Given most of the interchange areas are of agricultural and natural land use, uncontrolled growth can be detrimental to livelihoods, food security and biodiversity | File photo

“Prime block of land for sale in close proximity to the expressway interchange” is an increasingly visible advertisement that is sure to excite potential buyers. This same advertisement should, however, send shivers down the spine of attentive policy-makers and administrators, as it indicates a rapid growth occurring around the expressway interchanges. Smooth functioning of the interchanges is pivotal to the development of an effective and efficient expressway network given the role interchanges play in connecting main expressways to intersecting roadways. ***Development around interchanges can be a double-edged sword where controlled growth brings dividends, while uncontrolled growth creates headaches for motorists, land owners and local officials. ***
Uncontrolled growth around expressway interchanges can cause several major problems.

• A severe reduction in traffic-carrying capacity of the interchange is perhaps the most worrying of all. This would result in traffic congestion that prevents the interchange from functioning optimally. Furthermore, congested roads limit the access to adjacent properties, thus reducing the potential of such properties to reach the desired level of development.

• Strip development along the intersecting roads is highly likely in an uncontrolled scenario causing the parcels behind the strip development to become land-locked, thus losing their development potential. Strip development also increases the cost of installing utilities.

• Incompatible grouping of land uses is another problem. For example, scattered residential areas make it difficult to assemble suitably large sites for commercial and industrial development.

• It puts pressure on already inadequate infrastructure services as population grows in traditionally low-density rural areas.

• Given most of the interchange areas are of agricultural and natural land use, uncontrolled growth can be detrimental to livelihoods, food security and biodiversity.

• Needless to mention the fact that an unrestricted plethora of signs, billboards and utility lines make the interchange area unattractive, and in some cases confusing for motorists. Interchange development should fit into the surrounding landscape.

While it is not necessary to completely prevent this growth from occurring, it has to be carefully regulated if we are to minimise aforementioned negative impacts. In fact, interchange areas can be converted into development zones that fuel the local and national economy by putting a comprehensive spatial plan in place. It is worth noting that ‘one size fits all’ is never a viable approach to formulating spatial plans for interchange areas. Spatial plans should be sensitive to local economic, social, transport and environmental conditions. Following are some examples for controlled development in interchange areas that take into account local conditions.

• Rural Interchange Development: In rural locations, typically the land is used for agriculture or in a natural condition. For rural interchange areas, converting some land, in a way that causes the least possible damage to the environment, for highway-dependent business would bring the most benefits. Such businesses may include gas stations, restaurants and cafes or ones that serve local rural interests such as agricultural supply stores.

• Mixed-use Interchange Development: This is a type of development appropriate for areas with high population density. Under this development scenario, the area around the interchange provides a mix of land uses and services including residential, retail, and commercial businesses. It is important to get the location and the site layout right relative to the interchange to minimize the impact on interchange’s functionality.

• Business/Industrial Park Development: This development scenario can take the full advantage of certain interchanges as they are located in proximity to one or more major transportation facilities. For industrial park tenants, interchanges are very attractive locations because they effectively shorten supply chains, thus giving the tenants a competitive edge. Uncertainties associated with travel times for goods and services due to traffic congestion can be greatly reduced by locating industrial facilities in interchange areas. Local communities would also welcome locating industrial parks near interchanges as it minimizes the amount of semi-truck traffic on local roads and distance potentially noise and air polluting facilities away from residential areas.

Dr. Rohan Wickramasuriya is a Research Fellow at the SMART Infrastructure Facility, University of Wollongong, Australia.