A Facelift on Alcatraz Island

Words: Dan Kamys

Case Study: Rehabs and Restorations

QUIKRETE Cos. recently supplied shotcrete in 3,000-pound bulk bags for a restoration project on Alcatraz Island, also known as “The Rock.”

The QUIKRETE Cos. recently supplied shotcrete in 3,000-pound bulk bags for a restoration project on Alcatraz Island, also known as “The Rock.”

Boulderscape, a design architect specializing in shotcrete application, used QUIKRETE Shotcrete MS – Fiber Reinforced and QUIKRETE Shotcrete MS to successfully repair and stabilize a failing slope on the 22-acre island.

In addition to facing dangerous application conditions, a condensed six-week shotcrete schedule was required to avoid disruptions to regular tour operations, while considering the habitat and migration patterns of local sea birds. “Navigating a variety of unique factors made this a very fulfilling project for everyone,” says Steve Jimenez, senior VP commercial sales for Boulderscape. “We couldn’t start until the indigenous birds migrated from the island in November, and we had to complete our portion of the work before the birds returned in February. “This meant everything had to be expedited, starting with the delivery of material,” he continues. “Beyond the challenging schedule, the application process was full of danger. The nozzlemen had to be hoisted more than 60 feet in lifts to spray-apply the shotcrete before sculptors repelled down the cliff to shape the material. The end result was a structurally sound slope that matched the surrounding environment.” In one weekend, 131 bulk bags of Shotcrete MS – Fiber Reinforced and 126 bulk bags of Shotcrete MS were delivered to Alcatraz Island for the project. QUIKRETE delivered16 truckloads of material to Pier 50 in San Francisco that were later shipped on two barges to Pier 33 on Alcatraz Island. It was offloaded at night by crane, one-by-one, before finally being transported to the jobsite on trailers pulled by four-wheel, all-terrain vehicles. Shotcrete MS – Fiber Reinforced is a single-component Micro Silica enhanced repair and restoration material that achieves more than 9,000 PSI at 28 days, and features very low rebound and permeability characteristics.
For more information on QUIKRETE and its products, visit www.quikrete.com, like it on Facebook and follow it on Twitter @QUIKRETE.
About: Case Study
Beyond the Block: Aesthetic Innovations in CMU Construction
August 2026

Concrete masonry units (CMUs) have long been a mainstay of construction. They are well known as a “tried and true” material with a long history of high-strength structural performance, affordability, ease of assembly, and a long lifecycle. CMU constructio

The Most Overlooked Profit Center on Your Job Site
August 2026

The real cost of equipment ownership isn't what you pay on day one. It's what happens over the years that follow. The purchase price of a new mortar mixer, grout pump, material handling system, or masonry saw is only part of the investment. What happens

Installation Starts Before the First Course
August 2026

Some of the most expensive masonry installation problems begin long before crews arrive onsite. By the time a project reaches the field, many coordination decisions have already been made. Dimensional conflicts, congested reinforcement, specialty materia

Designing for Performance: Key Considerations for Efficient, Durable Masonry Projects
August 2026

A successful masonry project starts well before the first stone is set. The craftsmanship on site matters, of course, but many of the decisions that shape the final result are made much earlier—during design, detailing, and material selection. Those choic