San Francisco PUC Built State-of-the-Art Sustainable Headquarters

You are the general manager of the San Francisco Public Utilities Commission. Your new headquarters, which opened in June of 2012, set a new standard for high-performance structures. Describe the building and how it came to be.

Harlan Kelly: We are proud to be the owner of one of the greenest buildings in the nation. It is a LEED Platinum headquarters and embodies our core agency mission and values. It’s a model for cost-saving sustainability for customers and utilities. 

We moved out of a place that we were leasing. The rates were increasing and so we considered whether we should continue to rent or build a new headquarters. We decided that the wiser long-term investment was to invest in this amazing building.

Fortunately, we built it at a time when the construction cost was low. We’re actually saving our ratepayers $3.7 billion over the lifespan of the building, as compared to continuing to rent.

Elaborate on the energy, water, and HVAC technology that you’ve incorporated into this headquarters.

Harlan Kelly: It’s a Class A building with 13 stories, about 277,000 square feet, and about 900 employees. It features the latest in water and power efficiency, sustainable water and power design. 

We have integrated solar arrays to generate about 227,000 kilowatts a year, which represents about 7 percent of the energy needs of the building. We also have a state-of-the-art raised floor system for ventilation that allows us easy access to our building telecommunication and data lines, as well as allows employees to customize the amount of air flow in their workspace. Altogether HVAC efficiencies reduce the heating, cooling, and ventilation energy costs by about 51 percent.

What’s also really cool is that we’ve maximized daylight harvesting throughout the building, allowing us to minimize the use of artificial lighting. The system ties into other systems in the building—so at different times of day, our external shades are adjusted to reduce thermal gain, keeping the building cooler. When we have a lot of natural light, the interior lights go down. It’s a really smart building in terms of energy.

The building is just as spectacular on the water side: We use about 60 percent less water than an office building of a similar size. We first considered waterless urinals, but the ongoing maintenance and disposal of cartridges turned us off to the idea. We decided to use reclaimed water. We found a technology called the “Living Machine” that reclaims and treats all the building’s wastewater onsite through a mimicked biological wetlands, to satisfy about 100 percent of our water needs for our low-flow toilets and urinals. The system treats about 5,000 gallons of wastewater per day. That helps us reduce consumption from 12 gallons a day for a similar-sized office building to 4 gallons per day in usage. The building even has a 25,000-gallon cistern to harvest rainwater.

Before assuming leadership of the SFPUC, you spent many years as city engineer and also helped the SFPUC build the multibillion-dollar water system from Hetch-Hetchy to the city. Given that you’ve seen a lot, what’s evolved from the beginning of your career to this building you now occupy, in the way of technologies and sustainability?

Harlan Kelly: I’ve been with the city for 32 years. When I was city engineer under Willie Brown, there was a push to build as many facilities as possible, because there was a lot of need and the economy was doing well. 

I was so fortunate to work on some spectacular buildings, including our headquarters. City Hall was one where we pioneered the concept of a smart, adaptable building. We put in infrastructure to allow for conduit fiber, and put base isolators and a moat underneath the building for seismic reliability. 

The next project I worked on was Moscone West, our convention facility. That one, too, has base isolators, as does our 911 facility. We looked at making these buildings robust because of where we live in California. We wanted to have them upgraded to withstand a seismic event of a certain size.  Part of sustainability is making sure your buildings are still standing.

When you consider 525 Golden Gate, we looked at every aspect of the building to see how we could make it the greenest, because we’re all about the environment. We’re the only agency that has a community benefit policy and an environmental justice policy. We wanted this building to reflect who we are: an agency that cares about people just as much as the services we provide. 

I want to point out the way we constructed the building, which highlights this: 40 percent of the construction work was performed by San Francisco residents. That’s unheard of. We are proud that we were able to contract in that way and invest back in our city. 

Let’s return to the seismic challenge of California and San Francisco. Elaborate on the high-performance seismic design features of the building.

Harlan Kelly: We worked with a company, Tipping Mar, to come up with the concept of vertical post-tension. Typically you would use steel for structural rigidity but we used post-tension columns, which, at that time, weren’t being frequently used in the industry. Those changes helped us reduce the beam size needed on each floor, which reduced the height of the building and significantly brought down the cost. 

Normally your horizontal slabs are post-tension so that they can span a long length without having problems. With vertical post-tension, when an earthquake happens, it acts like a suspension bridge—it sways back and forth. If you had steel, that type of motion would deform the steel and the building would be rendered useless—you would have to tear it down. Our building operates like a tuning fork. It moves back and forth, and then it comes back into place after the shaking has stopped. 

You mentioned that the building has received LEED Platinum certification. Talk about what that standard requires now, how it’s evolving, and how the policies or building standards are evolving in San Francisco.

Harlan Kelly: The city itself now wants LEED Gold for any new building. That is the minimum. 

The type of material we’ve used is special. We used concrete replacement mixture that uses about 50 percent slag and fly ash, which are the byproducts of coal and steel. We took waste and made it into a recycled material for building design.  There were some issues and it took longer for it to come to strength, but the slag and fly ash had the benefit of making the concrete look kind of white, which actually goes with the whole look of the building and helps with lighting. 

Our building truly is a showcase. As you approach trying to get a LEED Platinum certification, you’ve got to look at using a lot of natural materials. You try to eliminate putting sheet rock up, and use exposed steel beams and columns. We looked at locally sourced materials like granite and terrazzo stone. Even our carpet uses recycled materials.

Tyrone Jue: I’d also like to highlight one thing about the “Living Machine” and the recycling system we have here on site. We have the first permit for an onsite non-potable system located within a building. 

This building became a model, and then Harlan worked with our Board of Supervisors to get an ordinance passed to help streamline the process for the entire city. Now, buildings across San Francisco can implement similar types of technology so that they can use that non-potable resource available to them onsite for flushing purposes or irrigation. 

Harlan Kelly: And that applies even to sharing these resources outside the building. For example, if a building is next to a park or a plaza, you should be able to use that reclaimed water for irrigation. 

In our headquarters, it turns out our water use is so low that we don’t have a lot of excess water to use for irrigation across the street at the plaza in front of City Hall.

Often when other developers and cities are challenged to go for a LEED Platinum standard, they question the cost of that effort and the return on investment. You’ve suggested that the SFPUC has saved money. Elaborate on the cost structure of doing the right thing.

Harlan Kelly: We were fortunate to have done it during the last recession, when there was a huge downturn in construction work. Even our capital projects benefited. We came out with a lot of our water system improvement programs right after the China Olympics, when steel prices dropped dramatically. We were the only game in town putting out these large projects, and bids were undercutting our engineering estimates by up to 40 percent.  That’s when we saw that there might be an opportunity to make this green headquarters work within our budget.

Also the creativity of the design team in coming up with this post-tension concrete vertical structure approach saved a lot of money. 

The total construction cost of the 277,000-square-foot building was about $146.5 million. That’s roughly $500/square foot. The construction cost at that time was very reasonable. 

Now it’s really expensive to do these same things. People are busy and the cost of construction went up, especially here. 

Last year at VerdeXchange 2015, you spoke about the evolution of “One Water.” The governor has been up front on pressing the drought and reactions to the need for water conservation. How is the SFPUC planning to address El Niño while at the same time continuing its conservation and “One Water” strategies?

On the water side, we’re looking at diversifying our water supply. We’re looking at groundwater. We’re actually building new wells on the west side of San Francisco that will blend well water with our Hetch Hetchy water. 

We’re also partnering regionally with other Bay Area cities to manage our water supplies better through conjunctive use.  During a wet year where we have plenty of water, we’ll provide more surface water and ask certain customers not to use their groundwater. This will allow the groundwater storage levels to replenish. Then in dry years, they’ll use more of their groundwater, which will stretch our Hetch Hetchy surface supplies. We’re asking them to store water for the future.

We’re expanding our recycled water use. We’ll begin construction soon on a new facility located at our Oceanside Wastewater Treatment Plant, near the San Francisco Zoo. We’re going to put a reverse osmosis system in there primarily for irrigation use. Then we’ll run the reclaimed water to Golden Gate Park and other golf courses for irrigation. 

Hopefully this year is a wet one, because our system is based on storage. We have this whole system of reservoirs and a water bank. We’ve been so fortunate to have this amazing Hetch Hetchy Regional Water system, but our overall storage levels continue to decrease due to the drought. If the drought continues, it will hurt the water supply that we use to meet all of our 2.6 million customers’ needs. If we do have a wet year, we’ll be able to replenish our supplies.  If we get heavy snow that’ll be really great. We depend on not only rain, but like most in the state, we also depend on snow as a form of storage. We in some ways prefer more snow than rain.

On the flip side, we’re very concerned about the rain intensity, because we also manage the sewer system. We have experienced localized flooding during extreme storms, which understandably frustrates the neighbors and communities. They feel that our sewer systems should minimize the flooding. There’s a lot of education right now about how our system is built to manage a certain size storm. Anything above that, and low-lying areas will be flooded. We’re trying to convince residents to prepare and get flood insurance. But just try to have that dialogue when there’s a drought! 

The question is, what do you do with the water that comes in and exceeds your capacity? We started looking at green infrastructure to help alleviate some of the water rushing into our combined sewer system. 

Thinking about One Water, we have to take all of these factors into account from the rain, the snow, drinking water, and sewer systems.  

We’re going to take a serious look at placing another reverse osmosis recycling plant at our southeast wastewater treatment plant. I don’t think we’re where San Diego is—meaning, we’re not going to use recycled water as drinking water—yet. Our Hetch Hetchy water is so pure, and everyone is so proud of it, that we get a lot of grief even blending it with additional groundwater. I think indirect reuse is the future, though, but it will take time to get to that point. 

In San Francisco we’re in charge not only of the domestic water supply system, but also of the firefighting water supply system, which is a separate high-pressure system. We have high-pressure systems and then cisterns where there are vessels of standing water under different intersections. Those could be a great candidates for recycled water. We probably need to look at that, but it’s been challenging because even our firefighters have concerns about using recycled water. It would make perfect sense, though. 

We have a lot of great ideas about utilizing water multiple times. It’s a real shame to discharge fresh water into saltwater in the sea or ocean. It’s a lost opportunity.