June is National Rivers Month! This is a good reason to explore and enjoy a river if you can. Rivers and their tributaries are the veins and arteries of any ecosystem, the “lifeblood” of communities near and far. Unfortunately, climate change is impacting rivers around the world in multiple ways, some of which are noticeable, and some of which are subtle. Both water quality and quantity suffer. Rivers aren’t the only things that are affected: climate change impacts the lakes, ponds and streams that connect to rivers, and the people, animals, and plants who live and work in those watersheds.
Climate change 101
Increased CO2 in the atmosphere is raising average global temperatures, which results hotter temperatures, warmer oceans, and melting glaciers. Paradoxically, climate change increases droughts and floods, both of which are bad for river ecosystems.
Here’s a short summary of how climate change impacts ecosystems:
- Warmer oceans may be changing weather patterns, leading to more powerful storms that pack greater wind speeds and dump more precipitation.
- Melting glaciers raise sea levels, yet that glacial melting doesn’t fill aquafers, it starves them. Many aquifers around the world depend on glacial snow and ice packs for a steady supply of groundwater that seeps from glaciers.
- Hotter temperatures not only make it more difficult for humans to live, but also make it hard for some species of plants and wildlife to thrive.
- Droughts make it more difficult for people to get drinking water, firefighters to fight fires, farmers to grow food, and wildlife and plants to survive.
Floods from intense storms
According to the US National Aeronautics and Space Administration. (NASA), there is no clear consensus that rising global temperatures affect weather by increasing the size, frequency and, possibly, duration of storms. Anecdotally, at least, it does seem that “100-year storms” are becoming a misnomer, because they have begun happening every few years instead of every 100 years. Such storms with above-normal precipitation can lead to flooding of waterways. Floods may not only damage buildings and roadways, but also wildlife habitats, through increased erosion and sedimentation, and pollution caused by the stormwater runoff from sewers, roadways, and farms.
Floods from sea-level rise
Various regions, including some here in Massachusetts, see the direct impact of sea level rise; Boston harbor is more frequently overflowing into nearby city streets compared to past decades, and waterfront homes from Cape Code to the north shore and south shore are increasingly flooded, damaged by waves, or washed out to sea. Since rivers always flow into a sea or harbor, a higher sea level can create problems such as an imbalance of salt water and fresh water in salt water estuaries.
Droughts
Unless you’re new to this planet (or have been living under a rock), it’s common knowledge that some rivers, such as the Colorado River in the western US, are shrinking, due to the combination of climate change and residential, commercial, and agricultural usage. If you lived in Massachusetts in 2022, you can probably recall that an intense drought made some tributaries and ponds shrink, or in some cases, dry up. Such droughts have negative impacts on wildlife of all types, from aquatic species such as cold-water trout that need deep, cool streams, to wetland plants, to mammals and birds that get their food from waterways and wetlands.
What are some nature-based solutions?
As individuals, we may not be able to control the climate change problem on a grand scale, but here are some things we can do at a local level to help rivers be resilient in the face of climate change:
- Reduce impervious (hard/paved) surfaces
Pavement and hard-packed turf increase the volume and speed of stormwater, so de-paving is one way to help water seep into the ground and filter out water-borne pollutants. This can be done on a large or small scale. One grassroots example is a group called DePaveHub in Somerville, MA, where volunteers help neighbors remove pavement from their yards to restore natural green spaces.
- Install riparian buffers
Riparian buffers are physical barriers that prevent development, encroachment, or disturbance along the edge of a stream, lake or wetland. They can be constructed with vegetation or engineered with man-made materials.
- Create greenways
Woods and meadows mitigate carbon emissions by acting as carbon sinks or reservoirs, and by taking in/sequestering CO2 during the process of photosynthesis. They also mitigate floods and droughts; forests and fields reduce flooding by soaking up excess water, and they retain water in times of drought. Here in north central Massachusetts, the Nashua River Watershed Association works closely with local greenway committees, landowners, communities, conservation groups, and public agencies to help them protect and improve riverfront greenspace.
- Conserve water
Water conservation measures help to sustain adequate water levels for everyone’s needs. Water restrictions typically vary by region or town. Here in Massachusetts, the Massachusetts River Alliance is advocating in favor of HD.1557/SD.142, “An Act relative to maintaining adequate water supplies through effective drought management,” sponsored by Senator James Eldridge and Representative Joan Meschino.
As you walk, drive, or bicycle by a river, observe what has been done, and what might be done, to protect that river and its tributaries. Do you know a good example of river protection you can share with the CounterAct Climate Change Project (C3)? If so, email me — joy (at) joyreo.com— a photo and I’ll share it on the C3 social media channels!
