Tuesday, 21 June 2016

Street Naming and Numbering in Ghana using what3words - An Overview

A large number of countries in the world have only a few streets and properties with an official street name or number. Ghana falls into this category. This results in significant obstacles for the efficient running of central / local government planning and services; the provision of utilities; mail; emergency services and commerce in general. As well as efficient operation of services, the ability to control and collect domestic and non domestic property tax is severely hampered.
In an attempt to address the issues raised above, I have been involved in a project to allocate official names for every street in Ghana together with an official address for every property. In Ghana, this involves naming and numbering roughly 1 million streets and 30 million properties. The remit of the project is to ensure the appropriate infrastructure is in place to maintain this data set and enable access to both public and private sector organisations.
The issues surrounding the project were significant. As very few streets and properties had an official address, the volume of naming and numbering was vast. The resources, both from a people and technical perspective, were limited. There was also a cultural and potentially more difficult problem to resolve due to the reluctance of local populations to conform to the imposition of names and conventions from any official body. People would often continue to use the local alias for a location even when official naming and numbering took place.

The project encountered numerous technical considerations. The use of long street names where official names had been allocated. Inconsistencies when abbreviations and punctuation were used.
The variety of dwellings also varied considerably; from the ordered ones in the more affluent areas to densely populated and chaotic ones in less affluent areas. Mixed dwellings where parts of the building were used for commercial purposes and part for residential were common.
 

This is part of a fairly striking set of buildings that make up the Villagio complex near the airport in Accra.
There were many instances of permanent and temporary structures being side by side. Temporary structures were sometimes wooden shacks selling goods; sometimes even metal containers. Most of these fell within our scope as they were still charged business rates and were potential clients for utility and other commercial providers.


There were countless alleyways, footpaths and squares across the most densely populated and compact areas, lined with both residential and commercial properties.
Given the numerous and varied issues, our approach to the project had to be carefully considered. We identified the positive aspects and tried to work that to our advantage. Above all, we had to be practical at every stage.
The lack of formal street naming and number meant we didn’t have to deal with multiple legacy conventions. Ghana also has very well defined, hierarchical spatial boundaries across the whole country. At the top level it has 10 regions, then districts, sub-metro and communities. It has a very well defined official street naming and numbering convention, however the implementation of these conventions was patchy. There were existing projects with national coverage that use addresses which could both contribute and benefit from our project. As in most of Africa, there is a very significant use of mobile phones and familiarity with mobile technology and conventions. There are some very clever people with the vision, drive and influence to resolve any problem.

Our key strategy was to use data from the National Waste Bin Distribution project. The aim of this project was to visit every household in Ghana to see if they required a bin collection service. As they were recording the GPS co-ordinates of every household using a mobile app, our project simply used this data to derive the properties and first approximation of streets. The streets were then improved on by more conventional means through a map digitisation project used by the bin collection service. We used our software, already developed for the UK market, to then allocate unique identifiers to streets, properties and addresses. This made the project very cost effective and quicker to implement.
Some core principles enshrined in the British Standard, BS7666, were used. This included using a Unique Property Reference, Unique Street Reference and the concept of a Land and Property Unit. The use of multiple addresses including alternates, provisional and historic was adopted, as well as the ability to hold multiple application cross references to enable efficient system integration.
The project then deviated from the British Standard by ditching certain conventions like postal addresses. New concepts like street aliases to cater for existing local names were introduced. This recognised the need to not impose official names, but to accommodate local ones so as not to alienate the local population. The adoption of the official names would be a gradual process when the benefit from receiving efficient services was realised. The unofficial locality information was included in the address to increase adoption. Both the streets and addresses inherited all the spatial characteristics associated with an address to avoid joining different types of data to realise the full address.
There was still a requirement for a postal code system even though no legacy system exists as in the UK. There was a debate on whether this was needed, but the prevalence of these types of codes and use in devices such as SatNavs swayed the argument. Rather than devise a completely new convention, we decided to adopt a 3 word address as generated by the award winning company what3words. What3words have invented an algorithm to describe each 3 by 3 metre grid on the planet by using a combination of 3 English language words. Each street segment is allocated its own 3 word address which acts as a post code. It is a “user friendly” way of defining any location on the earth. The Latitude and Longitude convention is anything but.
Another key part of the strategy was to focus on manageable areas and not tackle the whole country to start with. This enabled strategies, conventions and technical issues to be formulated and teething issues ironed out before applying them to a larger area. Prioritisation of areas such as the capital Accra also ensured maximum benefit as early as possible.

Lessons learnt in the UK also helped steer the project away from time consuming and costly initiatives. For example, the need for absolute geographical accuracy of all properties in Ghana is a massive undertaking. This level of accuracy isn’t required to generate a good set of street names and property numbers. Ultimately the presence of a consistent set of addresses is the primary driver for improvement and efficiency. Then using tried and tested conventions, techniques and software used in the UK, married with innovations such as those introduced by what3words will act as a catalyst to boost the provision of public services, commerce and the general well-being of the citizens of Ghana.