I'm on a one person mission to better define urban design effects under the RMA. So far I have:
- discussed effects ratings and their purpose under the RMA
- tried to develop an 'effects equation'
- asked: is urban design normative or positive?
Commonly, the basic rationale for a degree of public control over buildings and development relates to managing negative externalities. This is where MfE's helpful report on the Value of Urban Design starts. There are negative externalities of poor design. These affect the public realm, as well as adjacent sites.
Negative externalities occur when production and/or consumption of goods (such as buildings) impose external costs on third parties outside of the market for which no appropriate compensation is paid. This causes social costs to exceed private costs. But we have to be very careful how we define these externalities. Is the effect of an ugly building beside a nice building a negative externality? Or is it just part of urban life?
Rather than being a negative thing, is urban design just about good things (including positive externalities), and by implication things where there maybe a financial incentive for designers and developers to add good things into their designs, in which case there is no need for public intervention?
If urban design is all just human behaviour, then won't people vote with their feet, avoiding areas that are poorly designed and flocking to areas and places that are well designed, and from this process of selection, their money and buying power. As such, is there an incentive for developers and businesses to promote good design? By why so much bad design if there is so much value to be extracted by good design? Is it that people have a high tolerance of bad design?
The MfE report on urban design also mentioned inconsistent time preferences. Developers may have shorter time horizons (higher 'discount rates') than the community as a whole (e.g. short-term profit to developers versus long-term health benefits to society). This means that the market will tend to provide a level of urban design than is not socially optimal.
These points provide a helpful starting place. But somehow urban design is more complex than this. While concerns about poor quality design on a next door site driving down property values is a common basis for communities to call for urban design, to me the real issue relates to the importance urban design plays in supporting a functional public realm. The importance of the public realm to well functioning cities seems under recognised in most urban economic analysis. The public realm is not a tradeable good, it has a value but no price. It is not subject to the laws of demand and supply.
Many of the dis-benefits of poor design are less tangible social, environmental or well being impacts affecting a range of parties, over a long period of time. They tend to be second order effects (if there is such a term). Adverse effects of bad design are often incremental and cumulative, they are not necessarily all obvious 'blots on the landscape'.
If we take Jayne Jacobs and her prescriptions in The Death and Life of Great American Cities as a starting point, then we have the following four basic ingredients to generate (in her words) urban vitality:
1. The district must serve more than one primary use, and preferably more than two.
2. Most street blocks must be short.
3. Buildings must be mingled in their age, condition, and required economic yield.
4. A dense concentration of people.
I think it is reasonable to say that the third and fourth conditions are enabled conditions, in that there are characteristics that need to be allowed for and encouraged. The third condition does not mean heritage protection, although that may be a component. I think what Jacobs meant was that redevelopment should be an incremental, even scattered process, not a concentrated or cataclysmic process (as was much public urban regeneration schemes of the day). In contrast, short blocks and mixed uses are not necessarily elements that are always provided.
Jayne Jacobs did not stop with the four characteristics. She also (famously) referred to the need for ‘eyes on the street”. To her, vital, safe streets had the following elements:
"First, there must be a clear demarcation between what is public space and what is private space. Public and private spaces cannot ooze into each other as they do typically in suburban settings or in projects.
Second, there must be eyes upon the street, eyes belonging to those we might call the natural proprietors of the street. The buildings on a street equipped to handle strangers and to insure the safety of both residents and strangers, must be oriented to the street. They cannot turn their backs or blank sides on it and leave it blind.
And third, the sidewalk must have users on it fairly continuously, both to add to the number of effective eyes on the street and to induce the people in buildings along the street to watch the sidewalks in sufficient numbers. Nobody enjoys sitting on a stoop or looking out a window at an empty street. Almost nobody does such a thing. Large numbers of people entertain themselves, off and on, by watching street activity.”
So I think we can translate these ingredients into the following core urban design elements:
1. The nature and extent of the public realm network
2. The range of activities that border that network (the density and mix of uses)
3. The quality of the public private interface of that network.
If we look at these ingredients in turn, then a somewhat more complex rationale emerges as to the reason for intervention.
Public network
The nature and extent of the public realm network is important to functioning of urban areas. Cities need lots of routes and linkages. Short, interconnected street blocks help with walkability and access to public transport and local services. They promote health and well being through active transport. They generate street-based activity which helps with a sense of safety and 'connectedness' .
Jayne Jacob’s principle of short blocks is the common urban design principle of promoting connectivity and permeability. The UN-Habitat’s Global Urban Observatories Unit report on Streets as Public Spaces and Drivers of Urban Prosperity argues that streets should be counted as public space alongside leafy parks and landscaped plazas. Together, they should make up 45 to 50 percent of a city’s land area, with 30 to 35 percent of the area occupied by streets and 15 to 20 percent open space. “If less than 30 percent of the land of the city is dedicated to the street pattern, it’s a huge error,” Beside the economic value of streets on the land market, streets have an economic and social value related to productivity, infrastructure, quality of life and social inclusion.
The argument for intervention around the network is that as land increases in value, then there is a tendency for less of that land to be devoted to public space. In economic terms, this conception of the public realm could be thought of as an inferior good. A normal good is a good that is in greater demand as incomes rise. An inferior good sees the opposite outcome – demand shrinks as incomes rise. In a city, as incomes and land values rise, there is an incentive for development to provide less and less public space as this has a bigger and bigger cost. Furthermore, the value added by streets to the value of plots and buildings are not well factored in the land market. Neither real estate developers nor land owners are willing to appreciate the economic value of streets against its social value.
In this conception, the street should not be considered as an inferior good, rather the street should be considered as a normal economic good if not a superior good that should be allocated more share in the expansion of cities.
Mixed Uses
Diversity of activities along the main routes of the public network is crucial to urban outcomes. Here you might think that a removal of single use zonings would enable and allow for diversity of activities to flourish. There is no need to mount a case to intervene to support mixed uses and diversity of activities. But why are mixed uses so rare in cities, especially the bits built post war?
Jacobs noted that diversity tended to destroy itself, particularly as one use becomes dominant and bids up rents to the point where other uses flee. This results in a single-use office district, restaurant strip, etc. Density and diversity of activities can also be related to the diversity of the building stock. Mixed uses need a range of cheap and expensive premises that are big and small. Mixed uses also often take a while to get established. A catchment of people needs to be built up first, then the service-based activities start to flourish, but short term time horizons mean that developers may favour the residential phase.
One of Jacob’s cures for self destruction of diversity was to zone large areas for diversity. However this is not in the sense of requiring a set mix of activities. Rather it was first to zone for a diversity of building stock. This is in terms of building ages and building sizes. She cites the example of a park having lower buildings on one side to let in sun, but also to offer a choice compared to taller buildings on other sides. This in turn creates opportunities for different types of mixed uses. Elsewhere she mentions the importance of having many old buildings to provide cheaper space for new activities to get established. She acknowledged that maintaining a diversity of building stock would require some sort of financial acknowledgement. Hence perhaps why the idea never took hold. It also requires some form of gradual process of redevelopment of an area, not a ‘catastrophic’ replacement of buildings (and hence her call for a mix of old and new buildings).
The other cure was to have lots of opportunities for mixed uses to locate in a city. If one neighbourhood sees a loss of diversity, then provided the displaced activities had somewhere else to go to, then the city as a whole does not see a negative effect.
Whether the self destruction of diversity provides a rationale for intervention is difficult to say. One study (The Impact of Mixed Land Use on Firms An empirical investigation on commercial property transactions, Francis Ostermeijer July 2016) suggests that in a rational market, one would expect that firms involved in mixed land use patterns are likely to relocate until the marginal benefits and costs of relocation are equal. This implies a degree of natural mixing. "In reality however, this rationality assumption may not hold. It is perhaps more likely that there will be a sub optimal provision of mixed land uses. Therefore, land use regulation may be warranted in order to encourage a balanced mix of uses in order to maximise the net social benefits from mixed land uses".
For example, from a developer and landowner’s perspective, horizontal mixed land uses are preferable to vertical mixed land uses. This may be because the positive externalities from a diverse composition of land uses on a street such as pedestrian safety, higher aggregate demand and a better distribution of demand may not outweigh the costs imposed on individual activities in a mixed use building due to concerns over less privacy, increased security risks, less prestige and greater uncertainty of leasing of space when in a vertical mixed use situation.
Another way to look at the issue of under supply of mixed uses is that they are a merit good. A merit good is a good where consumption of the good generates an external benefit to others, from which society gains, but that benefit is unlikely to be known or recognised at the point of consumption. Given that decisions to consume are driven by self-interest, it is unlikely that this external benefit will be taken into account when the consumer of a merit good evaluates its worth. As a result merit goods are often relative to their wider benefit.
So maybe there is a rationale for seeking mixed uses. But is that rationale based on finding an incentive or some form of support for greater provision of mixed uses, rather than a sanction?
Quality of the public private interface
The public realm is more than just the network of public streets or areas of public open space. The public realm extends to the buildings, activities and private spaces that front onto these areas. The quality and functionality of public spaces is very dependent upon what fronts them; how buildings interact with public spaces. No amount of flash landscape design can lift a street or public space if it is surrounded by dull buildings. The public realm can also be described as the spaces within a site that the public can access without having to ask permission, such as laneways. But it is the areas owned by the public which are critical to the social and economic success of cities. Nice buildings fronting a street or open space does not automatically mean that the road or open space will deliver benefits. People using the space generate the value.
The public realm of a city is a ‘public good’. Public goods are goods that have the following characteristics:
• Non-rivalry: This means that when a good is consumed, it doesn’t reduce the amount available for others.
• Non-excludability: This occurs when it is not possible to provide a good without it being possible for others to enjoy.
You can quibble if a road or open space is non rivalrous. At some point, one more person added to a street or open space may make that place overcrowded or congested. Technically a road or open space is a quasi public good.
The problem with public goods (quasi or not) is that they have a free rider problem. This means that it is not possible to prevent anyone from enjoying the good, once it has been provided. Normally this creates a problem of payment and overuse: there is no incentive for people to pay for the good because they can consume it without paying for it. People can over consume public resources – the tragedy of the commons.
The public-private interface is a bit different. It is not about the over use of the public road or public space. Rather there can be a natural tendency for private development to ‘sponge off’ a high quality public realm, rather than contribute to that realm. For example, I will erect a larger fence across the front of my property to keep me safe and private, but I will still wander down the road in the evenings enjoying looking at the various front gardens and feeling safe because of the passive surveillance offered by all the housing which has windows to rooms that overlook the street.
Back to effects rating
Back to the question of an effects rating. What does the above tell me about urban design and effects? That it is not straight forward? That is hardly a revelation.
The above provides a framework by which effects could be organised or grouped, but does it help with determining the magnitude or persistence of the effect? Is my effects equation up to the task? Perhaps not.
What the above does suggest is that rather than be some sort of minor to major negative externality rating, any urban design rating framework needs to be more focused on the support or not for a well functioning public realm.
