About the Tower

Sutro Tower™ stands 977 feet high on San Francisco’s Mount Sutro, with its base at an elevation of 834 feet. Its highest antennas are 1811 feet above sea level, so clear signals can be transmitted throughout the Bay Area. Its three legs are embedded in 15 million pounds of cement, and its towers are made of 3.5 million pounds of steel.

Sutro Tower Dangling

Slideshow of workers on Sutro Tower

Sutro Tower, Inc. has submitted final permit applications to the San Francisco Planning Department to install new antennas mandated by the Federal Communications Commission, and to reduce the wind load and weight of the tower for safety. Antenna reconfiguration requires structural enhancement subject to newer building codes, which include managing the forces of winds of more than 100 mph. The safest way to strengthen the tower is to reduce its weight and lessen the wind forces. Therefore, 1,500 siding panels will be removed from the structure’s legs – creating “open truss legs” similar to the Eiffel Tower and most bridges.

New Siding Project (pdf)

New Antennas Project (pdf)

Sutro Tower received approval from the San Francisco Planning Commission in March 2015 to install additional antennas and for site improvements. Here are the permit applications that were approved:

Building permit for tower modifications (pdf)

Simulated photo of new antennas

Site work permit:
Section 1 (pdf) –Section 2 (pdf)

Sutro Tower Configuration

Sutro Tower diagramclick to enlarge

In 2016 Sutro Tower received permits to install a low-power FM antenna, to replace three microwave antennas, and to add plants and screens for aesthetic purposes. Here are the proposals:
Sprint-Clearwire Antenna
Building Permit #:  2015-12-08-4464
The client replaced three old microwave antennas with three new microwave antennas.
Antenna Screening Project
Building Permit Number:   2016-0216-9652
This project proposes to move dish antennas back from the edge of the building and install a translucent screen on the eastern side of the building facing the reservoir.
Antenna Screening Elevation
KQEA Low Power FM Antenna
Permit Number: 2015-07-21-2069
This client installed one 68-pound antenna on the North leg of the tower at 230 feet above ground.

This project replaced the trees and shrubs removed in previous years from SFPUC property, restored some plants removed by previously approved projects, and changed some elements of the building to make it more appealing to hikers at Summit Reservoir. Permit Numbers: 2016.02.16.9635, 2016.02.16.9652