A road cuts through pristine rainforest to give a community access to the city. A dam creates a reservoir to provide freshwater to a growing town. A platform that is miles from the shoreline gives access to oil reserves deep below the ocean floor.
These are all examples of infrastructure—physical structures that provide the underpinnings for modern society. Infrastructure is a necessary part of the development associated with a growing human population, but it can also have devastating impacts on the environment. The road through the rainforest may fragment habitat or cut off the migration route for an endangered species. The dam may have diverted water from freshwater habitats already struggling through a drought. A spill from the oil platform may have killed marine organisms and left the shoreline polluted.
Environmental concerns are not always considered during the design, planning and construction of infrastructure projects. WWF works with governments, industry and other leaders to encourage the consideration of sustainability in these efforts, including examining innovative ways reduce environmental impact and protecting sensitive habitat that may be irrevocably damaged by these projects.
Only a little more than one-third of the world’s 246 longest rivers remain free-flowing, drastically reducing the diverse benefits that healthy rivers provide to people and nature everywhere, according to a new study by WWF and partners.
Infrastructure for transportation, energy projects and other developments that make modern life possible can often damage and destroy natural habitats, and negatively impact biodiversity.
Roads and Railways
Roads and railways are necessary to move goods and people across distances, but they have long-lasting effects on the landscapes they cut through. They can fragment ecosystems and halt migrating animals in their tracks. Cars and trains may kill animals in their paths and bring noise and air pollution to previously undisturbed areas. And roads and railways can facilitate illegal logging and hunting by opening up regions long kept pristine by their inaccessibility.
There are more than 45,000 large dams around the world, storing three to six times the amount of water that is naturally contained in rivers. Most have a relatively benign impact on their local environment, due to their design, location, or mitigation efforts. However, some dams have far-reaching environmental impacts, contributing to the ongoing loss in biodiversity both in the rivers themselves and in the local ecosystems. Impacts could include reducing or blocking sediment flow, hampering fish migration, flooding habitat, or increasing water pollution.
Water Transfers and Channelization
Massive engineering projects have diverted water from rivers to supply cities and irrigate farms. But while these efforts may fill immediate needs, they can have large-scale impacts. Even small amounts of water diversion can leave a river basin vulnerable to drought in times of low rainfall. Wetlands may be destroyed, threats to already vulnerable species may increase, and communities that depend on the river basin may face consequences that include their displacement.
Oil, Gas and Mining Facilities
Many environmentally sensitive areas, such as the Arctic, the Amazon and the Congo Basin, hold rich deposits of oil, gas, metals and other valuable natural resources. Developing the infrastructure required to extract these resources – including roads, rail, transmission lines and dams – can cause severe environmental damage. This includes the fragmentation and destruction of forests and other habitats, the interruption of migration routes, the draining of freshwater, and the erosion or pollution of the land.
Infrastructure development is happening fast in Gabon, Africa. New roads pose an increased threat to wildlife.
Ecosystems can be destroyed during the creation or installation of infrastructure such as roads and dams, and these structures can facilitate further destruction that continues for decades.
Habitat Degradation and Destruction
When roads pave over forests, or dams create lakes where there once were streams, plants and animals lose valuable habitat immediately. But that habitat destruction can continue long after the infrastructure is first put into place if it generates pollution or facilitates the further degradation of the landscape due to additional legal and illegal development.
Roads make it easy for people and goods to move long distances, but they also make it easier for hunters to reach animals in remote areas. Timber companies that have built roads through forests in the Congo Basin, have helped to fuel the bushmeat trade in that region and contributed to the overhunting of vulnerable species including gorillas, elephants and leopards.
More than 60% of the world’s rivers have been fragmented by dams, which can interrupt the natural flows of waterways and disrupt the movement of sediment. This increases the risk of floods and hampers navigation. Dams can also degrade water quality through increased salinity, decomposition of organic matter or the leaching of mercury from the soil, making the water unusable for drinking or irrigation. In addition, dams may prevent migratory fish from reaching their spawning and feeding sites, contributing to the ongoing loss of freshwater fish species.
Migration Routes Blocked
Many animals migrate long and short distances to find mates, food, water and other resources. Large animals need big spaces and lots of freedom to roam. But roads, fences, dams and other structures can block these wildlife corridors, fragment habitat and push species towards extinction.
Roads, dams and other infrastructure can create noise, air and water pollution that increases as development grows. In the Alps, for example, almost 150 million people cross the mountains every year, mostly by road. This heavy traffic contributes to emissions of nitrogen dioxide that turns into acid rain and damages forests and other ecosystems.
Roads, dams and other infrastructure can play important roles in the economic development of communities. The key to their environmental success lies in examining all options, evaluating their placement in the landscape. If the project can’t be avoided, finding a path that that is economically, socially and environmentally responsible is crucial.
Advocating for Sustainable Dams
Hydropower is a renewable resource, but dams can have a devastating effect on the environment. WWF actively engages with banks and hydropower companies to ensure broad-based improvement of practices. We encourage banks to adopt transparent lending guidelines to ensure that investment decisions are made responsibly. And we advise private and public sector institutions on how to improve the selection of projects and mitigate those impacts that cannot be avoided.
Influencing Better Road Design and Planning
Roads can provide vital economic links for isolated communities, but they can also contribute to environmental disasters. WWF works to influence road building at the design and planning phases so that the impacts of these projects, both direct and indirect, may be reduced. We do this by promoting the use of social and environmental criteria during planning and design and advocating for national and regional policies that incorporate sustainability concerns.
Protecting Sensitive Areas from Development
Some areas of the planet are simply too vulnerable to allow activities such as oil extraction or mining. WWF identifies sensitive areas and works with governments, industry and other leaders to protect them from development.