Urban Planning for City Leaders - Cities Alliance

Urban planning for city leadersCoordinate urban planning andinvestmentTap on urban planningfor efficient infrastructureinvestmentThere are significant advantages inapproaching spatial and infrastructureplanning together. One advantage is that itenables investment to respond to urgent needswhile addressing long-lasting, cross-cuttingissues. Infrastructure investments trigger andenable urbanization, while spatial planningprovides proactive demand-side management.A city’s spatial structure determines the location,concentration, distribution and nature of thedemand that affects the design of infrastructuresystems. Because it establishes the physicaland economic parameters for infrastructuresystem design, capacity thresholds, technologychoices and the economic viability of thevarious options, spatial planning would benefitfrom early interaction with infrastructureprogramming. The available budget forimplementation will be used more efficiently,time would be saved and misalignmentsbetween supply forecasts and actual needswould be reduced.Spatial plans can improve infrastructurecost-efficiency. The cost of providing trunkinfrastructure is particularly sensitive to a city’sspatial form. 158 Lower densities generallymean longer lengths of water and sewer pipes.Reducing the distance to service centres, thusshortening the length of transmission mains,will lower costs. Spatial plans provide valuableinformation on prioritization of delivery. Theright decisions on density and land use policiescan induce earlier amortization as investmentwould be deployed where and when it isneeded. In various locations in the UnitedStates, infrastructure costs (annualized capitaland operating) were 30 per cent higher fordevelopment with 11 dwellings per hectarethan for 32 dwellings per hectare. 159 In theUnited Kingdom, a density of 70 dwellingsper hectare produced savings of 63 per centcompared with 22 dwellings per hectare. 160Spatial choices that can help optimizeinvestment• Optimize density by redeveloping ofvacant, derelict or underdevelopedsites; maximize the capacity of existinginfrastructure through management• Ensure that greenfield developmentoccurs in a compact pattern tominimize the amount of networkinfrastructure required; set densityat an optimum value; consider thelocation of central facilities whendetermining new development areas• Avoid discontinuous growth in areaslying outside the urban fabric, unlesssuch nodes can be self-sustaining,which would require a balancedsupply of jobs and housing.• Promote a closely mixed patternof land uses that minimizes roadinfrastructure requirementsInfrastructure networks influence spatialplans. Infrastructure can shape a city fordecades, if not forever, and decisions onwhere to lay it out influence the direction ofdevelopment affecting the desirability andland value of the areas served. Infrastructureplanning should follow and not precededecisions on the optimal spatial structure.142