looking East toward I-880

Existing (L) and proposed (R) Harrison Street Looking South at the Posey Tube
Paleontology
- Geology in the Oakland portion of the project footprint has a high potential to contain scientifically important paleontological resources
- Project may encounter fossils
- Construction crews will receive environmental awareness training
- A paleontological monitor will be on-call during construction
- Any observed fossils will be evaluated, and if significant, will be recovered and donated to a recognized institution