Title
Resolution Approving the Tidal Arch Public Art Sculpture with a Ten Percent Reduction in Overall Scale
Body
To: Honorable Chairperson Gillitt and Members of the Public Art Commission
EXECUTIVE SUMMARY
The Tidal Arch public art application, which presented a concept for a concrete and steel sculpture of approximately 80 feet in length and 17 feet in height, was approved by the Public Art Commission (PAC) in January of 2021. Due to engineering and logistical challenges identified by the project applicant, it has been determined that a ten percent reduction in the overall scale of the sculpture is necessary to ensure the artwork is structurally sound and can be moved from the fabrication site to the installation site.
The approximately ten percent overall reduction in the scope of the Tidal Arch is considered a substantial change from the proposal approved in January, 2021 and therefore requires additional consideration by and approval of the PAC. Staff believes that, although the size of the sculpture has been reduced, the design intent has been met, and recommends the approval of the ten percent reduction in scale of the Tidal Arch.
BACKGROUND
In January of 2021, the PAC approved the Tidal Arch public art application submitted by smErnst Development Partners at 1951 Harbor Bay. The artwork, designed by Adrien Segal, is proposed to be built using cast and formed concrete with structural steel and fasteners as needed. The sculpture takes inspiration from tidal ebbs and flows in San Francisco Bay and is designed to invite public interaction. The application approved by the PAC in January presented a sculpture of over 80 feet in length and approximately 17 feet in height at its highest point (see Exhibit A for the full proposal).
In October of 2021, the Building Permit for the Tidal Arch was sent to the Community Development Department for approval. The Building Permit included a rendering of the Tidal Arch, which shows a total length of 69’8”, or an approximate 10 percent reduction from the proposal application’s 80’3” (see Exhibit B for the rendering included with the Building Permit application).
Since the Tidal Arch application was approved, challenges related to on-site engineering as well as fabrication and logistics have arisen. The project’s structural engineer identified liquefaction concerns and proposed an in-ground engineering solution involving a foundation and Americans with Disabilities Act (ADA) slab endorsed by the project’s soils engineer. While neither the foundation nor ADA slab were included in the original cost estimate, these additional costs will be paid for by the project developer to ensure the concept intention is achieved as closely as possible.
The sculpture production process involves the digital fabrication of six unique elements and transportation by truck to the project site for installation. Following discussions between the artist and Concreteworks, the company selected to prepare the digitally fabricated concrete elements of the sculpture, it was determined that the proposed scale of the structure would be problematic from an engineering and logistical standpoint and that it would therefore be necessary to reduce the scale of the fabricated pieces because production at the scale shown in the original Tidal Arch concept would be prohibitively expensive.
Lastly, the project applicant and artist have notified the Community Development Department that Concreteworks is prepared to begin work on the structure as soon as all necessary permits are received. However, given the established production schedule and upcoming holidays, a significant delay in approvals may delay installation of the Tidal Arch, which is currently scheduled for Q1 2022.
DISCUSSION
According to conversations with the artists and project sponsor, the need to reduce the scale of the sculpture by approximately ten percent is necessary to make the sculpture, particularly the arch component, structurally sound. Furthermore, a reduction in scale is necessary for Concreteworks to digitally fabricate the molds, maneuver the parts safely once demolded, and deliver them to the project site without considerable increase in the cost of production. To understand the scale of the reduction, a graphic representation of the proposed Tidal Arch at 100%, 90%, and 80% of the concept design is shown in Exhibit C.
The approximately ten percent overall reduction in the scope of the Tidal Arch is considered a substantial change from the proposal approved in January, 2021 and therefore requires additional consideration and approval of the PAC.
While the project developer has agreed to cover the increased costs associated with the foundation and Americans with Disabilities Act (ADA) slab requirements not anticipated in the original $403,000 budget, the developer would be unable to cover the increased fabrication and logistics costs required to complete the Tidal Arch at the original concept scale.
Staff believes that, although the size of the sculpture has been reduced, the design intent has been met. Additionally, there is therefore a concern that if the PAC does not approve the ten percent reduction in scale, the project may no longer be feasibility. Accordingly, staff recommends approval of the ten percent reduction in scale of the Tidal Arch.
FINANCIAL IMPACT
The Tidal Arch is funded entirely by the project developer and there is therefore no direct financial impact to either City’s General Fund or Public Art Fund in approving the Tidal Arch at a reduced scale.
RECOMMENDATION
Approve the resolution of the Tidal Arch public art sculpture with a ten percent reduction in overall scale.
Respectfully submitted,
Lois Butler, Economic Development Manager
By,
Walker Toma, Development Manager
Exhibits:
1. 1951 Harbor Bay Parkway Application
2. Tidal Arch Building Permit Rendering (with reduced scale)
3. Tidal Arch 3 Scales