THE NIGERIAN TOPOGRAPHIC MAP DIGITALISATION INITIATIVE: 
CURRENT WORK 
F. O. AKINYEMI, Ph.D 
Department of Geography 
Obafemi Awolowo University 
Ile-Ife, Osun State 
bakin yem@yahoo.com 
Commission VI, WG VI/3 
KEY WORDS: Topographic map, Digitalisation, Spatial Databases, Revision 
ABSTRACT: 
The creation of the Nigerian National Topographic database (NNTD) from analogue 1:50,000 topographic map series 
started in the late 1990-ties. The NNTD, being undertaken by the Federal Surveys Department (FSD), is aimed at 
building a digital topographic database (map coverage) of the entire country. This topographic database is the base for 
the production of thematic maps that are needed, which cover a wide variety of topics (socio-economic, natural and 
cultural resources). It is widely accepted that to develop the urban and rural areas based on the principle of 
sustainability, the successful initiation as well as implementation of free market zones and privatisation process would 
require the existence of well-structured digital spatial databases. The initiative is very crucial in our national drive 
towards development, since however frantic our efforts are to investment, we can not succeed without up-to-date maps. 
This effort at digitalising existing topographic maps is long overdue as the crop of maps we have were published thirty- 
five years ago on average. The 1:50,000 topographic map series was published between 1966 and 1967 (aerial 
photography, ground control and compilation dating to 1956). There are two phases of the digitalisation effort. The 
first phase covers the digitization of all 1:50,000 topographic maps available on Nigeria. This initial phase does not 
include updating, but it is solely aimed at deriving a baseline topographic data framework, as there may be need for 
historical mapping. The second phase entails updating the topographic database. This paper describes the on-going 
effort at creating a baseline digital topographic database for Nigeria and considers the various constraints being 
currently experienced. 
1. INTRODUCTION the most frequently used of all Nigerian topographic 
maps (see Soneye, 1998). 
The first phase of digitalisation is the capture of 
topographic features on the 1:50,000 topographic map Table 1: State of Topographic Mapping in Nigeria 
series. It would have been expected that alongside the 
  
  
  
  
  
  
  
  
  
initial data capture of all topographic terrain features, Mapping Year No. of § No. of | Tota! 
: ; : Scales started | sheets | sheets coverage 
map updating would simultaneously be executed. It is published 
thought to be of importance to digitise the 1:50,000 maps 1:2,000,000 | =1965 100 % 
as they are, to serve as a baseline database, a framework 1:1,000,000 | =1965 100 % 
upon which to build subsequent databases and data 1:500,000 1952 16 16 100 9$ 
versioning. Database revision to reflect the dynamism of (old series) 
the terrain depicted, is to commence immediately data 1:500,000 1960 33 8 24.24 % 
capture is completed. (new series) 
1:250,000 1969 85 59 100 % 
Although Nigeria has several topographic map series at 1:100,000 1938 337 277 95 % 
various scales, there is no complete topographic map 1:50,000 1966/ 1352 1122 83.23 % 
coverage except at the scales of 1:2,000000, 1:1,000000, 1967 
1:500,000 (old series of 1952) and 1:250,000. Table 1 1:25,000 1981 5408 > % 
  
  
  
  
  
  
  
shows the state of topographic mapping in Nigeria. With Source: FMWH (1996), Olomo et. al (1998) and 
the technical assistance of the Canadian government, the Balogun (1999) 
1:50,000 topographic map series were produced in the 
late 1960-ties and has coverage of about 83 percent. The The cartographic data received from topographic maps, 
1:50,000 map series is the series being digitised as it is --- for the whole country would create the digital 
topographic (framework) database for comprehensive