Distr.: LIMITED
ECA/NRD/CART.9/ETH. 1 October 1996
Original: ENGLISH
Ninth United Nations Regional Cartographic Conference for Africa
Addis Ababa, Ethiopia 11-15 November 1996
CARTOGRAPHIC ACTIVITIES IN ETHIOPIA
Economic Commission For Africa
Ninth United Nations Regional Cartographic Conference for Africa 11-15 November 1996
Item 4 of Draft Provisional Annotated Agenda
CARTOGRAPHIC ACTIVITIES IN ETHIOPIA*
(SUBMITTED BY THE GOVERNMENT OF ETHIOPIA)
*By the Ethiopian Mapping Authority
ADDIS ABABA September 1996
Original: English
ECONOMIC COMMISSION FOR AFRICA
Ninth United Nations Regional Cartographic Conference for Africa
11-15 November 1996
Item 4 of draft provisional annotated Agenda
CARTOGRAPHIC ACTIVITIES IN ETHIOPIA*
(SUBMITTED BY THE GOVERNMENT OF ETHIOPIA)
Introduction
The Ethiopian Mapping Authority (EMA) is a government organisation with the responsibility for surveying, mapping and remote sensing activities in Ethiopia.
Despite a relatively limited number of staff EMA has the task of producing geo- information for a vast geographical area. This is both a great challenge and a driving force for the continuous development and rationalisation of the activities of the Authority. In addition to its task as the national provider of geo-information EMA must also be able to meet increasing customers demand for customised products which include digital spatial data.
The Ethiopian Government is increasing the demands on its agencies for efficiency in the provision of products and services and for an increased level of cost recovery. Donor agencies insist on the development of institutional sustainability. To meet these demands, and to maintain a competitive edge in the future, will call for continuous change, flexibility and adjustment to current demands and technological development. In order to maximise its use of manpower and technical resources EMA's approach to national mapping has been to give high priority to those parts of the country which are potentially rich in
natural resources.
Up to now, EMA has been able to follow up technological developments closely and to adopt the state-of-the-art geo-information technology which suits our local conditions and meets our specific needs and competence. Valuable assistance in the development of the Authority has been provided through the long-standing institutional co-operation between EMA and the National land Survey of Sweden (Swedesurvey). Impetus and support has also been provided through co-operation with other national and international organisations and training centres such as ITC in the Netherlands.
To keep abreast of developments in technology, organisational restructuring has been undertaken with the aim of effectively addressing and meeting changes in production methods and routines.
* Prepared by the Ethiopian Mapping Authority.
Marketing of products and services has been given more prominence: earlier less emphasis was given to customer services and marketing;, now customised products have become a key elements in the range of map products.
Comprehensive production-oriented training programmes have been conducted to enhance the technical knowledge and skill of EMA's staff. These programmes have been implemented both in-house and abroad. Whereas in previous years priority was given to technical training there has been a shift of focus to training within the management and administrative domains of the organisation.
Despite our efforts there is still much left to be done before we can fully satisfy users' demand for geo-information. There are many challenges ahead but the progress made in the last three years has given us a stable foundation on which we can continue to build for the future. EMA was very proud to be given the Dolezal Award at the 1996 ISPRS congress in Vienna as a recognition of its efforts.
Technology
EMA executes its tasks using a range of modern geodetic survey, photo laboratory, photogrammetric, cartographic, remote sensing and map reproduction equipment. Computer support, based on modern PCs and workstations in a local area network, is used on a rapidly increasing scale.
EMA is at an historic watershed namely, the transition from conventional to digital methods for the creation of databases and map production.
Main Activities
The status ofthe main activities carried out by the Authority is described below.
1. Primary Data Acquisition
Since 1957 wide angle aerial photography at scales of 1:40,000 and 1:50,000 has been carried out for the production of 1:50,000 and 1:250,000 scale topographic mapping. Since 1980 photography has been done on a planned, regular basis.
Large scale photography at scales between 1:8,000 and 1:20,000 has been flown for major towns, agricultural areas, hydro-electric dam sites, railway and highway construction projects. Between 1991-1995 photography covering an area of
55,000 km2 has been flown at the 1:50,000 scale augmenting the existing
relatively recent coverage of the country (see Annex 1). The small and large scale photographs are used for topographic mapping at various scales and for mosaicking and interpretation work. The small scale photography is flown by foreign firms under contract to EMA, whilst the large scale photography can be flown by a local organisation. Recently small scale photography has been flown with modern GPS navigation and camera operating systems that can determine the GPS coordinate of the projection centres in real time. Cross strips are flown to provide auxiliary data the adjustment of blocks.Satellite images such as Spot P and XS and Landsat-TM, are also used for
mapping and resource investigation. In all of these fields, the Authority provides consultancy services and controls the quality of primary data for the wholecountry.
2. Geodetic Surveys
To provide basic control data, the national geodetic network, consisting of first, second and third order points, has been extended to cover an area of
approximately 500 OOO.km . in regions which have a relatively high potential in natural resources (Annex 2)Extension and densification of the national control network is done on a
continuous basis, at an average rate of 30 000 km2 per year, using classical and
GPS survey methods. However, some isolated areas are mapped using local control, depending on the application of the end products. Geodetic control nets
are also extended as required to regions where large scale mapping and
engineering survey data are required. The control for these types of work are of second and third order which is adequate for isolated surveys for irrigation, hydroelectric dam construction, town planning and other related developmentschemes.
3. Topographic Mapping
The following methods are applied to produce different types of topographic data.
3.1 Conventional Line Mapping
Ethiopia is almost entirely covered by maps at the scale of 1:250,000 (see Annex 3). These maps were published between 1965-1972. Since there is a wide demand for maps at this scale, EMA started a map revision programme in 1993. Though a study of revision needs indicated that most of the sheets in the series were in need of revision, about 30 map sheets were considered to be of high priority. Revision
of these maps is planned to be carried out in two phases and at present the first
phase comprising 12 map sheets has been completed. The second phase, comprising the remaining 18 map sheets has already begun, based on a revised project document which reflects the experience gained during the execution of the first phase, and making use of the newly introduced digital technology. These changes will accelerate the revision programme.EMA's capacity for new small scale map production is mainly engaged in the production of the 1:50,000 national topographic map series. This mapping project was started in 1971 and, to date, about 50 % of Ethiopia has been covered based on the choice of priority area of socio-economic potential development (see Annex 4). About 18% of the coverage has been mapped since the 8th UN
Regional Cartographic Conference for Africa. The increase in speed is
attributable mainly to the use of orthophoto techniques.3.2 Orthophoto mapping using satellite imagery and GPS ground control
surveys
EMA has used orthophoto mapping to meet urgent customer needs in parts of the country where there is no line map coverage. Since development enterprises have sprouted all over the country, the demand for geo-information is, at present, increasing at a rate which has not previously been experienced. It was clear to EMA that all these needs could not be met using conventional methods and a decision was taken to use satellite imagery to create orthophotos. The ground control was to be provided using GPS surveying methods. This resulted in several successful contract mapping projects. The Sheraro Humera mapping project in Tigray is one example. It was carried out using SPOT imagery with GPS survey to produce 31 orthophoto map sheets at the 1:50,000 scale. Using the same methods 48 sheets were produced for the Abay-Tekeze watershed master plan preparation project. Unlike the previous project, the technology of Spatial Triangulation using SPOT data along with GPS survey was applied in this case.
3.3 Digital Data Capture
Digital data methods have been introduced to increase the flexibility of topographic information and in order to meet specific user needs. The software used includes Arc/Info and SOS-MAP. The creation of topographic database is partly being implemented by digitising existing line maps. All presentation work is done by applying computer assisted cartography.
Digital data capture from aerial photographs is also another source of data for the topographic databases. The data are collected from 1:50,000/1:40,000 aerial photographs using upgraded analogue and analytical photogrammetnc plotters using the SOS-MAP software and sent via LAN for further cartographic work.
4. The Development of Remote Sensing Techniques for Resource Studies
Remote Sensing technology has brought new opportunities for resource studies, change detection, land use applications and land cover mapping. Realising the potential benefits of this tool, EMA has established a Remote Sensing Department with the long term aim of expanding the services that can be provided to development-oriented ministries and agencies. To start with, the Authority has acquired some basic equipment, satellite imagery such as that of Landsat and SPOT. So far several pilot projects have been successfully executed, some for experimental purposes and others based on user demands. The Department has been strengthened with effectively trained manpower and the acquisition of an ERDAS system now upgraded to version 8.2, and the installation of two workstations for GIS and remote sensing in a LAN environment.
5. Thematic Mapping
In addition to £he topographic maps, thematic maps covering a wide range of topics are prepared including those based on geographic research for projects such as national and regional atlases. The multi-colour national atlas which includes over 70 topics already is under wide circulation. To date several thousand copies of the atlas have been distributed and EMA has received encouraging comments. Work on a geographic gazetteer to facilitate the location and identification of feature names is at an advanced stage of production. A database has been designed and digital recording oftoponomys has been started.
6. Manpower and equipment
Currently EMA has 344 employees of whom about 62% are technical staff. As stated earlier, training is given both in house and abroad depending on available
rsources.
Local training in surveying and mapping is given at EMA for concerned technical staff drawn from both EMA and user organisations. Up to now 387 trainees have participated in these training programmes. This training is an important bridge to strengthen the linkage of EMA with the users. In addition, EMA publishes a bulletin called "GIBE" which serves as a communication media mainly with user
organisations.
7. Equipment
EMA has a range of modern surveying, photogrammetric, remote sensing,
cartographic, photo laboratory and map reproduction equipment. Computerequipment includes work stations and wide selection of PC's. Despite these resources there is still a need for more equipment particularly at the end of the
digital map production line.Presently available equipment include:
Surveying: - Theodolites and levels
- Electronic distance measuring equipment for long and short ranges
- Radio communication outfit for field parties - GPS receivers
- Total station
Photogrammetry: - Analogue, PC-equipped, upgraded analogue and
analytical plotters such as A10, A8, B8s, PG2, C8BC2 and DSR 11/15
- Orthophoto equipment (OR1)
- Point transfer devices (PMG 2 and PUG4)
Cartography:
Photo laboratory:
Map Reproduction:
Remote Sensing:
Computer Services:
- Scribing and engraving tools and optical enlarger - Computerised type setting machine
- Arc/Info on workstations - SOSMAP on workstations - Digitisers
- Plotters
- Contact printers and vacuum frames for aerial photographs and manuscripts
- Process cameras
- Black and white and colour enlargers - Black and white and colour contact printer - Offset presses (single and double colour) - Monotype type setting machine
- Down printing frame
- Workstation with ERDAS Imagine software - Scanner
- PC with digitiser -Procom2
- Optical projector
- Diazo Exposure with developer - Spectro Radio Meter
- Interpretescope - Zoom Transferescope - Arc/Info workstation - PC based Map/Info - Film writer
- Micro computers with different architecture - 4d/66 LE Novell file server running Novell
Netware version 3.12
- Sun SPARC station 20 with multiprocessor architecture, server loaded with ARC/INFO 7.0.3 and ERDAS IMAGINE 8.2 based on a Unix X- windows environment
- Printers, plotters and other peripherals
7. Present Capability: Currently EMA renders services in the following
fields:
Survey: - Geodetic surveys
- Topographic surveys - Engineering surveys - Cadastral surveys - Survey somputations
- Data srocessing and dissemination to users Mapping: - Aerial photography and flight consultancy to
domestic user organisations - Processing of aerial photographs - Aerial triangulation and adjustment - Photogrammetric plotting
- Map printing by off-set printing machine - Orthophoto mapping
- Colour laboratory services
- Digital data capture using upgraded analogue plotters and analytical plotters
- Digitising
Atlas Preparation and Geographic Names Study:
- Preparation of thematic maps
- Preparation of regional and national atlases - Geographical studies and gazetteers
Remote Sensing: - Digital image processing
- Photo interpretation using aerial photos and/or satellite imagery
- Data analysis using remote sensing data and
imagery
- Data conversion from digital to analogue & vice-
versa
- Consultancy services to users Computer Services : - Systems administration
- System maintenance - Data management
- Hardware and software handling - Programming
- Installation
- Training and consultancy
8. Future activities
8.1 Technical Activities
As the situation regarding the basic map coverage at a scale of 1:50,000 shows, using a single basic scale or applying one standard map production method may not be feasible in the future. An alternative scale or method may have to be applied. Our experience so far has indicated that the use of satellite imagery is a fast and economical way of producing some types of maps at medium and small scales. This production method will continue to be used for mapping suitable
areas.
A speedy transformation to the use of digital mapping methods will be continued for both the new mapping and map revision programmes. This will include a further acceleration of the programmes through the introduction of digital orthophotos and the allocation of resources for the creation of topographic databases.
The introduction of new systems and the upgrading of old systems will also be an un-avoidable task in all technical production environments as long as the technology is suitable for the EMA environment and the necessary funds can be made available
8.2 Training of Manpower
The management of EMA is very conscious of the importance of continuous manpower training and development if the Authority is to meet the challenges of product development, Government demands for increased efficiency and higher levels of cost recovery. This requires training programmes across the full spectrum of the Authority's activities from senior management to technician. At present geo-information technology, of which mapping is a key component, is
changing with almost bewildering rapidity and it is difficult to estimate the life span of each of its components. To keep abreast of the technological innovation and growth, modem attitudes and a new open-mindedness amongst all of the staff are crucial. Efforts will be made to be intellectually prepared to meet the challenges ofthe future.
