In his original plan for the city of Philadelphia, William Penn declared that every home should have ample space “for gardens or orchards or fields, that it may be a green country that will never be burnt and always be wholesome.” Before militiamen or throngs of protestors, the Boston Common nourished grazing cattle. Urban agriculture has cropped up again and again in cities throughout American history – from “relief gardens” for the poor in the 19th century, to “victory gardens” of World War II – and for good reason. If embraced and encouraged, urban agriculture can create economic, cultural, environmental and educational benefits. In recent years, various cities have developed good urban agriculture programs. By distilling their successes and struggles, my colleagues and I identify a series of best practices in this area.

Tailoring Programs for Varied Communities

“Urban agriculture” is an umbrella term encompassing a wide array of practices. Good programs take account from the start of community preferences that vary. Beekeeping or backyard chickens, for example, might be considered progress in Portland but backwardness in Baltimore. Controversies often arise, but they offer opportunities for dialogue. When disputes erupted about the 140-acre Hantz Farms proposal in Detroit, for example, officials convened public meetings to fashion a vision of urban agriculture. Cities like Portland and Vancouver have formed urban agriculture task forces composed of private citizens, government representatives, and organizational partners to advise the cities on planning and code issues.

In most cities, urban agriculture of some form is already practiced, whether regulations officially enable it or not. It is important to take stock of these existing operations and practices. Important elements to consider include: the number of gardens and gardeners, their demographics, the type and location of existing gardens, popular agricultural practices, and where space exists to expand urban agriculture. Numerous cities have benefited from conducting “urban agriculture land inventories,” in which mapping professionals use satellite imagery and public records to determine which publicly-owned plots are best suited to urban agriculture.

Communities should develop an independent agency or department to manage urban agriculture. Because urban agriculture is a multi-faceted process, many city agencies currently regulate its disparate aspects; Parks, Public Works, Environmental Protection, Sustainability, Health and Sanitation, Land Banks, and other departments all have their hand in working with growers. Centralizing this authority under one department can streamline regulation and simplify the process of establishing gardens and farms. Boston’s Grassroot program, Chicago’s Neighborspace program, and New York’s Green Thumb program are all excellent examples.

Municipalities should audit existing codes and laws. Although most relevant regulations will be found in local zoning ordinances, other codes might have unexpected effects on urban agriculture – including ordinances regulating produce sales, market stands, shade trees, and noise. In Los Angeles, a near-forgotten, yet narrowly-worded, 1946 “Truck Gardening Ordinance” threatened to limit agricultural sales exclusively to vegetables before it was amended by the city’s governing body. Municipalities should also be aware of state and federal regulations that might affect agriculture policy decisions. Right to Farm laws typically operate at the state level and may restrict localities. Notably, Detroit and other large cities in Michigan had to postpone regulation of urban agriculture until they were exempted from their state’s Right to Farm rules.

Ways to Facilitate Urban Agriculture

Although public sentiment should determine where urban agriculture is appropriate, there are opportunities to incorporate some form of agriculture or gardening in every land use zone. Cities from Seattle to Philadelphia have incorporated urban agriculture into existing land use codes. Small acreage projects unlikely to create nuisances include backyard gardens typical of single family homes and should be permitted virtually anywhere. Yet large acre, high nuisance projects – such as multi-acre urban farms relying on heavy machinery or animal husbandry – are better suited for the city edges or industrial zones.

While permitting urban agriculture outright in this fashion has proven successful, other creative ways that cities have enabled urban agriculture include:

• Creating new zones for urban agriculture specifically, as in Boston and Cleveland.
• Permitting urban agriculture as “conditional” or “accessory” rather than primary use. This allows local planning and zoning boards to maintain control over how such uses are developed, without restricting them. However, this approach can become too cumbersome and likely to disproportionately burden applicants with fewer resources.

• Land can be directly supplied — through adopt-a-lot programs and leasing underused spaces to citizens or qualified urban farmers. Offering flexible, medium- to long-term leases is critical, as security of land is vital to the success of urban farms.

Good Management to Sustain Citizen Projects

Finally, municipalities must take steps to ensure that citizens practicing urban agriculture do so responsibly. Some of the most effective approaches include:

• Passing or revising codes that limit the use of pesticides and fertilizers
• Enforcing time restrictions on the use of noisy farm equipment (although this is not typically an issue on small plots where hand tools are most common)
• Providing training opportunities through city departments or local cooperative extension services
• Requiring preliminary testing of land and monitoring of soil toxicity, soil nutrition, and any utility lines running through a property
• Offering  access to rain barrels or municipal water hookups
• Including urban agriculture in all future urban planning efforts, including master plans.

The Trump administration had been working hard to roll back the nation’s environmental regulations on the grounds that they are an economic burden on business. But evidence from California tells a very different story. For the past half century, California has been the richest U.S. state – even as it has led the United States in coastal protection, restricting oil drilling, regulating automotive emissions, promoting energy efficiency and, most recently, curbing greenhouse gas emissions.

From 2013 to 2016, California grew more rapidly than any other state – to become the world’s sixth largest economy. Not only have rapid economic growth and stringent environmental regulations proved compatible, many of California’s environmental regulations have promoted economic growth and benefitted businesses.

A History of Innovative Environmental Policy

California was the first government in the United States to impose pollution controls on motor vehicles. The campaign to do so was strongly supported by the Los Angeles business community, most notably its powerful real estate developers. They feared that unless the city’s air quality measurably improved, it would become more difficult for the city to attract new residents and businesses.

Thanks to the steady strengthening of both state and federal automotive emissions controls, air quality in Los Angeles dramatically improved. During the 1970s Los Angeles averaged 125 Stage I smog alerts per year, but it has not had a single one since 1999. In 2015, the city recorded its lowest smog level since reporting began. It is hard to imagine that Los Angeles would have continued to grow so substantially or become the center of the world’s entertainment industry as well as the location of so many high income communities had its air remained so hazardous.

California’s pollution controls grew out of a long history of collaboration between policymakers and business firms. In fact, California’s businesspeople and policymakers have been working together since the 19th century. To promote tourism in the Golden State, steamship companies wanted to safeguard Yosemite and the Southern Pacific Railroad became advocate of protecting the sequoias of the Sierra.

Most recently, California businesses have backed the state’s wide-ranging initiatives to reduce greenhouse gas emissions. California’s historic 2006 Global Warming Solutions Act mandated a reduction in greenhouse gas emissions to 1990 levels by 2020. It was backed by more than 200 individual firms and business associations, including the state’s high-technology and venture capital firms in Silicon Valley. By 2006, nearly $2 billion in venture capital had been invested in clean technology. As one state policymaker noted, “The legislation . . . sends a signal to people that there is a market where people can invest. . . So what started as an environmental issue in 2001 or 2002 has garnered a lot of business support.”

Economic Benefits of Smart Environmental Policies

Promoters of economic growth in California rightly see that regulations have opened doors for innovative businesses and reduced costs for citizens and enterprises alike:

• Thanks to the state’s promotion of renewable energy, 1,700 solar companies are based on California. The state accounts for half of the rooftop solar installations in the United States and a quarter of the nation’s solar energy jobs. Renewable energy mandates have been strongly supported by the state’s unions because of the jobs they create. All told, more than 500,000 people are employed in the state’s growing renewable energy sector.

• The state’s Advanced Clean Cars Program and its zero-emission mandates have led Californians to buy or lease more than 200,000 pure electric vehicles. This represents roughly half of all such vehicles registered in the United States, and has made California, along with China, the world’s largest market for this new automotive technology. Thanks to Tesla, California has become the center of electric vehicle technology, with several other auto manufactures opening design facilities in the state.

• Between 1974 and 2014, energy consumption per person in the United States increased by nearly 75 percent, while California’s per person energy consumption has remained nearly constant. The state’s energy-savings program, building codes, and appliance efficiency standards have reduced the energy bills of Californians by nearly $90 billion and have also saved the expense of constructing what could have been up to 50 new power plants.

In 2010, two Texas-based oil companies launched a California ballot initiative to roll back the state’s climate change commitments. Tellingly, this effort met with strong business opposition, especially from California’s clean technology sector, which by then had investments worth $6.6 billion. According to the Silicon Valley Leadership Group – whose participants reap worldwide revenues of more than $2 trillion – “our members believe that reducing greenhouse gas emissions and our dependence on fossil fuels presents an opportunity to transform the economy from one based on coal, oil, and gas to one that runs on clean renewable energy.”

California as a Model

The experience of America’s most populated and currently rapidly growing state challenges the claim that environmental protection hurts the economy. Often jointly backed by businesses and citizens groups, California’s environmental policy leadership has nourished prosperity, truly laying the foundations for the making of a “Golden State.”

As Washington now tries to retreat in environmental policymaking, more states can learn from what California has accomplished. Policymakers, advocates, and others concerned about economic growth and competitiveness should work to strengthen regulations and create new opportunities for firms that stand to benefit from a “greener” growth trajectory. When a state protects its scenic beauty, improves its air quality, reduces its energy use, and promotes renewable energy, it not only protects its environment, but also becomes a more inviting place to live, work, visit, and invest.

The rates of death and health burdens associated with air pollution are borne unequally and inequitably by people of color and those with lower household income and educational attainment in Washington, D.C., according to a new study.

Air pollution is considered the leading environmental risk factor to health, and recent efforts have successfully brought down levels of fine particulate matter, or PM2.5, in the air in the D.C. region.

The new study found that while deaths and health burdens associated with PM2.5 halved between 2000 and 2018 in the D.C. area, disparities and geographical segregations in health effects persist.

Most impacted by PM2.5 air pollution are people living in wards five, seven and eight in the District’s east and southeast regions. Researchers found in southeast wards, baseline disease rates are five times higher for chronic obstructive pulmonary disease, lung cancer and stroke, up to nine times higher for all-cause mortality and coronary heart disease, and over 30 times higher for asthma emergency department visits, compared to northwest neighborhoods.

In these most impacted neighborhoods, residents have 10% lower education and employment rates, 10% more residents are living in poverty, their median household income is $61,000 lower than households in the rest of the city, and residents have about 10 fewer years of life expectancy. The top 10 impacted neighborhoods have a 54% higher proportion of Black residents and a 44% lower proportion of white residents.

This study highlights the importance of detailed health and air quality data, and the researchers hope it can guide future policymaking to address environmental health disparities and serve as a model for addressing air pollution health assessments elsewhere. The research was published in GeoHealth, AGU’s journal investigating the intersection of human and planetary health for a sustainable future.

“We knew that concentrations were higher in the east [of D.C.], and we knew that people were getting sicker in the east, but I don’t know if we were able to tell before that they were getting sicker because of pollution,” said lead study-author Maria Castillo, a graduate student in City Planning at MIT. “Now that we apply all these calculations, all these concentration response functions, we’re able to tell people, ‘Air pollution is the cause of some of the morbidity outcomes that you are seeing in this area.’ Making that connection between pollution and health impact outcomes I think is very powerful.”

Unequal health outcomes can be attributed to two main drivers, according to study co-author Susan Anenberg, an environmental health expert at George Washington University. First, air pollution concentration differs by neighborhood. Infrastructure such as highways or bus depots can release significant pollution into a neighborhood, negatively affecting residents.

The second driver is an individual’s health status, independent of air pollution. Rates of underlying disease persistently differ by neighborhoods, with lower life expectancy and greater rates of asthma, health endpoints and emergency visits seen in D.C.’s southeastern neighborhoods. Those underlying health issues can make residents more vulnerable when exposed to pollutants and result in higher levels of poor air pollutant-related health outcomes.

“You can’t think about air pollution in isolation. When it comes to health risks and environmental justice, we have to think of the total lived experiences that people are having,” Anenberg said. “If folks don’t have adequate access to quality healthcare, that means when they are exposed and have health effects as a result of that air pollution exposure, they may have worse outcomes because they’re not getting the treatment that they need.”

Focusing on Fine-Resolution Data

Researchers worked with new exposure assessment tools to measure the impacts of air pollution in the nation’s capital. To evaluate air pollution, Castillo and her co-authors used pollution estimates that combined information from on-the-ground air monitors with satellite data to capture some of the spatial differences in pollution levels across the city.

For health outcome data, they looked at both Centers for Disease Control data as well as administrative disease rate data obtained from the D.C. Department of Health, which provided health data in greater detail on a local scale.

Researchers aim to take advantage of the unique position of D.C. as a city with thought leaders in environmental justice and policy, and with more granular health data than other states, to make scalable solutions applicable in other regions. They hope this study can be used as a model to not just bring down overall air pollution but create targeted policy.

“I think one of the strengths of the study is that it really laid out a road map that could be done other places,” said Jonathan Levy, an expert in Environmental Health at Boston University who was not involved in the study. “The air quality data they used, that’s universally available every place across the U.S. … there are real opportunities to take this kind of approach and do it much more widely.”

This study could also be used as a model help ensure policymaking is driven by health data that accurately reflects racial diversity and health outcome disparity in populations — something that was not historically the case, according to Kelly Crawford, study co-author and Associate Director of the D.C. Department of Energy and Environment.

“Doing further studies that at the very least acknowledge the disparity or lack of diversity in data sets… I think that is the role of government and research in addressing racism,” Crawford said.