Jeff Opperman, senior freshwater scientist, has been working to protect rivers and lakes for nearly 15 years. Much of Jeff’s focus is on improving the environmental sustainability of hydropower both by advancing sound policies and by supporting on-the-ground projects.
Where Does Your Water Come From?
An important question that few people in the U.S. can answer. For most people, their city or town collects water from a lake or river. Of course, before reaching a specific water body, water first falls as rain or snow and then flows across land and through soil.
Water’s path from precipitation to our tap illustrates, simply and powerfully, the direct connection between nature’s health and our own: water that flows through a healthy watershed (the land that drains into a lake or river) is cleaner than water flowing through a degraded or polluted watershed. (Watch a video of my 8-year old son, Luca, demonstrating this concept).
So we can all make that connection pretty easily. But here’s the next question, and it’s equally important to both people and nature:
Where Does Your Water Go?
Much of the water delivered to homes is actually used outside the house and, in warm and/or dry parts of the country, lawns and landscaping soak up the large majority of all domestic water. Much of that water, along with the rain that falls on your house and lawn, ends up somewhere downstream.
If you care about your watershed—where your own water comes from—you should also realize that your lawn is part of someone else’s watershed. (If you live in a region like the Great Lakes, you are your own watershed—meaning the water that flows off your property ends up right back into your source of water.)
Even if the water flowing from your property doesn’t go back into your drinking water supply, it still ends up someplace that you or others care about: a local stream, river or lake and, eventually, the ocean. Thus, ensuring this water is as clean as it can be is one of the most important, and personal, contributions you can make to protect the environment.
For example, much of the fertilizer applied to lawns is carried away during rains (or excessive watering) and ends up in rivers, lakes or the ocean. There, the nutrients from the fertilizer continue to do their job of promoting rapid plant growth. In water bodies, that means pea-soupy blooms of algae.
Algae cells don’t live long and when they die in their billions they sink to the bottom, decompose and, in so doing, rob the water of oxygen, causing “dead zones” and fish kills.
While agriculture is the largest source of excess nutrients to water bodies, lawn runoff contributes to the overall problem and can be a major source at the local scale. What can you do? See below for five tips:
Five Ways to ‘Green’ Your Lawn and Garden Care
- Use Less Fertilizer
Excess fertilizer flows off your lawn and garden and ends up in nearby rivers, and lakes and eventually make its way to the sea. If you must use fertilizer, get a soil test first. Find out what your lawn needs. Use only what you need, and make sure it stays on the lawn. If you spill some on the sidewalk, sweep it up. Many lawns don’t need phosphorus, for example, so phosphorus-free fertilizers might just work for you. And only use it when the lawn is growing. Remember that any kind of fertilizer, organic or chemical, can be over-used.
- Slow Your Runoff
We all want to keep our properties from flooding, but when all the water washes off city streets and our rooftops and yards, it carries a lot of nutrients and sediment with it. These materials can be harmlessly processed by the soils and plants on your property, but in a lake or river they can cause real problems. To slow that water down, don’t cut your grass along a creek or drainage swale. Better yet, replace grass with native plants that will bind the soil and slow down the water. Or maybe create a water garden, which is both functional—it holds and slows down stormwater—and an attractive landscaping feature. Or buy a rain barrel for the water coming off your roof. The rain in the barrel can then be used to water your gardens and lower your water bill.
- Create Less Waste
Grass clippings are high in nutrients so you want to keep them out of the water. Use a compost bin or use a mulching mower or both. Often, mulching your grass clippings can help reduce the need for fertilizer. And it’s good to keep the nutrient-rich grass clippings and leaves out of storm drains and of ditches. Cutting your lawn high (3-4 inches) also increases its vigor, shades out unwanted weeds, and requires less water.
- Use Native Plants
In general, using more native plants that are right for your part of the world reduces the need for fertilizers, pesticides and watering. Replace some of your lawn with wildflower gardens, for example.
- Buy Sustainable
Although home lawn care can play a significant role in keeping fresh water clean, you can also help promote healthy land and water with your food choices: what you buy, when you buy it, and the producers you support with your purchases. You can make choices about food that support the kind of farmers who work to minimize water pollution. Organic farms, for example, don’t use chemical fertilizers and are required to demonstrate that they are protecting their watershed.
For more practical steps you can take to reduce the amount of excess nutrients you add to the watershed where you live, watch the video “Green Choices for Lawn and Garden.”
Read more about protecting fresh water resources at www.nature.org/freshwater.
(Image: Sprinkler watering a lawn. Image credit: Robert S. Donovan/flickr via a Creative Commons license.)