Chapter 4 Cumulative Effects

Transcription

1 Chapter 4 This chapter reevaluates the likely level of cumulative effects to which the Elliott Bay Seawall Project could contribute, given the proposed changes to the project, and determines whether these changes have the potential to affect long term trends in the project area. In contrast to the potential direct and indirect effects discussed in Chapter 3, cumulative effects are those that could result from the combined incremental impacts of multiple actions over time. The purpose of a cumulative effects analysis is to identify the potential for the project to contribute to these incremental impacts to a degree that, if left unmitigated, could cause them to reach significant proportions. It is also helpful for decisionmakers in evaluating how sustainable a proposed project is likely to be and how it might interact with other projects that are reasonably foreseeable but have not yet been built. In the Central Seawall area, these other reasonably foreseeable future actions (RFFAs) include the Alaskan Way Viaduct Replacement Project, Waterfront Seattle projects, and the Seattle Multimodal Terminal at Colman Dock Project. 4.1 How were Evaluated for the Elliott Bay Seawall Project As described in Chapter 6 of the EIS, the cumulative effects analysis considered the relationships between the direct and indirect effects of the project, past and present actions, and other RFFAs on the resources of concern. The temporal boundaries of the analysis, the list of RFFAs, and the description of project area history have not changed since the EIS. Figure 4 1 shows the RFFAs; please refer to Chapter 6 of the EIS for more detailed information. The areas of analysis for cumulative effects in this SEIS include transportation; economics; noise and vibration; land use; social resources and environmental justice; water resources; and fish, wildlife, and vegetation. For other disciplines evaluated in the EIS, the proposed updates to the Preferred Alternative would not result in any impacts that could add to the incremental impacts of other past, present, and reasonably foreseeable future projects. The design and construction changes that were evaluated for potential contributions to cumulative effects include: Elimination of the summer construction shutdowns Closure of most businesses on Piers 54 through 57 to facilitate construction in Zone 3 Changes to transportation, including relocation of the ferry queue to the south of Colman Dock beginning as soon as summer 2014 Changes to aspects of in water construction, primarily related to the temporary containment wall Changes to aquatic habitat enhancements Defining Cumulative Effects SEPA requires that cumulative effects be considered in an EIS (WAC ). Although SEPA does not specifically define cumulative effects, the term is defined under the National Environmental Policy Act (NEPA) as the impact on the environment which results from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions regardless of what agency (Federal or non Federal) or person undertakes such other actions. Cumulative effects can result from individually minor but collectively significant actions taking place over a period of time. (40 CFR ) Draft Supplemental Environmental Impact Statement December 2013 Page 4 1

2 CUMULATIVE EFFECTS Figure 4-1. Reasonably foreseeable future actions in the Elliott Bay Seawall Project vicinity December 2013 Page 4 2 Draft Supplemental Environmental Impact Statement

3 4.2 Transportation The temporal boundaries, past and present actions, and RFFAs for transportation have not changed from the Final EIS analysis; see Section 6.3 of the Final EIS for more information. Cumulative effects of the No Action Alternative are also the same as in the Final EIS. The primary transportation related changes in the Updated Preferred Alternative are the continuation of construction during the summer seasons and the relocation of ferry queuing to the south of Colman Dock, beginning as soon as summer As described in Section 3.1 of this Draft SEIS, construction during the summer months is not expected to result in any additional impacts compared to those described in the Final EIS, because summer traffic volumes were used in the original analysis. The City developed the concept of relocating the ferry queue jointly with Washington State Ferries, in part as a way to alleviate congestion caused by multiple overlapping projects along the waterfront. The change in ferry access would not have significant effects on traffic operation in the project area compared to the baseline; therefore, the Updated Preferred Alternative would not result in any incremental adverse cumulative effects to transportation beyond those described in the Final EIS. Mitigation for As described in the Final EIS, the City will focus mitigation measures on minimizing construction related impacts. The City will continue to coordinate with King County Metro, WSDOT, the Port of Seattle, Sound Transit, local businesses, and neighborhoods to coordinate construction sequencing between projects. 4.3 Economics The temporal boundaries, past and present actions, and RFFAs for economics have not changed from the Final EIS analysis; see Section 6.4 of the Final EIS for more information. Cumulative effects of the No Action Alternative are also the same as in the Final EIS. The primary changes to economic impacts from the Updated Preferred Alternative are the closure of businesses on Piers 54 through 57 and the continuation of construction through the summer months. As described in Section 3.2 of this Draft SEIS, the temporary business closures are expected to result in revenue losses of between $11.1 and $18.6 million, the temporary layoff of as many as 245 employees, and a reduction in sales tax of up to $2.3 million. In addition, extending Draft Supplemental Environmental Impact Statement December 2013 Page 4 3

4 construction through the summer has the potential to reduce overall business revenues in the area beyond the levels identified in the EIS as a result of reduced access and disruption. These effects would add to the business disruptions caused by other active projects occurring concurrently in the central waterfront area. Although they are cumulatively substantial, all of the effects are temporary, and once mitigated are not likely to result in long term adverse impacts to the economic viability of the waterfront businesses or the larger regional economy. The long term cumulative economic effect of the Elliott Bay Seawall Project and the RFFAs continues, as described in the Final EIS, to be positive. Mitigation for As described in the Final EIS, SDOT will coordinate with other City departments, WSDOT, and others to minimize the combined construction related effects of concurrent projects in the vicinity of the seawall. In addition, the City will compensate business owners for the loss of access to their businesses during the closure period. 4.4 Noise and Vibration The temporal boundaries, past and present actions, and RFFAs for noise and vibration have not changed from the Final EIS analysis; see Section 6.5 of the Final EIS for more information. Cumulative effects of the No Action Alternative are also the same as in the Final EIS. Given the existing high levels of noise in the project area, ongoing construction of the Alaskan Way Viaduct Replacement Project, and the wide range of noise generating construction activities evaluated in the EIS, the Updated Preferred Alternative is unlikely to further increase cumulative noise levels. The potential exception is the use of pumps associated with the proposed water treatment system. If not attenuated, noise from these pumps, in combination with construction activities from the RFFAs, could increase ambient noise levels on a continuous basis for 2 to 3 years in the surrounding area. Cumulative levels of vibration are not expected to increase compared to the Final EIS as a result of the proposed updates to the Preferred Alternative. Mitigation for If used, attenuation measures would reduce pumping noise to levels consistent with the project noise variance, eliminating the potential incremental addition to cumulative effects. Otherwise, mitigation for cumulative noise and vibration effects would remain as proposed in the Final EIS. Construction activities would comply with all applicable noise regulations. December 2013 Page 4 4 Draft Supplemental Environmental Impact Statement

5 4.5 Cultural, Historic, and Archaeological Resources The temporal boundaries, past and present actions, and RFFAs for cultural, historic, and archaeological resources have not changed from the Final EIS analysis; see Section 6.6 of the Final EIS for more information. Cumulative effects of the No Action Alternative are also the same as in the Final EIS. The analysis of cultural, historic, and archaeological resources did not identify any additional adverse effects for the Updated Preferred Alternative, and two previously identified potential adverse effects were eliminated because the resources were deemed not eligible for NRHP listing. Therefore, the Updated Preferred Alternative would have no additional incremental effects on cultural, historic, and archaeological resources. Mitigation for The construction related mitigation measures described in Section 4.4 of the Final EIS will avoid or minimize the cumulative effects of the proposed alternatives that will occur during construction. SDOT will coordinate the construction of the proposed projects with all other applicable agencies to minimize the effects on historic and archaeological resources. 4.6 Land Use, Shorelines, and Parks and Recreation The temporal boundaries, past and present actions, and RFFAs for land use, shorelines, and parks and recreation have not changed from the Final EIS analysis; see Section 6.8 of the Final EIS for more information. Cumulative effects of the No Action Alternative are also the same as in the Final EIS. The proposed changes to the Preferred Alternative would shift the timing of construction related effects on land use and shorelines and on parks and recreation, but they would not change their intensity during the additional months of summer construction. Therefore, there would be no change to the cumulative effects described in the Final EIS. Mitigation for The City will coordinate active public information efforts for construction of the Elliott Bay Seawall Project with other projects in the vicinity to provide a consistent and comprehensive approach to Draft Supplemental Environmental Impact Statement December 2013 Page 4 5

6 informing the public of accessibility to the waterfront, available parking, and transit options. Project staff will work closely with Seattle Parks and Recreation and the Seattle Aquarium to make sure that the project provides flexibility for future redevelopment or expansion of Waterfront Park, Pier 62/63, and the Seattle Aquarium. 4.7 Social Resources and Environmental Justice The temporal boundaries, past and present actions, and RFFAs for social resources and environmental justice have not changed from the Final EIS analysis; see Section 6.10 of the Final EIS for more information. Cumulative effects of the No Action Alternative are also the same as in the Final EIS. In general, the effects would be very similar to those described in the Final EIS. The main difference would be the loss of as many as 245 jobs for the anticipated 9 month business closure on Piers 54 through 57. Although the loss of these jobs could create economic hardship for some individuals, it is unlikely even in combination with adverse construction effects of the RFFAs to contribute to overall levels of poverty in Seattle or the region. Over the long term, the Elliott Bay Seawall Project, in combination with other projects in the area, is likely to contribute to beneficial effects on social resources and environmental justice populations, including improved mobility and safety along the downtown Seattle waterfront. Mitigation for Beyond the mitigation proposed in the Final EIS for construction effects on social resources and environmental justice populations, no further mitigation for cumulative effects is needed. 4.8 Visual Resources The temporal boundaries, past and present actions, and RFFAs for visual resources have not changed from the Final EIS analysis; see Section 6.11 of the Final EIS for more information. Cumulative effects of the No Action Alternative are also the same as in the Final EIS. The cumulative effects, in combination with concurrent construction activities of RFFAs, are likely to be very similar to those described in the Final EIS. While construction during summer months may expose a larger population of viewers to December 2013 Page 4 6 Draft Supplemental Environmental Impact Statement

7 the visual clutter of construction activities, the activities themselves would not change. All effects would be temporary and would cease at the end of construction. Over the long term, the Elliott Bay Seawall Project, in combination with the other RFFAs, likely would contribute to improved visual character and visual quality in the project area. Mitigation for The project would result in only minor temporary cumulative effects on visual quality, and most of the effects would be beneficial. Therefore, no mitigation for cumulative effects on visual resources is proposed. 4.9 Fish, Wildlife, and Vegetation The temporal boundaries, past and present actions, and RFFAs for fish, wildlife, and vegetation have not changed from the Final EIS analysis; see Section 6.12 of the Final EIS for more information. Cumulative effects of the No Action Alternative are also the same as in the Final EIS. Construction, in combination with concurrent construction activities of RFFAs, would result in cumulative effects only slightly different than those described in the Final EIS. The reduced size of several aquatic habitat features would minimize the cumulative disruption to aquatic habitat during construction. Cutting off the temporary sheet pile containment wall at the end of construction, rather than vibrating it out, would also reduce overall habitat disruption. Conversely, the cumulative benefit of habitat enhancements in Elliott Bay would also be slightly reduced by the reduction or elimination of previously proposed habitat area. Nevertheless, the project would continue to contribute to a cumulative beneficial effect on the Elliott Bay nearshore ecosystem. Mitigation for The Elliott Bay Seawall Project and all other construction projects in the area will need to adhere to permit conditions and regulations that protect fish, wildlife, and vegetation Water Resources The temporal boundaries, past and present actions, and RFFAs for water resources have not changed from the Final EIS analysis; see Section 6.13 of the Final EIS for more information. Cumulative effects of the No Action Alternative are also the same as in the Final EIS. Draft Supplemental Environmental Impact Statement December 2013 Page 4 7

8 As discussed in Section 3.10 of this Draft SEIS, the proposed changes to upland and in water work could result in slight localized increases in turbidity in Elliott Bay near the seawall. The City will implement BMPs and appropriate plans during construction to avoid, minimize, and mitigate potential effects to water quality during construction. In combination with concurrent construction activities of the RFFAs and the other project effects evaluated in the Final EIS, the project is not expected to contribute substantially to cumulative effects on water quality. Long term stormwater treatment measures included in the Elliott Bay Seawall Project and the RFFAs would still provide a cumulative benefit to water quality in Elliott Bay. Mitigation for No long term adverse cumulative effects to water quality are anticipated that will require additional mitigation. December 2013 Page 4 8 Draft Supplemental Environmental Impact Statement