The Cincinnati Zoo & Botanical Garden has been dedicated to the conservation of plants and animals since 1875. Proclaimed the “Greenest Zoo in America” in 2010, the Zoo has continued to lead the way in sustainability and green initiatives by greening its daily operations and reducing its impact on the environment. Through green building, solid waste management, renewable energy, water conservation, storm water management, energy efficiency and community outreach, the Zoo has strengthened its sustainability program to have a positive impact on the planet.

The Cincinnati Zoo & Botanical Garden has saved one 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. It is truly a valuable resource, one of the most importance resources on Earth. The Cincinnati Zoo is a major user of water in the city. With an award winning botanical garden and animals like polar bears, elephants and manatees, it is easy to see why the Cincinnati Zoo is a major user of water in the city. 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 74 million gallons by the end of 2012 and used even less, 52 million, last year. This reduction in water waste and consumption has saved the Zoo 5.5 million dollars on its water bills; money that’s being reinvested in the Zoo’s infrastructure. 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 in an effort to reduce storm water runoff.  The tanks keep 15 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 percent of its property off of Cincinnati’s storm water grid.

Pervious Pavement

Pervious Pavement: In cities like Cincinnati, up to 30 percent of the land surface is covered with pavement, giving us places walk, drive and park. However, when it rains, all that pavement causes water to run off of 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 stormwater 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. Read this fact sheet to learn more about “Pervious Pavement: When it Rains, It Drains” 

Green Roofs

Green Roofs: Instead of covering a roof with shingles, why not top it with living plants? That is exactly what a green roof is! Growing a green roof has many advantages, especially reducing stormwater 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 as well as taking in carbon dioxide from the air and releases oxygen. A common plant used with green roods 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 increases 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! A sample of a green roof is houses in the Go Green Garden exhibit allows you to see up close what a green roof is planted with.

Learn More: To find out more about green roofs, read “What’s Up with Green Roofs?”, and visit our Green Tips page. 

Rain Gardens

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.

At the Zoo, rain gardens can be found at the Go Green Garden exhibit, in front of the Harold C. Schott Education Center and in the Vine Street Parking Lot. The Zoo has some of the most visible and diverse rain gardens in the region, providing a model for other institutions. The information from these test gardens will help determine the best practices for creating other rain gardens in our area.

Learn More: Visit our Green Tips page to find out how to grow your own rain garden and build your own rain barrel: “Filling up with Rain Barrel Knowledge”

Renewable Energy

Wind Energy

Wind Energy – Wind energy is the fastest-growing and least expensive energy source. It is also one of the least expensive. The way wind energy, or power, works is pretty simple. The sun shines, creating wind as the air warms and rises. Like a helicopter seed blowing in the breeze, the blades of a turbine spin round in the wind, which powers a generator to produce clean energy.

At the Zoo, a 1.2kW wind turbine is installed in the Go Green Garden Exhibit. In 11 mph average winds, it can produce enough energy to run your dishwasher and refrigerator for an entire year (2000 kilowatt hours). Our Windspire wind turbine, along with the solar panels in the Go Green Garden, are meeting approximately one third of all of the power demands for the Membership and Ticketing Building. Learn More: Windspire wind turbines are being used by homes, schools & businesses. Visit our Green Tips page to find out more about how you can utilize this free energy source; also read “Working with Wind“.

Solar Energy

Solar Energy – 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 like burning fossil fuels does. 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 a become a regular sight. ti Zoo. 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, along with the wind turbine, are providing more than a third of the power demands of the Membership and Ticketing Building. The latest solar panel project, a 1.56 megawatt array with 6,400 panels installed on a canopy structure will greet guests as they arrive in the Vine Street Parking Lot. This solar array is the largest, urban, publicly accessible array in the nation. For more information on this latest solar project, visit the Solar Power page.

Melink Solar Canopy

See how much energy is being generated by our solar canopy right now!! Click here to view.

Watch this video to learn about the solar panels that you will park under when you visit the Cincinnati Zoo & Botanical Garden:

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; “The Scoop on Solar Panels”

Geothermal Energy

Geothermal EnergyGeothermal 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 geothermal 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, and “Gearing Up with Geothermal Energy”.

Biomass 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, and “Benefits of Biomass” fact sheet.

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 of 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 5 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 been able to drastically reduce 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! With a population as large as the United States, just imagine what that would be equivalent to. What is happening to all of 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

Dumpster Diving & Baseline Data: In order to truly understand what needs to happen to reach a zero landfill status, we first must 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 there is still room to grow, and really help our staff and our visitors reach this zero landfill goal. 


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 is composted every week. When our composting program began in 2011, 3 main herbivore exhibits were composting all of their food scraps, bedding and animal waste. Now, almost every area within the Zoo is composting in some way. In 2012, almost 592 tons of organic waste was diverted from entering the landfill.

Learn More: Learn how easy it is to compost in your own backyard by visiting our Green Tips page, and “Crazy About Composting” fact sheet.


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 cloth bags for transmitting cash rather than plastic bags. We recognize that the best way to reduce waste is to not create it in the first place.

Learn More: To find out more about recycling in Cincinnati, visit the Green Tips page, and “Ready, Set, Recycle!”.


SSA: Our food and retail partner, Service, Systems, Associates, or SSA, is just as committed to conservation and sustainability as we are. They have invested in compostable material for almost everything served in the Café, including all plates, bowls, cups and cutlery. Cardboard, plastic bottles and aluminum cans are recycled. SSA is also enrolled in the TerraCycle Program, which allows us to collect chip bags and candy wrappers that will be upcycled and turned into products such as wallets, bags and purses. SSA is ensuring that behind the scenes, all food scraps for meal preparations are composted, and every recyclable item placed in a recycling bin. They are currently working towards a 4-star rating for green restaurant certification through the Green Restaurant Association (GRA, which is the highest rating a restaurant can achieve. A portion of the green certification depends on reducing waste. 

YOU and the Zoo

YOU and the Zoo: Our guests are an important part of the success of our Zero Landfill commitment. When the Zoo Café re-opens this Spring, 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! Any food waste, paper napkins, juice boxes and milk cartons can go in the compost bin. Reduce your waste even more 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!

Learn More: To find out how your school can reduce waste in your community, participate in the Zero Landfill Challenge

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 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 the majority of 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 – anticipated LEED Platinum

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, and the fact sheet “Green Building, Give it a Go!”.

Living Building Challenge

 lbcpainteddogThe Cincinnati Zoo is pursuing its most ambitious challenge in sustainable construction yet: the Living Building Challenge for the African painted dog exhibit in Africa. 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 would make the African Painted Dog Exhibit would one of the Greenest Facilities in the Country! Click here to learn more about this exciting project!