Four Ideas for Greener Cities
For the first time in history, a majority of humans live in cities. How we make and use our cities has a major impact on how healthy the planet is, and how healthy and happy we are. I want to explore some options for creating greener cities, from the personal level to the city level. What are the most sustainable options for greening our cities?
Make greener yards
One step that may not be obvious is improving our own yards, where we must reduce the use of pesticides on lawns. According to the group Beyond Pesticides, “Suburban lawns and gardens receive more pesticide applications per acre (3.2-9.8 lbs) than agriculture (2.7 lbs per acre on average).” (http://www.beyondpesticides.org/lawn/factsheets/facts&figures.htm.) Many commonly used lawn chemicals have never been tested for their effects on humans, pets, and wildlife. We don’t know if they’re relatively safe or not—but they’re sold and we use them anyway. Of those that have been tested, some are linked with cancers of various kinds, birth defects, reproductive effects, liver and kidney effects, and endocrine system effects. Some are linked with increased risk of cancers in dogs, and are toxic to beneficial insects and birds.
That said, it’s reasonable to presume that all chemicals are potentially dangerous, even if used as directed. Therefore, minimizing the use of all chemicals is beneficial, and eliminating the use of as many chemicals as possible is preferable. I would distinguish between pests we should address for health reasons, such as mice and roaches and mosquitoes, and pests we simply dislike, such as crabgrass.
Eliminating the use of chemical pesticides, however, won’t remove the need for them. Fortunately, we have some options that are less toxic and nontoxic. Search for “nontoxic pest control” and you’ll get some ideas. The most crucial step, and possibly the most difficult, is managing your expectations. It may not be possible, for example, to have a thick, green, weed-free lawn without the dreaded “four-step program” of fertilizer and pesticide. So get over it—this fertilizer and pesticide combo is exactly what we need to eliminate! It’s time to accept that heavy use of chemicals comes at a high price, and that you can choose to use nontoxic methods.
Stop wasting water
Another option for greening our cities is changing how we use and manage water. According to NASA’s Ames Research Center, lawns are America’s largest irrigated crop (WorldChanging page 160). This is a colossal amount of water and offers great potential for improvement, as much of that water is wasted. At the same time, many areas of the country experience seasonal water shortages, partly due to lawn watering, and most of the continental U.S. is now abnormally dry to in extreme drought. To put it simply, many areas of the U.S. do not have adequate supplies of water due to drought and/or a growing population, yet people continue to waste water on their lawns. And even worse—it’s usually drinking water!
At the city level, city officials are making changes such as using permeable paving surfaces to allow water to drain back to the aquifers, requiring grading and contouring of developed land to allow draining into the soil and minimizing draining into storm sewers, encouraging conservation with tiered pricing, and restricting lawn watering.
At the personal level, we have quite a few options, as well. Stop watering your lawn; let it fend for itself on rainwater. Reduce the size of your lawn and landscape with drought-tolerant plants. Collect rainwater with rain barrels and use for your garden and landscape first, and for your lawn last. If you must have a lush green lawn, determine how much water your lawn needs for your climate conditions and be sure not to overwater. Plant appropriate species of turfgrass for your climate. Consider installing soil moisture sensors to help you regulate the amount of water you use, and if you have an irrigation system, keep it well maintained and leak free. In some areas, you could even divert graywater from the washing machine and use it for irrigation.
Let it go
A third suggestion for greening our cities is strategic laziness. Let’s plant millions of trees and shrubs, and then relax. Let’s stop demanding a manicured look and let nature decide what works and what doesn’t. A perfect example is the land along our highways. Why do highway departments mow so much grass? They waste a lot of fuel and man-hours doing so, and prevent trees from sprouting and growing naturally. Most of this land should be a maintenance-free native landscape. Sure, areas next to intersections should be maintained for visibility and safety, but I see no reason why cloverleafs must be mowed in their entirety. Some people will complain, as they want it all to look tidy like their lawns at home, but many of us prefer the natural look. It’s cheaper and healthier, anyway.
This idea of strategic laziness pertains to cities, as well. I noticed in Berlin, Germany, that the amount of urban vegetation was much higher than, for example, Minneapolis. I saw more weeds and grass growing in sidewalk cracks, and more “unmanicured” shrubs and trees on property boundaries. That translates into less gas-powered maintenance, and less herbicide use. In contrast, here in Wisconsin most homeowners keep their yards very tidy and have plenty of lawn area with too few shrubs and trees. They maintain their yards with gas-powered mowers and spray glyphosate to keep it all weed-free. They prune and shape shrubs into tidy round balls. Lots of room for improvement. This is anecdotal, of course, but would be interesting to study further.
When we talk more specifically about the urban forest, or our city trees, the benefits of a city filled with trees are well documented. Our urban forests are crucial to making our cities greener, as they:
- sequester carbon
- improve air quality
- moderate heat and save energy
- moderate high winds
- filter water and moderate erosion
- increase real estate values
- as well as providing benefits to people such as calming us and helping us slow down a bit.
Greening our urban waterways
Last for this post is our abused urban waterways. What’s left of them, anyway. So many have been filled in, paved over, straightened, turned into open sewers, and treated as dumps, but the potential for improvement is huge, and it’s crucial that we improve them. The U.S. Environmental Protection Agency has created the Urban Waters Movement to do that, by working with communities to reduce pollution entering rivers and to repair the damage. Many urban waterways are being restored to a more natural state and are once again accessible to people, with parks and trails and access for fishing and paddling.
As the world becomes more and more urban, we have unmatched opportunities to green our cities. These ideas are just four of many, but would have substantial benefits.