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The Zoning Reform Tracker is meant to serve as a hub for documenting zoning reform efforts across the United States. In the first version of the Zoning Reform Tracker, we focus specifically on municipal zoning reform efforts, though we plan to expand this work to account for state reforms within successive updates. It is our belief that anti-density zoning ordinances play a powerful role not only in propagating race- and class-based exclusion, but in shaping life outcomes for children in communities, and therefore, in furthering patterns of negative intergenerational stratification. Restrictive zoning is a powerful mechanism for hoarding resources, with great implications for racial residential segregation, and the former will not fundamentally change without reforming or overriding zoning regulations at the municipal level.

There are two components to the Zoning Reform Tracker: the database, and the webmap. The database is a sortable list of municipalities which each have had some character of a zoning reform initiative, and inclusive therein are columns that describe various components of a given reform initiative. The database is then our most detailed collection or representation of zoning reform efforts across the United States. The webmap, on the other hand, is an interactive national map that marks the points of each reform initiative, and allows the user to explore the question of location, in terms of zoning reform initiatives occurring at the municipal level across the United States. The table below includes the full range of variables captured within the database, while the webmap displays a more focused set of information, which points the user towards the more extensive information contained in the Database. Comprehensively, we believe that this is an important tracker that can not only inform the public, but can also provide support for advocacy efforts across the United States.

The purpose of this page: “Zoning Typology - Reform Mechanism'' is to provide a Reform Mechanism Typology, a classification scheme that describes the policy mechanism through which a given zoning reform effort is carried out. This page provides the categories we use for the policy mechanisms of the zoning reforms efforts that are captured in our tracker; as well as the definition of our reform mechanism typology, its subclass specifications, and how we deploy them in our Zoning Reform Tracker. The Reform Mechanism Typology is meant to describe the how of a zoning reform effort, and/or the political typology of the policy mechanism carried out therein. The subclasses in the typology can be seen below:

Municipal Reform Mechanisms

  • Municipal Ordinance
  • General Plan Update
  • Intensive Zoning Code Effort
  • Ballot Measure

Justification for Reform Mechanism Typology 

This section is meant to provide a justification, or otherwise an explanation, of our particular reform mechanism subclasses. In this section, we justify our classification, and describe it fully so that viewers can understand it when interacting with the Zoning Reform Tracker. In the first version of the Zoning Reform Tracker, we focus specifically on municipal zoning reform efforts, which is another way of saying that we focus predominantly on city-based reforms; this focus is a consequence of cities primarily bearing control over land-use, zoning and planning decisions for the land within their jurisdiction. At the same time, and on the other hand, counties are another form of municipal reform governance, because they control land-use for unincorporated areas which are not formally located within the jurisdiction of any incorporated city.1 For the purposes of understanding the first publication of municipal zoning reform efforts in our database and webmap, the majority of reforms are carried out by a city council, with a smaller segment of reforms enacted by a board of supervisors, a board of alders, or a city commission. 

Concerning our definition of reforms, there is a dual-criteria that efforts must meet in order to become incorporated into our tracker: the first item is substantiality, and the second item is distinction. The former item of the criterion is fulfilled if an action institutes substantial change to land-use provisions or the exclusionary basis of single-family zoning, which will ultimately have effects at the municipal level. The latter item of our criterion is fulfilled if a given measure, bill, ordinance, or initiative is marked by either time-based distinction (wherein reforms efforts are separated by months or years), subject-based distinction (wherein reform efforts are distinguished by their reform mechanism or reform type), or by a combination of both.2  On a related note, we have also made separate definitions for reform efforts at both the municipal and state levels of governance, which guide our work. We define a municipal reform as a substantial change in the zoning code or a substantial change in what is known as the general/comprehensive plan of a municipality; with this specific change having implications for reducing the exclusionary basis which has been constitutive of single-family zoning, or general land-use provisions, historically. On the other hand, we define state reform as a substantial change in state policy which has implications for outcomes at the municipal level, and likewise, has specific implications for reducing the exclusionary basis of land-use and single-family zoning.3  

In turning towards our Reform Mechanism Typology, we will describe several items: the definition of our reform mechanism typology, its subclass specifications, and how we deploy them in our work. The reform mechanism typology described herein and used in our Zoning Reform Tracker is not transferable across municipal and state-based reform efforts. Whereas the municipal level of governance is privy to a varied set of mechanisms to enact zoning reforms, it seems that at the state level, there exists a more singular legislative route to enact reforms. In response to this, we define municipal reform mechanisms as a distinct typology in the first publication of this work, and then we will additionally include and specify the state reform mechanisms in a proceeding publication. In general, the municipal reform mechanism subclasses were constructed after researching the range of municipal reform efforts in the United States, and observing both the most preeminent examples, as well as, simply, the institutional constraints and capabilities that naturally marks municipal governance.

To continue, our Reform Mechanism Typology is a variable whose purpose is describing the means or method of a zoning reform effort; it is meant to describe the how, and/or the political typology of the policy mechanism carried out therein. In looking at this variable, the viewer should be able to answer the following set of questions: “How does this zoning reform seek to make its change? Through what method has it been enacted; will be enacted; or has failed to be enacted?” The typology itself has 4-categories which are reflective of the aforementioned set of questions on the means or method of a reform effort: 1) Municipal Ordinance, 2) General Plan Update, 3) Intensive Zoning Code Effort, and 4) Ballot Measure. Below we define and specify each subclass in greater detail:

I. Municipal Ordinance

Municipal governments primarily institute changes through drafting and passing ordinances. Ordinances are essentially bills which, when approved by a local legislative body and then successively by a given mayor, for example, become codified and incorporated into the legal statutes of the municipality.4 The legal statutes or laws for a given municipality often take the form of a municipal code. Therefore, in the cases of zoning reform, the codification of an ordinance of zoning reform would become incorporated into the municipal code, and specifically the segment of the code which pertains to zoning. An important feature to outline is the link between the municipal ordinance and what is called the general/comprehensive plan. The viewer should note that the tracker incorporates changes through both mechanisms and that either mechanism may constitute a reform effort, particularly when either are substantial changes and changes which have implications for reducing the exclusionary basis of single-family zoning. At the same time, while linked together in a political process, the two kinds of mechanisms are quite distinct. Zoning reforms are only codified through a municipal ordinance, and any reform that is made through a general/comprehensive plan update must become codified and instituted in the zoning code as an eventual step.5 An example of a municipal ordinance reform effort can be seen in Walla Walla (WA), which approved Ordinance No. 28-53, which was a Plex and ADU reform that allowed Plex development in what was prior single-family zoned land, as well as made the code more amenable to ADU development.6 Once passed, a municipal ordinance becomes written into the law, and becomes effective on its effective-date, which may or may not be near to the date when the ordinance was originally approved. A last note is that the timeline for an ordinance is usually rather quick, especially compared to general or comprehensive plan updates, and longer public-facing intensive zoning code rewrites.

II. General Plan Update

General plan updates are a significant kind of zoning reform mechanism, which have large implications for city planning, land-use provision, and the future-oriented design of the built environment.7 Indeed, general plans are the guiding policy documents which mark intentions, general strategies, proposals, and assertions, which then give the municipal governance the framework it uses to justify its incorporation of different reform ordinances and larger zoning code rewrite projects.8 As mentioned above, an important feature to outline intentionally is the link between general/comprehensive plan updates, and municipal ordinances. The viewer should note that the tracker incorporates changes through both mechanisms and that either mechanism may constitute a reform effort, particularly when either are substantial changes and changes which have implications for reducing the exclusionary basis of single-family zoning. At the same time, while linked together in a political process, the two kinds of mechanisms are quite distinct. Zoning reforms are only codified through a municipal ordinance, and any reform that is made through a general or comprehensive plan update must become codified and instituted in the zoning code as an eventual step.9

An example of a general plan update can be seen in Charlotte (SC), whose Charlotte Future 2040 Comprehensive Plan made an outline for Plex and ADU reform, which was eventually codified into the city’s zoning code just over a year later.10 In our tracker, we include general plan updates that are specifically intentional and direct about zoning reform; therefore, we typically don’t include a general plan update if its framing and recommendations don’t meet the two conditions we’ve established for incorporation into our tracker. Our inclusion is then related both to the framing of the general plan update process, determined by the language of the municipality, and that which is exported to the public by the media, as well as what the update actually entails. A last note is that the timeline for general plan updates is usually quite elongated; it may take three or more years for a municipality to adopt a new comprehensive or general plan, starting from the origin of the update process. This process itself is quite long because the documents drafted are voluminous, and involve a range of public input, as well as multiple series of review and feedback from the jurisdictions’ constituency.11

III. Intensive Zoning Code Effort

Intensive zoning code efforts are otherwise what would be called zoning code rewrites. These are longer term and public-facing projects which seek to get the public’s input in regards to forthcoming zoning code changes. These projects by nature are quite extensive and they often contain many different kinds of zoning reforms internally. A zoning code rewrite is different from a general plan update, in that it directly codifies changes into the zoning code – whereas the general plan update, in the case of zoning, is an outline of not-yet codified planning and land-use directives and recommendations.12 It is often the case that following an ambitious and reform-focused general plan update, a municipality institutes a broad and multifaceted intensive zoning code rewriting effort. Furthermore, the relationship with the zoning code rewrite mechanism must be specified from what we have named simply as the municipal ordinance mechanism. While both are codified through the same means: a municipal ordinance, the municipal ordinance mechanism usually represents a one-off or focused amendment to a specific portion of the code, or a specific type of reform within the code; on the other hand, the intensive zoning code rewrite mechanism represents an extensive long-term, and public-facing process, which usually enacts changes in more than one distinct domain of the zoning code.

We might view two reform efforts as a kind of comparison: the municipal ordinance of Philadelphia (PA),13 and the intensive zoning code effort of Somerville (MA).14 While the first reform effort, Bill No. 190612, was a focused ADU reform with the effect of permitting by-right accessory dwelling units (ADUs) in all single-family zoned lots across the city; the second, Ordinance No. 2019-25, was a more extensive and hefty ordinance. The Somerville zoning code rewrite amended many elements of the zoning code and included a broad form-based code provision that extended through the entirety of the jurisdiction, as well as an amendment which permitted ADUs on most residential land throughout the city, and finally, a provision which increased the affordability requirements for new developments substantially. We can see that the municipal ordinance mechanism is distinct and more focused as a method of change, in comparison to the public-facing and intensive process of the broader zoning code rewrite. A last note is that the timeline for intensive zoning code efforts is usually quite elongated, which make them similar to the general plan updates that usually establish their precedent and foundation; it may take two or more years for a municipality to codify its zoning code rewrite, because of the scope of the effort, and the iterative process between documentation and, often times, numerous rounds of public input.15

IV. Ballot Measure

Ballot measures are on the whole less prevalent than other mechanisms of zoning reform efforts across the United States, but while they are less representative, they are still an important potential strategy of reform. Though in theory, measures may be placed on a given municipal ballot by a governing body in order to grant the jurisdiction's voters decision-making power over the codification of a zoning reform,16 this has not occurred much, or at all, in practice. This may be caused by municipalities naturally having other institutional mechanisms for reform which they have utilized historically, such as focused ordinances, larger zoning code rewrites and general plan updates. In light of this, the ballot initiative mechanism we represent in our tracker is rather constitutive of those initiatives that are related to public and community organizing. It may be that the ballot initiative reform mechanism is a particular strategy of organizing that has a foundation in the coalitional housing politics of Los Angeles (CA). We might see this reform mechanism in practice in Measure JJJ, which was a transit-oriented development (TOD) reform put on the ballot by the Alliance for Community Transit-Los Angeles coalition (or ACT-LA), and passed by a popular vote in the City of Los Angeles.17 Only time will tell if this particular reform mechanism is burgeoning, or if it's merely an exceptional practice.

In closing, the aforementioned sections detail the Reform Mechanism Typology which we have used to classify the method or mechanism of reform efforts recorded in our tracker. In tandem with this documentation, the viewer can look towards our Reform Phase Typology which we have used to track the timeline characteristic of zoning reform efforts across the United States. Similarly, the viewer might also look towards our Reform Type Typology which we have used to track the different types characteristic of zoning reform efforts. Lastly, we have created a Database Metadata document, which shows information for all of the variables included in our tracker.

If there are any questions associated with this work, or if you believe that we have missed significant or crucial reform efforts, then let us know through this Google Form, and we may add them to our database and webmap. Other inquiries can be directed to cantong@berkeley.edu.

  • 1 See the language used in LAO, “A.G. File No. 2021-016” (California Legislative Analyst’s Office, October 15, 2021), https://lao.ca.gov/BallotAnalysis/Initiative/2021-016; specifically one part of the “Background” section, which reads: “Cities are responsible for local needs, such as planning, to accommodate needed housing, police and fire protection, and local roads. Counties provide similar services in areas outside of cities—unincorporated areas.”
  • 2 We must make a further point about the distinction criterion, particularly as it answers problems and questions related to the granularity of reform efforts included in our tracker. The problem might be framed as such: If a given municipality institutes multiple ordinances for the same type of zoning reform, within days of each other, then wouldn’t representing each granular municipal ordinance as a distinct reform effort serve to oversaturate the tracker for a particular jurisdiction? We address this problem with the distinction criterion. In short form: we include efforts into our tracker not only on the grounds of substantiality, but also on the grounds of distinction. We would then not specify two ordinances which were passed on the same day and over the same type of zoning reform, as two distinct reform initiatives; but we would and do include reforms for a given reform-type which are spread out by months or years, and define these as distinct reform efforts for the purposes of our tracker. It is sometimes the case that a given “reform” is enacted in two municipal ordinances, with one ordinance making most of the change, and the other ordinance instituting a more marginal change. Let us take Gainesville, FL for example. The City of Gainesville made an effort to remove single-family zoning in 2021, and it did so by passing two ordinances on the same day: Ordinance No. 211358, and Ordinance No. 211359. The first replaced single-family zoning with a Neighborhood Residential (NR) zoning category, and specified that up-to plex development would be permitted in this new district; the latter ordinance merely made marginal administrative and language changes to the Land Development Code. As these ordinances were approved on the same day, and were related to the same reform type, we believe that including them both in our tracker (both as rows in our database or as two distinct points on our webmap) would be over-representing Gainesville, which may have the effect of misleading the user, particularly if this same granularity wasn’t pursued in a uniform way across all other jurisdictions in the United States. This kind of oversaturation and granular irregularity would also have the prospective effect of adding error to future computational analyses done with our tracker data. In light of this, we specify the dual-criteria above. At the same time, the distinction criterion does not necessarily mean that we don’t track multiple rounds of reform efforts for a single policy which occur in a given municipality, or likewise, that we don’t track multiple types of reforms which are adopted within a short time-frame in a single municipality. To support this case, we direct the user towards our inclusion of Maplewood, NJ (two ADU reforms separated by a year), and Minneapolis, MN (a Plex reform and Other reform separated by a month). For information on Ordinance No. 211359, which we mentioned above and have not included in our tracker, see City of Gainesville, “File # : 211359” (n.d.), https://gainesville.legistar.com/Legislation Detail.aspx?ID=5711153&GUID=836A2CBB-72EA-4D78-B111-848C15847999&Options=&Search=
  • 3 These definitions are in dialogue with our previous work on single-family zoning in California, the outline on zoning reform established by Karina French in “Decoding Zoning,” and lastly, with our experience researching municipal and state zoning reform efforts across the United States. See Karina French, “Decoding Zoning: Regulation and Reform in California” (Berkeley, CA: Othering & Belonging Institute, May 13, 2021), https://belonging.berkeley.edu/decoding-zoning.
  • 4 See Gray Davis, et al., “A Citizen’s Guide to Planning” (Governor’s Office of Planning and Research, State of California, January 2021), https://www.acgov.org/sustain/documents/CitizensGuidetoLandUsePlanninginCalifornia .pdf
  • 5 Karina French, “Decoding Zoning: Regulation and Reform in California” (Berkeley, CA: Othering & Belonging Institute, May 13, 2021), https://belonging.berkeley.edu/decoding-zoning
  • 6 When citing a zoning reform initiative we usually, but not always, cite two different kinds of documents: the first are accessible media publications, and the second are bills, ordinances or the zoning code itself. In this way, the viewer can be directed to an accessible information source about the particular zoning reform effort, and then they can also have access to the ‘primary document’ which is the more objective reference base of our tracker. In this light, concerning the particular ADU example of Walla Walla (WA) above, the user may be directed to: Patrick Sissin, “Zoning Reform Creates New Model for Smart Growth in Walla Walla, Washington” (American Planning Association, September 21, 2022), https://www.planning.org/planning/2022/summer/zoning-reform-creates-new -model-for-smart-growth-in-walla-walla-washington/; as well as Walla Walla, WASH., Ordinance No. 2018-53, (2018). https://records.wallawallawa.gov:8643/lfportal/DocView.aspx?dbid=0&id=1153870&page=1&cr=1
  • 7 See Sahar Shirazi, Elizabeth Baca, Michael McCormick, Seth Litchney, et al., “State of California General Plan Guidelines 2017” (Governor’s Office of Planning Research, July 31, 2017), https://opr.ca.gov/docs/OPR_ COMPLETE_7.31.17.pdf; particularly the following excerpt: “The general plan is more than the legal underpinning for land use decisions; it is a vision about how a community will grow, reflecting community priorities and values while shaping the future” (p.1), as well as: “California state law requires each city and county to adopt a general plan ‘for the physical development of the county or city, and any land outside its boundaries which in the planning agency’s judgment bears relation to its planning’ (Gov. Code § 65300). The general plan expresses the community’s development goals and embodies public policy relative to the distribution of future land uses, both public and private” (p.10). It is worth noting that other jurisdictions across the United States do not have the same standards as California, and some municipalities lack either general plans or a zoning code entirely.
  • 8 Ibid. See the following excerpt from “Chapter 9: Implementation”: “A general plan is ineffective if not well implemented. Implementation relies on specific plans, zoning ordinances, subdivision ordinances, and public project consistency requirements, among other mechanisms… Zoning is one of the primary means of implementing a general plan. In contrast to the long-term outlook of the general plan, zoning classifies the specific, immediate uses of land… [it] must be consistent with the general plan” (our emphasis) (p.234).
  • 9 Gov. Code § 65860(c) (amended 1965). https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?law Code=GOV§ionNum=65860
  • 10 City of Charlotte, “Plan Policy” (Charlotte, SC: Charlotte Future 2040, n.d.), https://www.cltfuture2040plan.com/content/goal-2-neighborhood-diversity-and-inclusion
  • 11 For an example of the typical process of general plan updates, and the iterative rounds of drafting and public input which characterize it, we can look at the language of Escondido (CA) when describing the extent of public involvement in their update process: “Citizen participation will be relied upon to garner input on public opinions, visioning, recommendations and perceptions. A draft General Plan will be crafted along with alternatives that will be studied and analyzed. The City will make strategic use of consultants to complete certain technical studies required for analyzing the plan. Public input will be sought throughout the process during workshops, Planning Commission and City Council public hearings.” See City of Escondido, “Escondido General Plan Update Frequently Asked Questions” (n.d.), https://www.escondido.org/Data/Sites/1/media/pdfs/Planning/GPUpdate/FAQ.pdf
  • 12 See Sahar Shirazi, et al., “State of California General Plan Guidelines 2017” which reads: “The zoning scheme, with its range of zoning districts and their associated development standards or regulations, must be broad enough to implement the general plan. For example, if a general plan contains three residential land use designations, each with its own residential intensity and density standard, then the zoning ordinance should typically have at least as many zoning districts with appropriate standards… When rezoning occurs, the newly adopted zoning must be appropriate and consistent with all elements of the general plan” (p.257). Consistency is read here then as the zoning code rewrite executing and codifying the general plan, and putting it into practice, in a manner established by its foundational text.
  • 13 Jake Blumgart, “Philadelphia moves toward legalizing granny flats in historic buildings” (WHYY, August 23, 2019), https://whyy.org/articles/philadelphia-moves-toward-legalizing-backyard-cottages-on-historic-properties/
  • 14 City of Somerville, “Somerville City Council, Administration Pass City's First Zoning Overhaul in 30 Years” (December 13, 2019), https://www.somervillema.gov/news/somerville-city-council-administration-pass-citys-first -zoning-overhaul-30-years
  • 15 We can see an ongoing zoning code rewrite process in the City of Boise (ID), as an estimation for the time frame and the scope of this usual process for municipalities. It is often that the zoning code rewrite process may last between 2-4 years. Lastly, a zoning code rewrite, and the fact that a municipality may be undergoing one, does not necessarily signify that they are engaging in a zoning reform. It is possible and quite often that general plan updates or zoning code rewrites do not change much or register in regards to particularly our criteria of substantiality, which is fulfilled if a given policy lever implements changes in the zoning code which has implications for land-use provisions and changing the exclusionary basis of single-family zoning. For the reference to Boise, see City of Boise, “Zoning Code Rewrite - FAQs” (n.d.), https://www.cityofboise.org/departments/planning- and-development-services/planning-and-zoning/zoning-code-rewrite/zoning-code-rewrite-faqs/
  • 16 California Secretary of State, “Ballot Measure” (n.d.), https://www.sos.ca.gov/elections/ballot-measures; this page specifies that there are two means of placing a measure on the ballot, particularly in California: the first is by the legislature, but this is mainly for taxes, bonds, and constitutional amendments; the next is a by a local civilian referendum. Though this is California’s framework for ballot measures, this same referendum or initiative process seems to be common across other jurisdictions.
  • 17 See Bureau of Contract Administration, “Measure JJJ” (City of Los Angeles Department of Public Works, n.d.), https://bca.lacity.org/measure-JJJ