CENSUS CARTOGRAPHY: THE KENYAN EXPERIENCE UN EXPERT GROUP MEETING ON CONTEMPORARY PRACTICES IN CENSUS MAPPING AND USE OF GEOGRAPHIC INFORMATION SYSTEMS UN HEADQUARTERS NEW YORK 29TH.

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Transcript CENSUS CARTOGRAPHY: THE KENYAN EXPERIENCE UN EXPERT GROUP MEETING ON CONTEMPORARY PRACTICES IN CENSUS MAPPING AND USE OF GEOGRAPHIC INFORMATION SYSTEMS UN HEADQUARTERS NEW YORK 29TH.

CENSUS CARTOGRAPHY: THE KENYAN
EXPERIENCE
UN EXPERT GROUP MEETING ON CONTEMPORARY
PRACTICES IN CENSUS MAPPING AND USE OF
GEOGRAPHIC INFORMATION SYSTEMS
UN HEADQUARTERS NEW YORK
29TH MAY TO 1ST JUNE 2007
PRESENTED
by
EMMA A.ODHIAMBO
KENYA NATIONAL BUREAU OF STATISTICS
Nairobi
[email protected]
INTRODUCTION

The first census was conducted in 1948,
followed by others in 1962, 1979, 1989 and the
most recent in 1999.

Kenya has been able to conduct censuses after
every ten years.

In the last three censuses Kenya has been able
to carry out cartographic census mapping of
the whole country.
INTRODUCTION CONT’D
 The
information collected
includes:
 Demographic
 Education
 Labour Force
 Housing and Sanitation
OBJECTIVES OF MAPS IN A
CENSUS
EA identification
 Assist in the delineation of the country
into units known as Enumeration Area
(EA)
 Assist enumerator to identify and plan
how to logically move within the EA
Omission and Duplication
 Maps ensure that errors of omission
and duplication are avoided
OBJECTIVES CONT’D
Budgeting
 Budgeting for other census related
requirements e.g personnel and
materials.
Data Dissemination
 Maps make it easier to analyze,
present and disseminate census
results
1969, 1979 and 1989 Censuses

1969 CENSUS
 Mapping activities done by Survey
Department, Ministry of Lands and
Settlement and Geography
department, University of Nairobi.
 Topographic maps cuttings used
(Scale 1:50,000)
 Very little field work done.
1979 CENSUS
 Efforts
made to improve on the 1969
census
 Creation of cartography unit in 1976
 Enumeration Areas were delineated
in the office.
 Attempt made to use satellite
imageries ( not successful)
1989 Census
Mapping drew heavily from 1979
experience and was considered a great
success
 The officers were trained locally and
abroad
 New concepts were introduced: Villages
 Household listing

1999 CENSUS MAPPING
Geographic frame
 Administrative structure
 Intercensal changes
 In Administrative units and
number of EAs

Number of Administrative
Units
Administrator
19692
19793
19894
19995
Administrative Units
President
Kenya
Province
1
1
1
8
Provincial Commissioner
8
Districts
Locations
Sub-Locations
Enumeration
Areas
8
8
District Commissioner
41
41
69
184
260
497
567
618
1,099
2,427
2410
3,111
3,553
6,612
20,000
25,000
36,979
61,921
41
Divisions
1
District Officer
154
Chief
Assistant Chief
Table: 1 Changes in the number of Administrative units between the last four
Censuses
FIELDWORK
 Training
workshops
(cartography,DSO & Provincial
Administration)
 Mapping teams
 Mapping
EA Delineation and EA size
 Dense
rural settlements(Agricultural
areas)
 Arid/ Semi Arid areas (Sparse
population)
 Urban ( High population density)
 EA size:- recommended is100
household (500 persons)
 Composite EAs
Scales

Rural Areas
 Dense rural settlments1:10,000,
1:20,000
 Sparsely populated areas 1:50,000,
1:100,000, 1:250,000
 Urban 1:1000,1:2,500 and 1:5,000
 District Maps
 1:100,000, 1:200,000
GEOCODING

Coding: Admin Unit No Digits
Sample code
 EA Type
 EAs 4
3010101010011
 Sub location
2
301010101
 Locations
2
3010101
 Divisions
2
30101
 Districts
2
301
 Provinces
1
3
 EA TYPE CODE
 Rural 1
Urban 2 Peri Urban 3
Numbering of EAS
Ground Verification
 Checking
of maps on the ground
before the census
 In the history of census taking in
Kenya
this was achieved in 1989
Constraints
Digital Mapping
 Late and erratic disbursement of funds
which results to shortage of time for
mapping
 Problem of urban slum mapping
 Use of sketch maps especially in urban
areas
 Shortage of skilled manpower
 Lack of up to date topographic maps

RECOMMENDATIONS
Early training of personnel in GIS/CAC
 Timely disbursement of funds
 Acquisition and use of satellite
imageries for urban areas (Quick Bird)
 Use of Geographic Positioning System
(GPS)

GEOGRAPHIC INFORMATION
SYSTEM (GIS)

The 2009 census will be the second
to be undertaken using computer
assisted cartography (CAC.)

The UNFPA provided support for the
establishment of a GIS facility which
was commissioned in 1998 and
envisaged to culminate into a fully
fledged Kenya Census Geographic
Information System
GIS Cont’d

However the implementation of the project
experienced a number of setbacks that led
to a slow pace in the process of preparing
the enumeration area maps.

As a result of the slackened pace, maps for
26 districts were prepared using the GIS
whereas the rest of the districts (43) were
prepared using the conventional
cartography.
CONSTRAINTS




Late acquisition and installation of the
GIS facility.
Lack of adequate skilled staff in
Computer assisted cartography
Inadequate software user licences
Poor maintenance of the GIS facility
CONSTRAINTS Cont’d



Servicing of equipment was not
adequate
Upgrading of software was tied to
maintenance service contract
The cost of maintenance service
contract was and still is very high. If
not on this contract you can not get
any upgrade on the new software
release
USE OF SATELLITE IMAGES IN MAPPING FOR THE
2009 KENYA POPULATION AND HOUSING CENSUS.


One of the biggest challenges facing
census mapping in the heavily settled
and un planned areas in Kenya is lack of
suitable base maps in terms of scale
and currency.
The heavily settled areas which are
mainly in urban areas are associated
with slums where the settlements
patterns are very dynamic with rapid
changes taking place
USE OF SATELLITE IMAGES/AERIAL
PHOTOGRAPHS IN CENSUS MAPPING
Cont’d

Current and very large scale maps
are therefore compulsory to enable
proper mapping and the creation of
suitable Enumeration Areas.

Unfortunately, those responsible are
not able to provide such maps when
required.
USE OF SATELLITE IMAGES IN CENSUS
MAPPING Cont’d

Such challenges are quite serious in
countries such as Kenya where about
60% of the urban populations live in
these heavily settled areas (Slums).

There is hardily any town in Kenya
which does not have slum settlements
and this underlines the seriousness of
the problem.
USE OF SATELLITE IMAGES IN CENSUS
MAPPING Cont’d

The above mentioned challenges
are quite serious in Kenya where a
high percentage of the population
lives in the slum areas.
USE OF SATELLITE IMAGES/AERIAL
PHOTOGRAPHS IN CENSUS MAPPING
Cont’d

Such challenges are quite serious in
countries such as Kenya where about
60% of the urban populations live in
these heavily settled areas (Slums).

There is hardily any town in Kenya
which does not have slum settlements
and this underlines the seriousness of
the problem.
USE OF SATELLITE IMAGES/AERIAL
PHOTOGRAPHS IN CENSUS MAPPING
Cont’d

In the censuses of 1989 and 1999, an
attempt was made to solve this problem
by relying on the preparation of sketches.

But after the censuses, the sketches
could not be relied on during the design of
NASSEP programs and in the conversion
of the EA maps into digital formats
especially after the 1999 census.
USE OF SATELLITE IMAGES/AERIAL
PHOTOGRAPHS IN CENSUS MAPPING
Cont’d

During the cartographic mapping for the
2009 Census, satellite images and aerial
photographs are being used so as to
address this problem.

These products were used in Kisumu
during the pilot mapping and they have
also been used during the phase one
mapping covering a lager part of Nyanza
province and which was concluded recently
USE OF SATELLITE IMAGES/AERIAL
PHOTOGRAPHS IN CENSUS MAPPING
Cont’d

The products have proved to be very
useful. They have enabled the preparation
of excellent maps of the covered towns

Indeed they offer a complete solution to the
problem sited above because the products
are very current and therefore enabling the
mapping of every part of any urban area
and at any desired map scale.
USE OF SATELLITE IMAGES IN CENSUS
MAPPING Cont’d

The maps produced are of very high quality
and accurate and therefore they will ensure a
complete and accurate coverage of the
census.

Further, because of their high quality and
accuracy, they will enable a better sampling
frame to be put in place since the urban
population can be demarcated precisely from
the rural population. This was not possible in
the last census as it later led into a gross
under quotation of the urban population
Legend
Part of Nyalenda B Sub-Location
Roads
Village boundary
Enumeration Area boundary
Buildings
KASIYUYU
EA name
315
Structure number
Joseph Msoba
318
Israel Church
194
±
195
196
F. G. Church
305
314
317
308
197
313
Kiosk
304
198
315
307
316
312
303
199
311
310
306
KASIYUYU
604010401047
300
200
251
M. Jobito
309
249
201
George Onyango
248
302
269
301
253
250
252
KASIYUYU 604010401049
202
247
268
270
272
245
267
273
244
207 209
211
218
212 213
219
278
208
221
604010401048
KASIYUYU
275
220
208
256
265
274
216
210
266
299
297
215
204
205
254
277
214
206
246
255
276
Kinyozi
298
203
243
257
264
242
237
223
236
275
294
279
235
228
280
293
296
281
292
232
259
262
285
235
258
231
234
239
289
288
230
260
291
290
229
238
240
0
295
227
0
241
263
226
222
284
282
233
261
283
287
0
0.03
0.06
0.12 Kilometers
Part of Nyalenda B Sub-Location
318
Joseph Msoba
Legend
194
Israel Church
±
Roads
195
Village boundary
Enumeration Area boundary
Buildings
196
F. G. Church
305
KASIYUYU
EA name
604010401049
EA number
314
317
308
197
313
Kiosk
304
198
315
307
316
312
303
199
311
310
200
251
306
309
M. Jobito
KASIYUYU
604010401047
249
201
George Onyango
248
302
269
301
253
KASIYUYU 604010401049
202
247
268
270
272
250
252
300
245
267
273
216
211
210
244
218
212
207 209
213
219
266
274
275
278
220
208
256
265
208
221
604010401048
KASIYUYU
297
215
204
205
254
277
299
214
206
246
255
276
Kinyozi
298
203
243
257
264
242
237
223
236
275
294
263
235
228
280
293
296
281
292
232
259
262
285
235
258
239
289
288
231
234
230
260
291
290
229
238
240
0
295
227
0
241
279
226
222
233
261
284
282
283
287
0
0.03
0.06
0.12 Kilometers
CONSTRAINTS



The cost of the images and shape
files is too high
The satellite images are usually not
current hence not giving the true
picture on the ground
The time taken to access the
images and to create shape file from
them is also too long