Pedestrian and cycling policies, and judging a traffic management strategy

Overview

Low-traffic neighbourhood or filtered permeability and why packages of measures work better than single measures.

What you need to know

Answer each one before you reveal it.

Questions from this subtopic

Each one with the model answer underneath.

1. 1

   What measures make cycling a realistic urban transport choice?

   Model answer

   Physically segregated cycle tracks on roads with heavy or fast traffic, since research consistently identifies fear of motor traffic as the principal deterrent and painted lanes do little to remove it. Quiet routes and filtered neighbourhoods on residential streets where traffic volumes are already low. Redesigned junctions, because most collisions and most of the fear occur there. A coherent network rather than disconnected sections, since a route is only as good as its worst point. Secure cycle parking at homes, especially flats and terraces without a yard, and at stations, schools, workplaces and shops. Public bike hire and electric bike schemes, which widen the range and the hills that can be managed. Cycle training for children and adults. Carriage of bicycles on trains and buses for longer journeys. And routine maintenance, sweeping and winter gritting of the network, without which it is unusable for part of the year.

2. 2

   What measures support walking in a city?

   Model answer

   Footways that are wide enough for two people to pass, level, well maintained and not obstructed by parked cars, bins and signage. Direct routes that follow the lines people actually want to walk, rather than long detours to a crossing point. Frequent, well-placed crossings with short waiting times and enough green time for slower walkers, and level surfaces at side roads so pedestrians have priority. Lower speed limits and traffic calming, which reduce both danger and the perception of it. Pedestrianised and traffic-restrained central streets. Lighting and natural surveillance from surrounding buildings, since perceived safety governs walking after dark. Seating and shelter at intervals, which is what makes walking possible for older people. Step-free access, dropped kerbs and tactile paving. Clear signing with distances or walking times. And school streets and safe routes to school, which have a large effect because the school run is a substantial part of peak traffic.

3. 3

   Why do active travel policies concentrate on short journeys?

   Model answer

   Because a large proportion of all urban journeys are only a few kilometres long, well within cycling range and many within walking range, and because those short trips are disproportionately damaging: cold engines emit most on short runs, they are concentrated at peak times and in residential streets, and they include the school run. Converting even a modest share of them removes traffic exactly where congestion and air quality are worst, at very low cost per journey compared with any new infrastructure. It also targets the trips where the car's advantage is smallest, since in a congested centre a bicycle is often faster door to door once parking is included.

4. 4

   Evaluate active travel policy as a traffic management strategy.

   Model answer

   Its strengths are that it is by far the cheapest measure per user; that it delivers health benefits through routine physical activity that are large enough to appear in cost-benefit appraisals as the dominant benefit; that it produces no emissions or noise and needs very little land; that it is affordable to almost everyone and so scores well on equity; and that it supports local shops, since people arriving on foot visit more often. Its weaknesses are that it is limited by distance, weather, topography and the need to carry loads or children, though electric assistance and cargo bicycles address part of this; that unless routes are continuous and feel safe they will not be used, so half-built networks fail and are then cited as evidence that the policy does not work; that reallocating road space and parking is politically contested and generates opposition from drivers and traders; that access to a bicycle and to secure storage is itself unequally distributed; and that shared-use paths without separation create conflict between cyclists and pedestrians, especially for people with visual impairments. It should therefore be judged as one component of a package rather than as a substitute for public transport investment.

5. 5

   What is a low-traffic neighbourhood or filtered permeability, and what does the evidence show?

   Model answer

   Filtered permeability means using bollards, planters or camera-enforced restrictions to prevent motor vehicles driving through a residential area from one main road to another, while leaving the same routes fully open to people walking and cycling, and leaving every property accessible by car from the boundary road. The aim is to remove through traffic and rat-running from residential streets so that they become quiet enough to walk, cycle and play in. Evaluations of such schemes generally report substantial falls in traffic on the internal streets, increases in walking and cycling, and smaller increases on the boundary roads, which in several studies diminished over the following year as some journeys were changed or given up, a process known as traffic evaporation. The genuine disputes concern the size and persistence of the boundary road increase, which affects residents of those roads who are often less affluent, emergency vehicle and delivery access, and the quality of consultation, since schemes introduced quickly and without agreement have frequently been removed. It is also the standard way of reconciling the safety argument for enclosed residential layouts with the sustainability argument for connected walking and cycling routes.

6. 6

   What criteria would you use to evaluate a city's traffic management strategy?

   Model answer

   Traffic volumes and journey times across the whole affected area, not only where the scheme was built. Mode share, that is the proportion of journeys made by car, public transport, cycling and walking, and how it has changed. Bus journey times and reliability. Concentrations of nitrogen dioxide and particulates at monitoring sites, and greenhouse gas emissions from transport. Road casualties, particularly among pedestrians and cyclists. Accessibility for people without a car, and for disabled, older and low-income residents. The vitality of the town centre, measured by footfall, vacancy rates and trade. Capital and running cost against benefits. The distribution of costs and benefits, since these frequently fall on different groups. Public acceptability, because a scheme that loses consent is withdrawn. And persistence, since effects measured in the first months often differ from those measured after two or three years.

Other ways to work this

The same content, four other ways.

What is inside Levo

Six ways to work the same material.