The Cincinnati Zoo & Botanical Garden has saved two BILLION gallons of water, enough to provide water (indoor and outdoor use) for 10,000 households for a year, since 2006 when it launched a major initiative to reduce water usage! The Cincinnati Zoo recognizes the importance of conserving water. Even though two-thirds of the Earth’s surface is covered in water, only a tiny percentage of it is available as clean, fresh water. With an award-winning botanical garden and animals like little penguins, hippos, and manatees, it is easy to see why the Cincinnati Zoo is a major user of water in the city. Overall, our use of potable water from the city is down 80% from 2005.

Official Water Sustainability Sponsor

By aggressively fixing leaks in exhibit pools, installing low-flow faucets and fixtures, upgrading filtration systems and changing everyday behaviors, the Zoo brought the 2005 figure of 220 million gallons, enough water to fill around 335 Olympic sized swimming pools, down to 49 million gallons in 2016. This reduction in water consumption has saved the Zoo 10 million dollars on its water bills; money that’s being reinvested in the Zoo’s infrastructure.

Once being the largest consumer of city water, the Cincinnati Zoo &Botanical Garden has succeeded in cutting their water use in half, twice. Through 15 years of strategic planning and design, efforts have saved over half a million dollars and dramatically reduced the environmental footprint, without compromising the health and wellness of our plants and animals.

We have 500,000 gallons of stormwater tank capacity. And Elephant Trek will be adding another 1 million gallons to this number! That would be like 100 swimming pools full of water! The Elephant Trek reservoir will be online in 2024 and will feed all of Elephant Trek, but also Manatee, Jungle Trails, the Veldt, and many other exhibits

These tanks provide water used for:

  • Fiona’s pool
  • African Penguin
  • Little Blue Penguin
  • Lion moat
  • African Savannah moat
  • Cheetah moat
  • Painted dog
  • Future North America habitats
  • Irrigation
  • Used for hosing and cleaning of animal bedrooms

Cincinnati’s sewer system, a combined sewer overflow (CSO), is the oldest in the country. Due to the age and capacity of the system, heavy rain events cause billions of gallons of raw sewage to surge into the Ohio River, one of the most polluted rivers in the country. Metropolitan Sewer District (MSD) fully funded the tanks under Africa to reduce storm water runoff.  The tanks keep 13 million gallons of water out of the sewer system annually! The Zoo’s groundbreaking water management system helps keep polluted overflow from people’s basements and the Ohio River. Diverting water from the sewer system has saved tax payers money by reducing issues caused by flooding, erosion and pollution.  Eventually the Zoo hopes to get 100% of its property off Cincinnati’s storm water grid.

Hippo Cove, with a pool of 67,000 gallons of reclaimed rainwater, uses the most advanced life support system at the Zoo. Hippos can spend up to 16 hours a day in the water, so filters work constantly to keep Henry and Bibi’s habitat clean and comfortable. Pushing water through the filtration system at 1,800 gallons per minute (7.5 times more than a fire hose), visitors can expect to see our hippos in crystal clear waters.

Pervious Pavement

In cities like Cincinnati, up to 30 percent of the land surface is covered with pavement, giving us places to walk, drive and park. However, when it rains, all that pavement causes water to run off roads and parking lots into sewer drains, contributing to flooding and pollution. Unlike traditional pavement, pervious pavement that allow rainwater to seep through it, instead of forcing water off the edges into sewer systems. Tiny holes in pervious concrete or spaces between pervious pavers allow water to pass through, recharging our groundwater system or saved to be reused later.

At the Zoo, more than 30,000 square feet of pervious pavement allows thousands of gallons of storm water to be stored at a time.

Learn More: Visit our Green Tips page to find out more about using pervious pavement in your own home.

Green Roofs

Instead of covering a roof with shingles, why not top it with living plants as a green roof? Growing a green roof has many advantages, especially reducing storm water runoff, retaining up to 75 percent of rainwater instead of allowing it to drain through the sewers. The plants on a green roof are very busy filtering out pollutants & taking in carbon dioxide from the air to release as oxygen. A common plant used with green roofs is sedum, a very water thirsty and drought resistant plant. And because these plants are covering the roof, they are reducing the urban heat island effect by retaining heat, rather than absorbing the sun’s energy and re-emitting it as heat. This urban heat island effect causes cities to be up to 7 degrees hotter than rural areas. A green roof can insulate your home from heat, cold and sound as well as increase the lifespan of the roof by two or three times. They are very easy to care for and create a beautiful habitat for local wildlife.

At the Zoo, a 2,400-square foot green roof grows on top of Giraffe Ridge Barn. This green roof is a test garden, planted with a variety of sedum and other plants. The Primate Center is also topped with a green roof, including a variety of plants, bushes, even trees!

Rain Gardens

In a rain garden, water thirsty plants are grown in a low spot designed to temporarily collect rainwater from downspouts and pavement. This strategic placement of a garden helps reduce storm water runoff, pollution, erosion and flooding. A rain garden also purifies the fallen rainwater as the root systems of the plants filter out dirt and other particles before releasing it deeper into the soil. Like other gardens, a rain garden provides a beautiful landscape as well as a good habitat for wildlife.

Learn More: Visit our Green Tips page to find out how to grow your own rain garden and build your own rain barrel

The Zoo participates in the Rain Barrel Auction each year! Learn more. 

Renewable Energy

Cincinnati Zoo & Botanical Garden has made a commitment to using clean, renewable energy, as well as producing our own renewable energy on site.

Solar Energy

Despite adding 12% in building square footage, we have reduced our reliance on grid-based electricity by 23%.

What do green leaves, alligator scales, and solar panels have in common? They all harness the sun’s energy! Green leaves use the sun’s energy to make food. Crocodile scales harness the sun’s energy to stay warm. Solar panels convert sunlight into electricity. Solar, or photovoltaic, cells are made of silicon, a semi-conducting element. These cells absorb sunlight and convert it into electricity without releasing carbon dioxide into the air. Carbon dioxide is the primary culprit of climate change, which is already threatening wildlife and their habitats around the world. Not only is solar energy clean, it comes from an unlimited, renewable, and free resource. Generating solar energy reduces our dependence on fossil fuels, which are limited, non-renewable, and costly.

At the Zoo, solar panels have become a regular sight. A 20kw solar array adorns the roof of the Harold C. Schott Education Center, providing up to 25 percent of the energy needs to operate the building. 10kw solar panels are at the Go Green Garden Exhibit. These panels are providing more than a third of the power demands of the Membership and Ticketing Building. The 1.56 megawatt array with 6,400 panels installed on a canopy structure greets guests as they arrive in the Vine Street Parking Lot. This solar array is the largest, urban, publicly accessible array in the nation. Solar panels are also found at the Zoo’s Erkenbrecher parking lot, Rockdale Academy, and the electric train!

Not only do the solar panels have aesthetic, structural, and educational benefits, but the1.56MW array can:

  • reduce 1,775 tons of annual CO2emissions by replacing coal-fired power
  • power 200 homes per year
  • provide 30% of the Zoo’s current energy needs
  • generate 100% of our energy needs, onexceptionally sunny, cool days, even sending extra power back to the utility company

Learn More: Visit our Green Tips page to learn how you can harness the clean, renewable and free energy of the sun to heat and power your home

Geothermal Energy

Geothermal energy comes from the natural heat of the Earth, and can be used to generate electricity or heat and cool buildings without burning fossil fuels and accelerating climate change. To produce electricity from heat radiating from the center of the Earth, wells are drilled and water is pumped through pipes hundreds or thousands of feet into the ground. There the heat turns water into steam. As it returns to the surface, the force of the steam turns the turbines to create electricity. Geothermal energy can also naturally heat and cool buildings. Geothermal heat pumps, which use very little electricity, circulate water though a continuous loop of piping that goes just several feet underground where the temperature is about 55 degrees F° all year-round. In winter, the water picks up the heat in the earth and carries it back to the geothermal heat pump which heats the building. In summer, the water picks up heat from the building and takes it underground, thus cooling the building.

At the Zoo, 36 geothermal wells use this heat transfer to contribute significantly to the heating and cooling of the buildings located in Historic Vine Street Village.

Learn More: Visit the Green Tips Pages to learn more about harnessing geothermal energy.

Biomass Energy

Biomass energy is harvested from organic materials made from plants and animals that contain stored energy from the sun. These materials include wood, crops, manure and other organic waste. Biomass can be converted into usable forms of energy such as methane gas (released from rotting garbage and animal waste) or transportation fuels such as ethanol and biodiesel.

At the Zoo, several options related to biomass energy are being explored, including a small scale anaerobic digester that will generate energy from elephant waste. The train and other diesel vehicles use biodiesel.

Learn More: To find out more about biomass energy, visit our Green Tips pages

Energy Efficiency

Electricity in the United States accounts for 38 percent of carbon dioxide emissions produced. This includes the energy used in our homes, schools and businesses. All this energy used contributes to pollution, global climate change and the depletion of our natural resources. The Cincinnati Zoo recognizes the importance of energy efficiency, and is committed to reducing our use as much as possible. In the past 7 years, despite adding 25 percent more building square footage, the Zoo has reduced their energy usage by 11 percent. Not only does this reduction help lower the Zoo’s overall carbon footprint, it has also saved over $1.5 million on utility bills. The Zoo has drastically reduced its energy usage by taking a number of different steps, including:

  • Upgrading to energy efficient light fixtures to energy efficient ones, as well as placing them on motion sensors so the lights automatically turn off when no one is in the room
  • Replacing old equipment and appliances with more efficient boilers, furnaces, water heaters, refrigerators and freezers
  • Unplugging any equipment that was not in use on a regular basis
  • Using heating, ventilating and cooling systems that employ energy management equipment and software
  • Harnessing renewable energy through solar panels, geothermal wells, a wind turbine and biomass
  • Switching incandescent lights to LED lights for our Festival of Lights, reducing energy usage by 75 percent

Learn More: Find out how you can join the Zoo in reducing your energy use at home. Visit our Green Tips page for tips and resources on energy efficiency.

Worm Composting

The average American generates about 4.5 pounds of garbage per day. That is equal to 1,643 lbs of solid waste every year! What is happening to all that garbage? About one-third is recycled, while the rest is sent to landfills, burned in combustors or finds its way into the natural environment. The Cincinnati Zoo is committed to diverting as much waste as possible from the landfill, either by making less waste in the first place, or through composting and recycling waste. In 2012, we made the commitment towards becoming a zero-landfill facility. This means that less than 1% of our total waste stream will be sent to the landfill.

Dumpster Diving & Baseline Data: To truly understand what needs to happen to reach a zero-landfill status, we must first learn and understand the waste habits of our visitors and employees. Through a series of dumpster dives, Zoo employees – including executive directors – and volunteers sorted through tons of the Zoo’s trash to record what was being thrown away, and what could have been diverted from the landfill in some way.  We learned that about 80% of what was heading to the landfill could have been recycled, composted or donated. Items like paper, plastic bottles, brush and yard scraps, leather work gloves and packaged food were found. Almost 12 tons of waste was sorted through between 2 different dives. The good part is that we still have room to grow, and believe that our staff and our visitors can work together to reach our zero-landfill goal.

Plastic Free

Plastic Bags Have Gone Extinct

GoGreen1-300x173We are Plastic Bag & Straw Free as part of our ongoing Green initiative.

Did you know?  The world is facing at Plastic Bag Pandemic:

  • Over 1 trillion plastic bags are used every year worldwide.
  • About 2 million plastic bags are used every minute around the world.
  • Americans use and throw away 100 billion plastic bags every year.
  • Only 3-5% of plastic bags get recycled.
  • The average American family takes home 1,500 plastic bags a year.

Bring Your Own Bag: Do you part for the planet and bring your own reusable bag or purchase your Zoo-themed reusable tote from the gift shop for only $1.99. Thank you for helping us be the #GreenestZooInAmerica!


Composting: Yard trimmings and food scraps make up about 25 percent of the trash produced in the United States. Why throw all that waste away and take up landfill space when it can be composted into nutrient rich, organic material for your garden? Composting is nature’s way of recycling!

At the Zoo, more than 8 tons of organic material can be composted every week. When our composting program began in 2011, 3 main herbivore exhibits were composting all their food scraps, bedding and animal waste. This grew to almost every area within the Zoo composting in some way. In 2012, almost 592 tons of organic waste was diverted from entering the landfill. In July 2014, our composting partnership ended, and we are currently in search of a new compost plan!

An aerobic bio-digester was installed at the Zoo in 2021. The digester will convert food waste and poo from elephants, rhinos, zebras, and even Fiona, into a beautiful fertilizer that can then be used to breathe new life into our botanical garden, community gardens, and your garden.

Learn More: Learn how easy it is to compost in your own backyard by visiting our Green Tips page

Zero Waste

The Cincinnati Zoo & Botanical Garden’s Sustainability team was awarded a Recycle Ohio EPA grant to acquire equipment for our award-winning Horticulture team. The Cincinnati Zoo’s Green Waste Recycling Program (GWRP) was put in place as part of our Zero-Waste initiatives, to process horticultural waste and debris into value-add mulching products to be used in our gardens and community projects.

The purpose of this award was to further the GWRP and supply the Horticulture team with a towable Bandit Model 1425 Mini Beast horizontal grinder. This machine reduces green waste volume by 75% or more by processing bamboo stalks, elephant grass, tree branches, logs, herbaceous waste, woody waste, pallets, etc. This creates a readily useable product, keeps used space at a minimum, eliminates the need to haul green waste (reducing emissions and transportation costs), and can help reduce irrigation needs by offsetting some of our annual mulch purchases.

Annually, we produce about 1,080 cubic yards of green waste, accounting for about 25% of our total waste volume. Historically, we’ve managed this waste through large, on-site mulching piles or, in special cases, through third-party hauling to off-site mulching facilities. However, with the development of new animal habitats, we no longer have the space for large on-site piles.

The Cincinnati Zoo piloted the Mini Beast and it proved to be successful at processing nearly all the waste that we trialed as input, including bamboo stalks, elephant grass, tree branches, logs, herbaceous waste, woody waste, pallets, etc. We processed about 60 cubic yards of waste in roughly 4 hours. We observed a volume reduction rate of about 75%. With the use of the 2”-round screen, we were able to produce a mulch much finer than our purchased mulch. We were very pleased with the performance and versatility of the Mini Beast and finalized its keystone role in the GWRP!


Recycling: Recycling may be one of the easiest of the three “R’s”. But reducing and reusing are just as important for diverting trash from entering the landfill. The best way to deal with trash is to make less of it in the first place.

At the Zoo,  a recycling bin always accompanies a trash bin. This makes it easy and convenient for guests to recycle plastic bottles and aluminum cans. Other items like cardboard, batteries, electronics, plastic bags, and light bulbs are also recycled rather than thrown in to the trash. We are the #1 zoo in the country that recycles cell phones. Many Zoo animals receive enrichment items made from cereal boxes, old, clean blankets and sheets, cardboard tubes, even kitty litter buckets, giving these items a second or third use. Our green purchasing policy has been put into place so that we are only purchasing items that are sustainable, which means they are made with recycled content, or are a product that can be recycled, reused or composted as much as possible. We have also looked at items around the Zoo that can be replaced with a more sustainable option, such as pledging to no longer use plastic bags in the gift shop.

Learn More: To find out more about recycling in Cincinnati, visit the Green Tips page


SSA: Our food and retail partner, Service, Systems, Associates, or SSA, is just as committed to conservation and sustainability as we are. Cardboard, plastic bottles and aluminum cans are recycled. Base Camp Café was awarded a  4-star rating for green restaurant certification through the Green Restaurant Association (GRA), the highest rating a restaurant can achieve.

Working with the Green Restaurant Association (GRA), we have designed and maintained both of our on-campus restaurants to achieve the highest certification for sustainable food-service practices, 4-Star GRA Certified

Taste Catering at the Cincinnati Zoo is proud to support local business, agriculture and sustainability efforts within our operation. We support over 30 local businesses and farmers regionally located to Cincinnati. By working with other organizations that share our sustainability initiatives, we bring you products that are grown, raised and farmed responsibly. Look for our Taste Local identifier throughout our menus and know that you are not just supporting the Zoo, but also local businesses and the environment.

YOU and the Zoo

YOU and the Zoo: Our guests are an important part of the success of our Zero Landfill commitment. When the Base Camp Café opened in 2013, full composting, recycling and landfill bins will be available for tossing your trash. SSA has worked hard to make almost everything that they sell in the Café either compostable or recyclable. Check out the signs or ask a staff member for instructions on which bin the waste from your meal should go. If you brought food from home to enjoy, most of it can be composted as well! Reduce your waste by using reusable containers instead of plastic bags to pack snacks and sandwiches. Place any empty plastic bottle in the recycling bin. Chip bags and candy wrappers can be placed in the Teracycle bin. Ideally, nothing will go in the landfill bin. Thank you for supporting our Zero Landfill Initiative!

In the United States, buildings are the main contributor to our carbon footprint, from electricity, water, materials used in the building as well as where the building is located. Green building is an eco-friendly way to construct structures, using processes that are environmentally responsible as well as being resource-efficient not only during construction, but through the entire life of the building. The U.S. Green Building Council has developed a rating system that is an industry-recognized, voluntary standard for sustainable building design. This rating system is the Leadership in Energy and Environmental Design rating system, or LEED, and has four levels of certification – Certified, Silver, Gold and Platinum.

At the Zoo, we recognize that most an organization’s carbon footprint lies in its buildings and utilities. Because of this, the Zoo is committed to building all new projects to LEED Silver standards, the first Zoo in the country to make this commitment publicly.

The Zoo currently has more LEED buildings than any other Zoo in the nation, with three more projects underway:

  • Harold C. Schott Education Center – LEED Silver, 2006
  • Historic Vine Street Village – LEED Platinum, 2009
  • Zoo Pavilion – LEED Gold, 2009
  • Zoo Gift Shop – LEED Gold, 2010
  • Cat Canyon – LEED Gold, 2012
  • Shipping & Receiving – LEED Silver, 2012
  • African Savannah – LEED Gold, 2016
  • Hippo Cove – LEED Platinum, 2017
  • Gorilla World— LEED Platinum 2018
  • Roo Valley – LEED Platinum 2021

All the materials used to build each of our LEED projects are sustainable as possible. Some features of these projects include no or low VOC paint, bamboo flooring, 100% recycled carpet, strawboard countertops, recycled steel, recycled drywall and plastic lumber. The Zoo has also gone through existing buildings to green them up as much as possible.

Learn More: Find out how you can incorporate green building into your new or existing home. Visit our Green Tips page to learn more

Living Building Challenge

lbcpainteddogThe Cincinnati Zoo achieved Living Building Challenge (LBC) Certification for Painted Dog Valley. The Living Building Challenge is a non-profit, international building certification program that promotes the most advanced measurement of sustainability for building and construction projects. This makes the African Painted Dog Exhibit would one of the Greenest Facilities in the Country! Click here to learn more about our certification announcement.

A Commitment to Net Zero Energy, Water and Waste:

As part of the ambitious More Home to Roam capital campaign, the Zoo is taking their groundbreaking, robust storm water management program to the next level to drive down non-potable water use to zero.  By capturing 100% of the storm water and reusing it in the habitats, the Zoo can divert the water out of the city’s combined sewer system.  The Zoo will also focus on being net zero energy by driving efficiencies throughout the existing systems and pursuing advanced energy options including solar, wind and biomass.  And, with proper organic waste management, the Zoo will strive to become a net zero waste facility.


Simply put, “net-zero” refers to an overall balance between emissions produced and emissions taken out of/prevented from entering the atmosphere. To define the goal of becoming net-zero, the CZBG team determined that the pillars of ENERGY, WATER, and WASTE are the most applicable, achievable, and impactful on which to focus design and retrofit priorities. Because of the unique and precious contents of our institution, there will certainly be regulatory and logistical obstacles, and some projects will be much higher-hanging fruit than others. But, the end-goal of achieving net-zero operations is unquestionably worth our commitment. Our global perspective and motivation for becoming anet zero facility are about reducing our heavy, institutional carbon footprint to zero and showing that, by strategically dedicating resources and skills, it can, and should, be done by other facilities across the globe.