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Executive interview with Brian Good, Denver Water

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Executive interview with Brian Good, Denver Water
Brian D. Good (photo courtesy Denver Water)

Denver Water is a water utility with hydropower installed at many locations in the system to offset operating costs. In this interview, Brian D. Good discusses the integration of water and power and the importance of using water sustainably.

Brian D. Good is chief administrative officer of Denver Water, the largest and oldest water utility in the U.S. state of Colorado. He leads a diverse team of people focused around safety, security, emergency management, environmental compliance, sustainability, purchasing, contract control, records and printing, Geographic Information Systems (GIS) and recreation at Denver Water facilities.

As part of its water supply system, Denver Water operates seven hydroelectric power plants to offset operating costs, typically saving ratepayers about $4 million per year. Renewable energy, including hydroelectric generation and solar photovoltaic systems, is in place at nine of Denver Water’s facilities, with 26.8 MW of capacity and average production of 60,000 MWh.

The company is a HYDROVISION International 2022 host utility, and Good will speak during the Utility Executive Roundtable at that event on Thursday, July 14. In this interview, Good provides insight into the company’s system, how hydropower contributes to water deliveries, and the future of its hydro facilities.

Q: Please give our readers an overview of Denver Water, including your hydroelectric portfolio.

Good: Denver Water was founded in 1918 under the Denver City charter. We are part of the City and County of Denver but a separate enterprise governed by a five-member board appointed by the mayor. We serve approximately 1.5 million people, about half of whom are in Denver and the other half in the areas surrounding the city.

All of Denver’s water supply comes from surface water, primarily snow. We capture water in the Rocky Mountains as snow melts, and we store it until it is needed. Because our reservoirs are much higher in elevation than Denver is, we take advantage of gravity and generate hydropower at several locations as water is released to our treatment plants. Those treatment plants also use gravity to deliver a substantial amount of water to our service area, so we can generate more hydropower with treated drinking water. Depending on how the water flows, some water passes through three hydropower turbines before reaching our customers’ taps.

Denver Water currently has 25.5 MW of hydropower capacity.

Q: I know Denver Water is Colorado’s oldest water utility. How does hydropower support that primary function?

Good: Energy created by our hydro units is used behind the meter to power some of our facilities, with excess energy sold to local utilities. The use and sale of that hydropower offsets our expenses and helps keep rates lower for our customers. Over the past 10 years, we have voluntarily tracked and reported our carbon emissions, and hydropower generation reduces our carbon footprint. Some may wonder why this is important. At Denver Water, we know that our mission – delivering safe drinking water – is inextricably linked to the environment. We need to do our part to protect the environment so there is a sustainable water supply for our customers going forward.

Q: You’ve been with Denver Water for more than 21 years. What accomplishment are you most proud of?

Good: Great question. Honestly, it doesn’t feel like 21 years. I still jump out of bed every day ready to serve our customers and excited to solve the challenges of today and tomorrow. It is an honor to work with an incredible team of professionals.

While I’m proud of what we do on a daily basis, a couple of projects have been really special. In 2002, I was hired as the first supervisor of our 30-million-gallon-per-day (capacity) water recycling plant, a facility that takes treated wastewater, purifies it even further, and distributes it to customers for irrigation and industrial uses. The Denver Zoo is one of the largest customers, and the Denver Museum of Nature and Science uses the water in heat exchangers to help heat and cool one of its buildings (like geothermal wells but requiring less infrastructure). In the arid western U.S., every drop of water is critical; too important to use just once. So, starting a plant to help us reuse water to the greatest extent possible was inspiring. It felt like I was really making a difference. In addition, we hired an incredibly diverse team to run the facility — diverse from gender, age, ethnicity and experience perspectives. The quality of discussion and ideas that group generated was remarkable. It really shows the power of bringing different people together.

A second, more recent project was assisting with redevelopment of Denver Water’s Operations Complex, a 35-acre facility that houses our trades, fleet, warehouse, meter shop, field service and administration functions. The site has been our home since the 1880s, but over the years buildings became inefficient and less safe and were not oriented for operational flow. Seven new buildings were constructed and two were remodeled to replace existing facilities. All buildings have various levels of LEED (Leadership in Energy and Environmental Design) certification, with the Administration Building certified as LEED Platinum and Net Zero Energy. It includes 1.3 MW of onsite solar power. We will also collect and treat all wastewater, reusing it for irrigation and toilet flushing. Rooftop rainwater will also be stored and used for irrigation. Along with our hydropower, this is another example of our commitment to the environment and sustainability.

Q: You recently got the go-ahead to proceed with an expansion of Gross Reservoir, which supplies a 7.6 MW hydropower facility. What is the plan there?

Good: The project will increase the hydropower capacity from 7.6 MW to 8.1 MW using the existing equipment and higher reservoir head. We do plan to add a control valve to keep the units in an optimal operating range and make small adjustments to the wicket gates and control system to facilitate that increase.

The height of Gross Dam will be raised, increasing hydroelectric power output (photo courtesy Denver Water)

More important than capacity, we expect to create 16.5% more hydroelectric power, resulting in an increase of clean energy output to the grid of about 4.4 million kWh annually.

Q: Particularly in the western U.S., reliability of the water supply is a major issue. Are you facing challenges in this area?

Good: Everyone in the western U.S. is keenly aware of and monitors short- and long-term water supply. We have promoted conservation and water efficiency since at least 1938. Today, Denver Water serves 25% of the Colorado’s population (and gross domestic product) with just 2% of the water used in the state. Over the past 20 years, our customers have reduced water use more than 22% and now use about as much water as they did in the 1970s, even though there are 600,000 more people in our service area.

That said, there is always more to do. We continue to work with the federal government, other states, fellow utilities and other water users to address water shortage in ways that sustain our way of life and protect the environment.

Q: What is the status of your other hydro projects? Is there any work going on there?

Good: We just finished servicing our Roberts Tunnel hydro. While the capacity of that unit will remain unchanged, we expect 1.5 million kWh of additional annual energy generated to increased efficiency.

All our hydro units undergo a teardown at 10- to 15-year intervals, based on operating conditions and ongoing condition monitoring.

Q: Do you see your company expanding its hydropower portfolio in the future? Through new development, rehabilitation or upgrades?

Good: We will soon upgrade our Strontia Springs Hydropower unit, and that will increase capacity from 1.1 MW to about 1.5 MW. There is no room to add additional turbines, so this is a refinement in the equipment that will improve efficiency.

The capacity of the Strontia Springs hydropower unit will be increased in the future (photo courtesy Denver Water)

A few years ago, we added a second hydropower unit at Williams Fork that allows us to generate power at very low flows. We are studying a couple of other locations, but most are remote and the cost of getting electricity from the generator to the grid is high. That said, we have had some discussions with our power providers to see if they would be interested in partnering with us. They would like to see large, pumped-hydro projects to help with our state’s zero-carbon goal and think hydro can help at the end of the day when solar begins to taper off but electric demand is still high. We have a couple of locations where pumped hydro could be viable.

However, the coolest project currently under construction is our new Northwater Treatment Plant. This facility will partially replace an older plant and has been designed to be a net energy producer. Initially, it will have a 540 kW hydro unit that will be capable of producing more than enough energy for the plant. A future unit is anticipated to add another 800 kW when the plant is expanded.

Q: You are speaking during the Utility Executive Roundtable session upcoming at HYDROVISION International. Can you give us a sneak peek into a couple of the hot topics for Denver Water that you plan to cover?

Good: The Northwater Treatment Plant hydro unit is part of an extremely sustainable facility. We anticipate that plant to be a net energy producer once it comes online.

We are also evaluating some in-pipe hydro to replace sleeve valves in our distribution system.  Two locations that look promising in the near term are our Moffat Water treatment Plant (800 kW) and Capitol Hill Valve Vault (50 kW).

Finally, over the past several years, we were part of a pilot project to test in-channel hydropower at one of our facilities. While the economics may not pencil out for a full-scale implementation yet, all the partners learned more about a cutting-edge form of hydro.

And maybe I’ll have more information about pumped hydro.