GEO-REFERENCING OF GENERAL BOUNDARIES USING
REAL-TIME KINEMATICS FOR THE IMPROVEMENT OF
LAND ADMINISTRATION IN KENYA
A case study of Kiambu-Kiambaa Registration section
(Kiambaa/Ruaka/5402)
By
MIKE KELVIN MUTHUMBA
REG NO: 113P01800
A project report submitted to the School of Surveying and Geospatial Sciences in
Partial fulfilment of the requirements for the award of the degree of:
Bachelor of Technology in Land Survey
MAY, 2015
2015
ii
DECLARATION
I hereby declare that this project is my original work and has not been presented in
any other university for examination or award of any other degree.
..
Mike Kelvin Muthumba
Reg No.EEGJ/01800P/2013
Supervisor
This project has been submitted for examination with my approval as the supervisor.
....
Dr. Samson O. Ayugi
iii
ABSTRACT
A General Boundary is an Approximate Boundary. It is a boundary of which the
precise line is undetermined in relation to the physical features which demarcate it.
In Kenya, general boundaries have very poor survey accuracy. Registry maps based
on these boundaries are unreliable. That notwithstanding, parcels of land in Kenya
acquired through the process of Land Consolidation/Land Adjudication are
registered using registry maps based on general boundaries. This has led to hundreds
of thousands of boundary disputes. Many boundary dispute cases generate other
cases such as destruction of property, physical body injuries and even murders.
In this study, the accuracy of Geo-referencing using GPS Real-Time Kinematic was
tested by comparing its data with that generated by a conventional land survey
method (traverse) where the results show that the computed RMS of the system is
within the expected accuracy.
It is concluded that the RMS results obtained deems it justifiable that RTK should be
embraced in Geo-referencing of general boundaries hence recommended that more
awareness be imparted to users on the new technology.
Geo-referencing ensures that; distances can be measured; areas can be calculated;
directions can be determined; exact position of any point can be determined;
geographical coordinates of a locality can be found; and parcels of land can be
identified without ambiguity
iv
DEDICATION
I dedicate this project first to the Almighty God who has granted me the strength and
the intellectual capacity to accomplish this project.
I also dedicate this project to my wife Mary Njeri Murage, my mother Jane Wanjiku
Mugia, George Kithinji Mugia (Uncle), Mary Muthoni Mugia (Aunt), my
Grandmother Florence Mabuti Mugia, friends and the former Director of Surveys
(Kenya) E M. Murage for his mentorship in this profession.
v
ACKNOWLEDGEMENT
I express my sincere gratitude to my supervisor Dr. Samson Ayugi, Chairman,
Department of Geo-information and Earth Observation, for his guidance, support and
encouragement that enabled the success of this project.
I feel indebted to the District Surveyor Kiambu, Mr Muchungu, for his assistance
with the equipment and materials used in the process of realizing this noble project.
My gratitude also goes to the entire staff School of Surveying and Geospatial
Sciences, Technical University of Kenya, for their continuous assistance and advice
regarding this project and my studies as a whole. In particular, I would like to thank
Dr.Wayumba for his wide scope of knowledge that was incorporated in this project.
Finally, I would like to give all the gratitude to the Almighty for giving me the
courage to face all the challenges that came by regarding this project.
vi
TABLE OF CONTENTS DECLARATION ................................................................................................................ ii
ABSTRACT ...................................................................................................................... iii
DEDICATION ................................................................................................................... iv
ACKNOWLEDGEMENT ................................................................................................... v
TABLE OF CONTENTS ................................................................................................... vi
LIST OF ABBREVIATIONS ............................................................................................ viii
CHAPTER ONE ................................................................................................................. 1
1.1Background to the Study............................................................................................. 1
1.2 Problem Statement .................................................................................................... 1
1.3 Overall Objectives ..................................................................................................... 1
1.5 Research Questions. .................................................................................................. 2
1.6 Scope of the project. ................................................................................................. 2
1.7 Organization of the Project ........................................................................................ 2
CHAPTER TWO ................................................................................................................ 3
GEO-REFERENCING OF GENERAL BOUNDARIES ...................................................... 3
2.1 Types of Cadastral Boundaries in Kenya .................................................................... 3
2.1.1 The Fixed Boundary ............................................................................................... 3
2.1.2 The General Boundaries ......................................................................................... 3
2.1.3 Origin of General Boundaries in Kenya .................................................................. 4
2.2 Land Adjudication and Consolidation ........................................................................ 4
2.3 General Boundaries and Land Disputes ...................................................................... 6
2.4 Surveying a General Boundary to Fixed Boundary Standards ..................................... 8
2.5 What is Geo-Referencing? ......................................................................................... 9
2.5.1 Geo-Referencing of General Boundaries ................................................................. 9
2.5.2 Why Geo-Reference General Boundaries in Kenya? ............................................. 10
2.5.3 Precision and Accuracy in Geo-Referencing General Boundaries .......................... 11
2.6 Use of GPS in Geo-Referencing .............................................................................. 12
2.6.1 Global Navigation Satellite System (GNSS).......................................................... 12
2.6.2 Global Positioning Satellite System (GPS) ............................................................ 13
2.7 Positioning Techniques ............................................................................................ 15
2.8 GPS Surveying Methods .......................................................................................... 15
2. 9. Procedure of Carrying out RTK-GPS Survey ......................................................... 16
2.9.1 Sources of Error in GPS Survey ............................................................................ 17
vii
CHAPTER THREE........................................................................................................... 19
METHODOLOGY............................................................................................................ 19
3.1 Location of the Site ................................................................................................. 19
3.2 Work Flow ............................................................................................................... 19
3.3 Reconnaissance ....................................................................................................... 20
3.4 Selection of New Points ........................................................................................... 20
3.5 Personnel Involved .................................................................................................. 21
3.6 Checking of the Instruments .................................................................................... 21
3.7 GPS Observations.................................................................................................... 21
3.8 Precautions Taken During Observation .................................................................... 23
3.9 Data Processing and Transformation ........................................................................ 23
3.9.1 Traverse observations ........................................................................................... 23
CHAPTER FOUR ............................................................................................................. 24
DATA FINDINGS AND ANALYSIS ............................................................................... 24
4.1 Result Analysis........................................................................................................ 24
4.2. Discussion of the Results ........................................................................................ 24
CHAPTER FIVE .............................................................................................................. 27
CONCLUSION ................................................................................................................. 27
5.1 Introduction ............................................................................................................. 27
5.2 Conclusions ............................................................................................................. 27
5.3 Recommendations ................................................................................................... 27
REFERENCES ................................................................................................................. 29
APPENDICES .................................................................................................................. 30
Appendix 1 Setting up and Initialization of the Base with the Rover (2014) ................... 30
Appendix 2 GPS coordinates displayed by word pad from text tab file (2014) ............... 31
Appendix 3 TRAVERSE FIELD NOTES ...................................................................... 32
Appendix 4 TRAVERSE COMPUTATION .................................................................. 34
Appendix 5 DEMONSTRATION OF PICKINGS AND CHECKS ................................ 35
Appendix 6 DEMONSTRATION OF PICKINGS AND CHECKS Const .................................... 36
Appendix 7 BOUNDARY DATA .................................................................................. 37
Appendix 8 COORDINATES TRANSFORMATION TO UTM ................................................ 38
Appendix 10 COORDINATES TRANSFORMATION TO UTM Cont .......................... 40
Appendix 11 Google Earth view of the plotted coordinates (2014) ................................. 41
Appendix 12 Google Earth Image of the Geo-referenced parcel ..................................... 42
viii
LIST OF ABBREVIATIONS
GPS Global Positioning System
RMS Root Mean Square
R.I.M Registry Index Maps
P.I.D Preliminary Index Diagrams
GNSS Global Navigation Satellite System
UTM Universal Transverse Mercator.
1
CHAPTER ONE
INTRODUCTION
1.1Background to the Study
After the enactment of the Land Registration Act 20121 and the Land Act, 2012, it
has become obligatory that all parcels of land throughout the country be geo-
referenced to the National Grid to standards acceptable in terms of accuracy and
precision to ensure compatibility with other documents as pointed out under Section
15(b) and 107(8) of the Acts respectively. Also article 155 (a,b,c) of Sessional Paper
No.3 of 20092 advocates for use of modern technology in survey and mapping such
as the GNSS and GIS to improve mapping standards in general boundary areas so
that they fit into a computerized system. There are also many boundary disputes
emanating from General boundaries which are difficult to solve since such
boundaries are not mathematically determined but based on estimation and biased
historical evidence of their position.
1.2 Problem Statement
Most land registration sections are under general boundaries and are hence captured
in the Registry Index Maps (R.I.Ms) and Preliminary Index Diagrams (P.I.D
s).These
areas are not adequately covered by Control Survey Network making it difficult to
Geo reference such parcels of land using the conventional survey methods.
1.3 Overall Objectives
The overall objective of this study is to Geo-reference5 General boundaries using
Real-Time Kinematics GPS and highlight the advantages it offers in comparison
to the conventional survey methods.
1.4 The specific objectives are to: 1. Identify various types of boundaries as provided for by the respective Acts.
1. Propose a method of Geo-referencing.
2. Apply the method in Geo-referencing the boundaries of the parcel of land in
question.
1 Land Registration Act,2012.AN ACT of Parliament to revise, consolidate and rationalize the registration of
titles to land, to give effect to the principle and objects of Devolved Government in land registration, and for connected purposes 2 A National Land Policy that was to guide the country towards efficient, sustainable and equitable use of land for prosperity and posterity.
2
3. To compare and analyse the results obtained using a conventional survey
method (traverse) for accuracy, reliability and precision.
3
4 1.5 Research Questions.
1. How could the Survey of Kenya (S.O.K)3 and other organizations use Real-
Time Kinematics in mapping to help optimize and improve mapping
standards in general boundary areas so that they fit into a computerized
system?
2. How is the Real-Time Kinematics approach different from the traditional
approach?
3. Are the accuracies achieved using Real-Time Kinematics within the
acceptable limits in relation to the traditional methods of providing control?
1.6 Scope of the project. This project was confined to identification of various types of boundaries and to
geo-reference the parcel of land in question using GPS, Real Time Kinematics and
analysing the data against that obtained using conventional methods (Traverse).
1.7 Organization of the Project The project is divided into five chapters as follows:
Chapter One introduces the subject, presents the problem statement, research
objectives, scope of the study and the organization of the project.
Chapter two addresses the subject of Geo-referencing of General Boundaries, types
of boundaries, Origin of General Boundaries in Kenya, Land Consolidation and land
Adjudication in Kenya, General Boundaries and Land Disputes and Application of
GPS in Boundary surveys.
Chapter Three deals with the methodology of data collection, categories of data
collected, and methods of analysis of the same.
Chapter Four focuses on data findings and Analysis. Where the results of the study
from data collected are presented and analyzed.
Chapter five is the final chapter of this project which highlights the conclusion of the
study, recommendations and areas of further research.
3 SOK refers to the department of Surveys in the Ministry of Lands. The department is responsible for all cadastral operations in Kenya.
3
5 CHAPTER TWO
GEO-REFERENCING OF GENERAL BOUNDARIES
2.1 Types of Cadastral Boundaries in Kenya
Kenya practices a legal cadastre, which is a state register containing information
about land parcels. This is supported by a detailed description of the parcel either in
the form of Registry Index Maps (RIMs) under RLA4 or Deed Plans under RTA
5.
The index maps or deed plans are the end products of cadastral surveys.
There are two classes of Cadastral surveys, which support the two boundary
systems in Kenya that is the fixed and general boundaries.
2.1.1 The Fixed Boundary
Surveys in this system are precise and are carried out under the provisions of the
Survey Act Cap 299 of the Laws of Kenya, which details how and by who are such
surveys carried out and approved. This is especially important as the Government of
Kenya guarantees titles to land. The fixed boundary system is one which has been
accurately surveyed so that any lost corner monument can be re-established
precisely from mathematical measurements. Monumentation for fixed boundary
surveys consist of coordinated beacons at the turning points of rectilinear
boundaries. Natural features such as rivers, roads, and ocean line, may also be
adopted as curvilinear boundaries. Most of the fixed surveys are carried out under
the Registration of Titles Act (RTA)
2.1.2 The General Boundaries
Are carried out in accordance with four other Acts i.e. The Registered Land Act
Cap 300, The Land Consolidation Act Cap 283, The Land Adjudication Act, Cap
284 and The Land (Group Representatives) Act Cap 287.
The term general boundary means that the exact location of the boundary is
undetermined but assumed to be represented by a visible physical feature such as
hedges, walls, rivers or streams, coastlines, or any physical feature that may be
found suitable for the definition of the position of the boundary. The concept of
general boundaries was introduced in Kenya in 1959 by the Native Lands
4 RLA refers to Registered Lands Act Cap 300(repealed) laws of Kenya. 5RTA refers to Registration of Titles Act Cap 281 Laws of Kenya(repealed)
4
Registration Ordinance and the registry map was intended to be used as the index
map [GoK, 1966: 70].
2.1.3 Origin of General Boundaries in Kenya
Cadastral surveying in Kenya may be traced to the establishment of a survey section
and the appointment of a chief surveyor in 1903 to superintend the demarcation and
survey of plots that had been alienated in Nairobi (Njuki, 2001). Major landmarks in
the cadastral survey reforms in Kenya are associated with the different land reform
programs initiated over the years.
Prior to the Second World War, the major land reform programs were the Land
adjudication at the coast and the European settlement on the white highlands.
Cadastral surveys concerned with alienating crown lands to the white community
were done under the provisions of the Survey Ordinance of 1923 and registered
under the RTA. These surveys were of very high standards, described land
unambiguously and resulted in very few boundary disputes (Njuki, 2009).
The other form of surveys was done under the provisions of the Land Titles
Ordinance of 1908 to demarcate and define the boundaries of both adjudicated and
unclaimed land at the coast. These surveys were done by compass and chain with
connections to very few control points and were slow, expensive and of low
accuracy. Certificate of titles were issued for all adjudicated lands and all unclaimed
lands reverted to the crown.
2.2 Land Adjudication and Consolidation
The period after the Second World War to shortly after Independence (1963) saw
land reforms focus on loosening control to land ownership for the Africans. A series
of recommendations, factors and events led to the Land Consolidation and
Adjudication programmes which were intended to transform from customary to
individual (Statutory Freehold) land tenure for Africans in regions categorized
similarly in this period as Trust Lands. The Land Consolidation programme which
involved adjudication and fragment gathering of small plot sizes, worked for some
time and the areas in which it was implemented are referred to as Consolidation
areas. Unfortunately, land acquisition through the process under the Land
Consolidation Act did not require precise boundary surveys but simply identification
The main and unique problem with land consolidation process is
finding space to place the consolidated fragments as one parcel of
land on the ground
5
by use of physical features and general agreement on boundaries among the owners.
This was the genesis of general boundaries to support land registration in Kenya.
(There are some areas in Kenya where land consolidation was started in the
1970s and to date (2015), there are still parcels of land in the air yet to find
space to land)
The land adjudication programme replaced the land consolidation programme and
abandoned the fragment gathering approach. This programme is still ongoing and the
areas in which it has worked are referred to as Enclosure areas (Wayumba, 1999).
6 Similarly, there were areas referred to as Rangelands commonly inhabited by
nomadic pastoral communities in which group ownership of land was preferred to
individual. Group ranches were then registered in the name of group representatives
on behalf of the rest of the group members under the provisions of the Land (Group
Representatives) Act Cap 287 of 19686.
Cadastral surveys in this period were thus concerned with this endeavour. In
consolidation areas, surveys were done to ascertain the sizes of individual fragments
and the general size of the adjudication section, to demarcate the replanned plots and
to produce the Demarcation Maps and the Registry Index Maps. The surveys were
done under the supervision of the Director of Surveys. In the enclosure areas,
surveys were carried out to map the property boundaries in the adjudication section
and to prepare the Preliminary Index Diagrams (PIDs).
These surveys involved identification of boundaries on unrectified aerial
photographs. In Rangeland areas, surveys involved identification of group ranch
boundaries on 1:50,000 topographic sheets and simple ground surveys to map the
missing boundaries (Njuki, 2001). They resulted in the preparation of Registry Index
Maps Range (provisional). In the period after independence, the major land reform
policy has been the conversion of communal land tenure in trust lands into individual
ownership through land adjudication, the transfer of land from the white settlers to
6 An Act of Parliament to provide for the incorporation of representatives of groups who have been recorded as owners of land under the Land Adjudication Act, and for purposes connected therewith and purposes incidental thereto
6
the native Africans through Land Settlement Programs1 and cooperative societies
and the transfer of land from group or company ownership to individual land tenure.
Cadastral surveys in the enclosure areas are as described above while surveys to
subdivide group ranches and cooperative/company farms are increasingly being
undertaken as per the provisions of the Survey Act Cap 299 of the laws of Kenya. In
all the settlement schemes, apart from the One Million Acre Scheme, surveys
involved demarcation and survey of plots by ground survey methods. In the One
Million Acre Settlement scheme, surveys were done by the Survey Department and
involved the preparation of topographical base maps at a scale of 1/2500,
demarcation of plots and preparation of the Registry Index Map by Photogrammetric
Methods (Njuki, 2001).Currently, majority of the cadastral surveys in Kenya, done
for purposes of first registration, change of lease, conveyance or any other may be
classified under two broad categories i.e. the fixed boundary surveys and the general
boundary surveys. These two survey categories seek registration under two main
registration legislations i.e. The RLA and the RTA.
2.3 General Boundaries and Land Disputes
Land disputes may arise from a wide range of different situations and are commonly
found where there is intense population pressure on land, where different types of
land use abut or overlap one another, and where boundaries are not well demarcated.
(Hussein, 1998).
1) Over access to pastoral resources and damage to crops between herders and
farmers;
(2) Over grazing and watering areas between different groups of herders;
(3) Where customary boundaries are poorly defined between neighbouring
communities, and between migrant and indigenous farmers;
(4) Where expanding cities place pressure on peri-urban areas between the urban
elites and peri-urban populations;
(5) Where population pressure reduces the sizes of holdings below uneconomic
levels; and;
7
(6) Where state allocations of land for forestry or large scale development schemes
conflict with customary landholders interests (Leonard, R., and Longbottom, J.,
2000)
In Kenya, most physical boundary features are simple hedges that easily get
destroyed if not well maintained. In the event that the physical boundary feature is
removed, destroyed or substantially altered (for example, the river changing its
course or the hedge fully destroyed or missing) it becomes extremely difficult to re-
establish the original boundary to acceptable accuracies.
In addition to poor survey applications, the complexity of implementing Land
Consolidation Act especially in fairly developed areas (the Act does not provide for
compensation for developments during relocations), corruption and the sensitivity
and emotive nature with which Kenyans hold land has led to hundreds of thousands
of land disputes, mostly boundary related that have clogged the courts. Some
disputes pass from generation to generation.
During the Swearing in of the members of the County Land Management Board
(CLMB), Meru County in October 2014;
The Honourable Justice Njoroge of the Meru High Court remarked; Many
boundary dispute cases mutate and generate other cases arising out of
destruction of property, physical injuries and even murders
The import of this then, is that the boundary dispute may take ages before it can be
resolved because; the murder case must be resolved first; then the succession process
follows; thereafter the property damages case is resolved; before finally addressing
the boundary dispute.
Francis Oriosa Orango V Joseph Mato Ngoko & another (2008) EKLR: A land
mark and intriguing case involving a general boundary that was re-established by
over four land registrars at different times between 1993 and 2008.This would have
taken less than an hour if the boundaries were Geo-referenced.(facts of the case
annexed)
In Kenya, since registry maps based on general boundaries are not reliable, any
boundary dispute relating to general boundaries should be solved by the land
8
registrar through arbitration. The law provides that, except where the boundary has
been fixed as per section 19 of the Land Registration Act (LRA) No. 3 of 2012,
any dispute concerning a parcel of land arising out of a general boundary shall be
determined by the Land Registrar after receiving evidence as to its boundaries and
situation as may be necessary [LRA sec 18(3)]. Notwithstanding the law, the land
registrar is often faced with difficult times in circumstances where the protagonists
cannot avail reliable witnesses; or in circumstances where the aggrieved party may
have bought the land but not lived on it and boundaries are destroyed or removed. In
such circumstances, the land registrar has barely two options; either to postpone the
case and order the protagonists to agree and demarcate the boundary (which the land
registrar can then witness and record), or request a surveyor to apply any techniques
(including rudimentary measurements) to mark the boundary on the ground which
the land registrar would then order the warring parties to adopt. Thereafter, the land
registrar would order the parties to maintain the boundary.
The law provides that, The maintenance of general boundaries (fences, hedges,
walls, stones, pillars, beacons or any other physical features) demarcating a parcel of
land shall be the responsibility of the proprietors of the parcels of land. The Registrar
may in writing, order which of the adjoining proprietors shall be responsible for the
care and maintenance of any feature demarcating a common boundary, and any
proprietor so ordered to be responsible for the care and maintenance of the boundary
feature allows the feature or any part of it, to fall into disrepair, be destroyed or
removed, commits an offence and is liable on conviction to a fine not exceeding two
hundred thousand shillings (USD 2,200) - (LRA sec. 20).
2.4 Surveying a General Boundary to Fixed Boundary Standards
The Land Registration Act (LRA) No. 3 of 2012 provides that for a general
boundary to be surveyed to fixed boundary standards there must be a request by a
land owner whose parcel of land is defined by the boundary, or if the Land Registrar
desires it necessary to have the boundary fixed. In either case, the Land Registrar
must issue a notice to all owners of parcels of land defined by the boundary intended
to be fixed to avail themselves at the site on an appointed day that the boundary is to
be fixed. The land owners must show proof that they are the registered owners of the
abutting parcels of land before the exercise of ascertaining the boundary on the
ground commences. The field exercise involves a surveyor, the Land Registrar and
9
the parcel owners walking along the boundary and ascertaining its existence; where
there is a dispute, it is sorted out. The surveyor places a boundary mark/monument
(beacon) at every corner of the boundary and subsequently surveys the boundary
marks precisely as provided for in the Survey Act. The Land Registrar takes notes
and keeps a record endorsed by all the land owners present during the exercise.
After the survey plan defining the fixed boundary is approved by the Director of
Surveys, the Land Registrar shall file the plan (survey plan) containing the necessary
particulars and make a note in the register that the boundaries have been fixed, and
the plan shall be deemed to accurately define the boundaries of the parcel (LRA sec
19)
While legal boundary points for fixed boundaries are marked with marks, that are
precisely surveyed, legal boundary points for general boundaries though marked
with physical features, remain undefined.
The legal responsibility of ascertaining any uncertainty on a general boundary is
vested with the Land Registrar while the determination of the position of any
uncertainty on a fixed boundary is vested with the surveyor (LRA sec 18(3).
(Muriithi, 2015)
2.5 What is Geo-Referencing?
To geo-reference is to define location in physical space and is crucial to making
aerial and satellite imagery useful for mapping. Geo-referencing explains how
position data (e.g., Global Positioning System (GPS)7 locations) relate to imagery
and to a physical location. Different maps may use different projection systems.
Geo-referencing tools contain methods to combine and overlay these maps with
minimum distortion. Using geo-referencing methods, data obtained from
observation or surveying may be given a point of reference from topographic maps
already available. Geo-referencing describes the process of locating an entity in 'real
world' coordinates.
2.5.1 Geo-Referencing of General Boundaries
General boundaries as has been introduced, define most of land property in Kenya.
They are found in all consolidation, enclosure and rangeland areas. The registration
10
in these areas is supported by either the Registry Index Maps (RIM) or the Interim
RIMs.
One major problem of general boundaries is that whenever the boundary is lost or a
dispute arises over it, the method of reestablishment leaves so many loopholes for
abuse.
The RLA provides that in cases of disputes, the Land Registrar after gathering all
views of the people resident in the area and any other relevant information
including that provided by the surveyor, decides the position of the disputed
boundary and his/her decision is final. It is noted that the RIM is not an authority on
boundaries and the opinion of the surveyor is just treated alongside all the other
views of the elders.
(Wayumba, 1999) Recommends, due to the inaccuracies associated with land
adjudication programs, the areas of parcels quoted in the title deeds are at variance
with the true physical area. This causes problems at the time of land subdivision for
sale or transfer and there is therefore an urgent need to fix general boundaries so as
to upgrade them to the RTA type of surveys.
7
2.5.2 Why Geo-Reference General Boundaries in Kenya?
There are a number of justifiable reasons why general boundaries in Kenya need to
be geo-referenced; they include and not limited to:
Unreliable Levels of Survey Accuracy: As indicated earlier in this paper,
many titles in Kenya acquired through the process of land adjudication are
based on registry maps whose general boundaries are not geo-referenced.
For this reason, any scaled distances or areas computed from these registry
maps do not reflect the distances or areas on the ground to reliable levels of
accuracy. Worse still, the registry maps cannot be used to guide in the
identification of the location of the parcels of land on the ground.
7 A satellite-based navigation system made up of a network of 24 satellites placed into orbit by the U.S. Department of
Defense. GPS was originally intended for military applications, but in the 1980s, the government made the system available for
civilian use.
11
Even a qualified surveyor cannot independently locate the parcels of land
shown on a registry map on the ground without the help of the land owners and,
or the local community
(Muriithi, 2015)
Boundaries in Arid and Semi-Arid Lands (ASAL): In the Arid and Semi-
Arid lands in Kenya, commonly referred to as ASAL areas, there exists no
prominent identifiable vegetative vegetation. As George Oner Ogalo (2002)
puts it, boundary hedges, even if planted (in these areas) cannot grow into
air visible boundaries (to be mapped for adjudication purposes) due to the
harsh conditions. In addition, the communities resident in these areas are
nomadic pastoralists who keep on moving from place to place during
different seasons in search of pasture and cannot maintain boundaries; and
even if it were possible for them to maintain them, they would not favour
hedges as boundaries because hedges restrict movement of their livestock
(Ogalo, 2002)
2.5.3 Precision and Accuracy in Geo-Referencing General
Boundaries There is a school of thought (in Kenya) that is of the view that geo-referencing of
general boundaries means transforming the general boundaries into fixed
boundaries. That is, surveying all the general boundaries with the same degree of
precision and levels of accuracy as provided in the survey Act, Cap 299 for fixed
boundaries.
The other school of thought propagates that geo-referencing is not fixing; that is,
whereas fixed boundaries are automatically geo-referenced; the converse is not the
same. When general boundaries are geo-referenced, it does not mean they have
been fixed; or that they must be fixed in order for them to be geo-referenced.
Fixed boundaries are automatically geo-referenced; but not all geo-referenced
boundariesare fixed (Muriithi, 2015)
P.Williamson quotes a resolution adopted at the U.N. Regional Cartographic
Conference for Asia and the Far East held in India in 1955 [19] which stated:
12
"The precision of a cadastral survey should not be more than necessary for the fulfillment
of practical requirements. The system, the method of production, and the legal basis
should be adapted to local circumstances both social and physical."
8 2.6 Use of GPS in Geo-Referencing
The days when a cadastral surveyor used to have six chainmen are gone. With the
advent of Total Stations and GPS- the black boxes that almost anyone can operate-
the surveyor will have to change his approach to surveying. There will be little need
for manual skills and more emphasis will be laid on management skills. (Njuki,
1998).
GPS has been designed to facilitate roaming through the so called Real Time
Kinematic Systems (RTK). This has made possible rapid point layout using these
systems. GPS accuracies are now in the region of 5 20 cm well within our
cadastral standards. (Yego, 1998)
GPS technology has been used in cadastral surveys in countries such as El
Salvador, Indonesia, Morocco, Botswana, Namibia, Jordan and in a number of
countries in Eastern Europe. Tests for use of GPS in RTK8 surveys in Belize and
Albania have demonstrated that the use of GPS in cadastral surveys has
considerable cost savings (Mwenda, 2001).
There is no doubt therefore about the potential of using GPS in Geo-referencing of
general boundaries.
2.6.1 Global Navigation Satellite System (GNSS)9
The GNSS consist of three main satellite technologies namely:
GPS,
Glonass and
Galileo. 9
Each of them consists mainly of three segments:
(a) Space segment,
(b) Control segment and
8
Real Time Kinematics (RTK) is a differential GNSS technique originated in the mid-1990s that provides high performance
positioning in the vicinity of a base station. 9 The term global navigation satellite system (GNSS) refers to a constellation of satellites providing
signals from space transmitting positioning and timing data. By definition, a GNSS provides global
coverage.
13
(c) User segment.
These segments are almost similar in the three satellite technologies, which are all
together make up the GNSS. As of today, the complete satellite technology is the
GPS technology and most of the existing worldwide applications related to the GPS
technology. The GNSS technology will become clearer after the operation of Galileo
and the reconstruction of Glonass in the next few years.
However GPS has been widely used in positioning due to its wide coverage.
2.6.2 Global Positioning Satellite System (GPS)
The United States Department of Defence (DoD) has developed the Navstar GPS,
which is an all-weather, space based navigation system to meet the needs of the USA
military forces and accurately determine their position, velocity, and time in a
common reference system, anywhere on or near the Earth on a continuous basis
(Wooden, 1985).
GPS has made a considerable impact on almost all positioning, navigation, timing
and monitoring applications. It provides particularly coded satellite signals that can
be processed in a GPS receiver, allowing the receiver to estimate position, velocity
and time (Hofmann-Wellenh of et al., 2001).
There are four GPS satellite signals that are used to compute positions in three
dimensions and the time offset in the receiver clock. GPS comprises three main
components namely:
Space segment:
The space segment (SS) is composed of the orbiting GPS satellites or Space Vehicles
(SV) in GPS parlance. The GPS design originally called for 24 SVs, eight each in
three approximately circular orbits, but this was modified to six orbital planes with
four satellites each. The six orbit planes have approximately 55 inclination (tilt
relative to Earth's equator) and are separated by 60 right ascension of the ascending
node (angle along the equator from a reference point to the orbit's intersection).
The orbital period is one-half a sidereal day, i.e., 11 hours and 58 minutes so that the
satellites pass over the same locations or almost the same locations every day. The
orbits are arranged so that at least six satellites are always within line of sight from
almost everywhere on Earth's surface. The result of this objective is that the four
satellites are not evenly spaced (90 degrees) apart within each orbit. In general terms,
14
the angular difference between satellites in each orbit is 30, 105, 120, and 105
degrees apart which sum to 360 degrees.
Orbiting at an altitude of approximately 20,200 km (12,600 mi); orbital
radius of approximately 26,600 km (16,500 mi), each SV10
makes two complete
orbits each sidereal day, repeating the same ground track each day. This was very
helpful during development because even with only four satellites, correct alignment
means all four are visible from one spot for a few hours each day. For military
operations, the ground track repeat can be used to ensure good coverage in combat
zones.
Control segment.
The control segment is composed of:
1. Master control station (MCS),
2. An alternate master control station,
3. Four dedicated ground antennas, and
4. Six dedicated monitor stations.
User segment. The user segment is divided into three parts: i.e.
a. The military.
b. The civilian Surveyors, Engineers, Tourists, security personnel, and
sports just to state but a few.
c. Receivers-there are three common types of GPS receivers i.e.
Navigation receivers-are used mainly for reconnaissance due to their
accuracy. Uses the C/A Code.
Geodetic Receivers-used for precise work since they accommodate post
processing
Real-Time receivers-similar to geodetic receivers. In addition have a
radio- link which aid in communication with another receiver 10
10SV-Satellite Vehicle
15
2.7 Positioning Techniques
There are three GPS positioning techniques namely:
a. Absolute point positioning.-involves a single receiver measuring its range
to at least four satellites simultaneously. This positioning method is the least
accurate and not applicable for survey work.
b. Relative positioning.-when two or more receivers are tracking at least four
satellites simultaneously .this method attains higher accuracy than absolute
positioning. There is extensive correlation between observations taken from
the same satellites at the same time and at separate stations.
c. Differential Positioning. -Similar to relative positioning but requires at
least one receiver to be placed on a known station.
2.8 GPS Surveying Methods
1. Rapid static Surveying-observations are made within a base length less
than 20km.length of the session ranges from 5-30 minutes. This method
allows post-mission processing.
2. Static Surveying-Observations are made between base lengths greater than
20Km.its used in densification of controls in a large area. The session ranges
from 30 minutes to 2hrs.
3. Kinematic Surveying-the receivers are often in motion compared to
startic.In Kinematic Survey ,Initialization16
of the receiver and maintenance
of lock to all the satellites is required. Kinematic survey involves the
following:
Kinematic on the fly: it provides instantaneous positioning since the
receiver is in motion throughout the session. Its most productive and
less accurate.
Stop and Go. One stationary referred to as the reference and a
moving receiver referred to as the rover are used. The reference
occupies the same control point throughout the session.
Leap frog method: To receivers are used, where one receiver moves
at a time.
16
Pseudo-Kinematic method: This method is a high bread of static
and kinematic surveying methods.
2. 9. Procedure of Carrying out RTK-GPS Survey
To carry out a GPS survey, the following are the minimum areas that should be
considered.
Planning
Reconnaissance.
Observations.
Planning: -This is done to ease the process of surveying together with the level of
accuracies required. Planning is done to ensure that:
a. The Datum points are selected from a network that is geometrically correct.
b. There is security for both manpower and instruments.
c. There are enough datum points.
d. There are enough GPS receivers to be used.
Reconnaissance:-It entails checking the layout of the land in terms of:
a. Accessibility.
b. Vegetation cover.
c. Presence of tall building.
d. Transmission lines.
e. Plus any other factor that may cause obstruction.
Observations:-This is the actual field work where the GPS observations are made
on both old survey points and the new survey points.
Figure 2.1 RTK GPS Surveying
(www.what-when-how.com)
17
In this method, the base receiver remains stationary over the known point and is
commonly attached to a radio transmitter (Figure 2.1).
The rover receiver is normally carried in a backpack (or mounted on a moving
object) and is attached to a radio receiver. Similar to the conventional kinematic GPS
method, a data rate of 1 Hz (one sample per second) or lower is normally employed.
The base receiver measurements and coordinates (along with the antenna height) are
transmitted to the rover receiver through the communication (radio) link. The built-in
software in the rover receiver combines and processes the GPS measurements
collected at both the base and the rover receivers to obtain the rover coordinates.
The initial ambiguity parameters are determined almost instantaneously using a
technique called on-the-fly (OTF) ambiguity resolution.
2.9.1 Sources of Error in GPS Survey
The GPS is not a perfect system. There are several different types of errors that can
occur when using a GPS receiver, for example: User mistakes
User mistakes account for most GPS errors; and a GPS receiver has no way to
identify and correct these mistakes.
User mistakes:-Satellite may be blocked by buildings, terrain, electronic
interference, and sometimes dense foliage. A GPS receiver needs a fairly clear
view of the sky to operate.
Multipath interference: Multipath interference is caused by the satellite signal
reflecting off of vehicles, buildings, power lines, water and other interfering
objects Multipath is difficult to detect and sometimes impossible for the user to
avoid or for the receiver to correct. When using a GPS receiver in a vehicle
place the external antenna on the roof of the vehicle to eliminate most signal
interference caused by the vehicle. If the GPS receiver is placed on the
dashboard there will always be some multipath interference.
Satellite and receiver clock errors:-These can be slight discrepancies in the
satellites atomic clocks which may cause slight position errors in the GPS
receiver. Errors are monitored and corrected by the Master Control Station.
Orbit errors:-Satellite orbit pertains to the altitude, position, and speed of the
satellite. Satellite orbits vary due to gravitational pull and solar pressure
18
fluctuations. Orbit errors are also monitored and corrected by the Master
Control Station.
Satellite geometry:-The location of GPS satellites in relation to a GPS receiver
on the ground can impact the receivers ability to triangulate a 3D position. The
quality of a receivers triangulated position improves the further apart GPS
satellites are located from each other in the sky above the receiver. The quality
decreases if the satellites are grouped close together in the sky above the
receiver.
Atmospheric interference:-The atmosphere can slow or speed up the satellite
signal. Fortunately, error caused by atmospheric conditions (ionized air,
humidity, temperature, pressure) has been reduced with the implementation of
the Wide Area Augmentation System (WAAS)11
11 Selective Availability:-Selective Availability is the intentional degradation
(limits accuracy of satellite signals) of the GPS system by the U.S. Department
of Defense for security reasons.
(Control Survey notes, Jane Maina, KISM 2010)
11 WAAS is an extremely accurate navigation system developed for civil aviation. Before WAAS, the
U.S. National Airspace System (NAS) did not have the potential to provide horizontal and vertical
navigation for approach operations for all users at all locations. With WAAS, this capability is a
reality. The Wide Area Augmentation System (WAAS) is an air navigation aid developed by the
Federal Aviation Administration (prime contractor Raytheon Company) to augment the Global
Positioning System (GPS), with the goal of improving its accuracy, integrity, and availability.
Essentially, WAAS is intended to enable aircraft to rely on GPS for all phases of flight, including
precision approaches to any airport within its coverage area.
19
CHAPTER THREE
METHODOLOGY
3.1 Location of the Site
The project area is within Kiambu County, Kiambaa Sub-County The site is about
300 Metres off Nairobi-Limuru by pass road junction.
3.2 Work Flow
Figure 3.2 Flowchart showing a summary of the methodology
Data Analysis &
presentation
Reconnaissance
Identification of old points
Selection of new points
GPS -RTK Survey
Checking instruments
GPS Observation
Traverse Survey
Checking instruments
Traverse Observations
20
3.3 Reconnaissance
Existing Survey plans and R.I.Ms of the area bearing (Kiambaa/Ruaka/sheet 13) and
544/77 were obtained from Survey of Kenya. The RIM showed the extent the parcel
of land in question. While the Survey plan showed a number of existing old control
points which were used to extend control to the site using the conventional survey
method (Traverse).
With the plans, the surveyor visited the site and made a general view of the ground.
A thorough search for the beacons in the field was done. The general boundaries
defining the parcel Kiambaa/Ruaka/5402 were located and found to be properly
maintained and undisputed.
The old points found were;
Point -Northing -Easting
TW9 129497.17 18705.48
TR19 134134.17 23755.43
TR11 134027.29
23669.66
Figure 3.3 coordinates of beacons used as reference points
A topographical map was used to I identify their plannimetric position while their
coordinates were obtained from FR No 544/77 & FR No.130/47
All the control points selected were found to be in good condition and on stable
ground.
3.4 Selection of New Points
The following factors were put into consideration while selecting the new control
points.
Stability of the ground: Stability of the ground where the points were placed was
of much consideration as the points could be used later in detail picking.
Therefore they were placed on stable ground to ensure that their positions and
elevation does not change.
Accessibility: Points were placed in such a way that they could be easily
accessed and that they could not be easily found by unauthorized persons to
21
avoid interference. Accessibility was also based on the time factor such that
less time could be used when moving from one station to the next.
Maximum coverage: Points were established in such a way that they covered
the area of interest effectively.
Once the location the location of the new points was established, they were marked
by iron pins hammered into the ground, concreted and witnessed with nearby
features for ease of recognition in future.
3.5 Personnel Involved
Since survey field work cannot be carried out by one person, the surveyor recruited
some assistants to help carry out the exercise.
3.6 Checking of the Instruments
Before going to the field, the instruments were individually checked to ensure that all
the instruments were in the right working conditions and all accompanying
instruments and accessories were available and in good condition.
3.7 GPS Observations
The GPS receivers were checked a day before the field day to be certain whether
they were functional. It was also ensured that the batteries were fully charged.
The instruments used included;
GPS Base Station receiver (1)
GPS Rover receiver (1)
Memory cards (2)
Measuring tape (1)
Panga (1)
Booking sheets & field notes.
Iron pins.
Control points used in RTK-GPS observations were approximately 10KM from the
site (i.e. in Kiambu Town) hence the test how efficient RTK-GPS Geo-referencing
can be in areas where controls are scarce or none at all. The following formed part of
the initial setup.
22
Base Station- The base station was set at one second collection rate and at 13
degrees elevation mask. While ensuring that there was no obstruction to the sky. The
datum coordinates were keyed into the receiver which were in the local system
(Cassini soldner)
The Rover- The rover receiver was set at one (1) second collection rate and 15
degrees elevation mask. The rover rod was at a fixed height. Unlike conventional
surveying from a total station, the line of sight was not needed.
Before getting too far away from the base station, the radio link to the rover was
checked. The first thing to be done upon starting the survey on the data collector
was to initialize the system (resolve the integer ambiguity).
A Known point initialization was done this is the fastest and safest way to
initialize. Where possible and practical this should be the method of choice. The
firmware uses the three-dimensional deltas of the relative WGS84 positions of the
base stations and the known point occupied by the rover as an aid in solving the
integer ambiguities.
After initialization the data was compared with the first and second shots to within
an acceptable tolerance. The points checked, hence preceded with data collection
with the confidence of surveying with a correct initialization. This procedure was
repeated whenever there was any loss of lock
The system was now ready to observe points that required to be geo-referenced. The
amount of time of occupation varied depending on conditions such as obstruction,
multi-path and noise.
Observations started at 8:00Am and went as follows.
One GPS receiver was set at control point TW9 at 8:00 to run unstopped
throughout the observation period (Base station), since the point was on
stable ground and for security purposes (see Appendix 1).
The other receiver (Rover) was used to establish new points & Geo-reference
the corner points of the boundary of the parcel of land under study. The
23
Rover continuously received corrections from the Base station while at the
same time ensuring that lock was maintained and ambiguity fully resolved.
3.8 Precautions Taken During Observation
The following precautions were taken in to consideration to make the project a
success.
The batteries were frequently checked during observation period.
Instrument height was read at the beginning and at the end of the observation.
The cut off angle was raised or lowered depending with the features
encountered in the field.
The tripods screws were fastened properly.
The real time Nothings and Eastings were booked before the observations were
stopped at each instrument station.
3.9 Data Processing and Transformation
There was no post processing of data since the actual coordinates were obtained in
real time and transferred as text tab document using Bluetooth technology to the
computer. The Data collected was in Cassini a local system and hence was
transformed to UTM coordinates to facilitate plotting it on Google Earth as
KML/KMZ file for further checking and scrutiny. (See Appendix 2, 3 and 4)
3.9.1 Traverse observations
A traverse was also done between control pointsTR19&TR11using F/R
No.544/77.where the new points established by GPS were also coordinated from the
traverse to acquire a set of coordinates for comparison and analysis. A high accuracy
was achieved which was deemed justifiably accurate enough to provide a control
network for this project.using the traverse network the boundary of the parcel was
picked to acquire a set of data for analysis.
The drawings were also exported to Google earth for appreciation.
24
CHAPTER FOUR
DATA FINDINGS AND ANALYSIS
4.1 Result Analysis
This chapter represents the results of the project and their presentation with a view
to demonstrate the RMS error of the Geo-referenced land boundaries using Real-
Time Kinematics as compared with Geo-referenced parcel boundaries using
conventional survey method(Traverse).
4.2. Discussion of the Results
Statistics for the coordinates recorded by RTK and from the Traverse. This was
done by computing the coordinates difference for the points (northing and easting),
square of the points, and average of the squared difference and then computation of
the RMS error.
Computation of sample statistics that would be used to draw conclusion about the
Accuracy of Real-Time Kinematics was done utilizing the following equations in
Ms-excel 2007:
x2 = (X1-X2)2 ............Equation 1
y2= (Y1-Y2)2 ........Equation 2
RMS (E) = (Mean X2+Mean Y2) ....Equation 3
Where: X1=easting from the RTK- GPS
Y1=northing from the RTK -GPS
X2=easting from the Traverse
Y2=northing from the Traverse.
Mean X =average of easting squares of the residual
Mean Y =average of northing squares of the residual
N= number of the used points
25
Table 4.2 the table of computed RMS from the points defining the boundary of the
parcel in question.
Coordinates from RTK-GPS Coordinates from the
TRAVERSE
DIFFERENCE SQUARE
PID EASTING NORTHING EASTING NORTHING x y x2 y2 POINT
MK1 252623.6116 9867198.7790 252623.6016 9867198.7784 0.0100 0.0006 0.000100 0.000000 0.0100
MK2 252631.2454 9867215.6330 252631.2404 9867215.6297 0.0050 0.0033 0.000025 0.000011 0.0060
MK3 252595.2018 9867209.4490 252595.2038 9867209.4481 0.0020 0.0009 0.000004 0.000000 0.0022
MK4 252601.8965 9867225.8940 252601.8935 9867225.8938 0.0030 0.0002 0.000009 0.000000 0.0030
AVERAGE 0.000138 0.000011
RMS 0.0122
26
Figure 4.3 the graphic representation of residuals.
MK1 MK2 MK3 MK4
dN 0.0006 0.0033 0.0009 0.0002
dE 0.01 0.005 0.002 0.003
DIFFERENCE IN (M) 0.01 0.006 0.0022 0.003
0
0.002
0.004
0.006
0.008
0.01
0.012
DIF
FER
ENC
E (
M)
Graphic Representation of residuals
27
CHAPTER FIVE
CONCLUSION
5.1 Introduction
The objectives of this study were to analyse and test the suitability of the use of
Real Time Kinematic GPS in Geo-referencing of general boundaries with the view
of recommending the same for adoption and subsequent implementation. It is
therefore expected that when the government is ready to implement The Land
Registration Act, 2012, the results of this study will be found useful.
5.2 Conclusions
This project is sui generis and leaves no iota of doubt that there is dire and forthwith
need to geo-reference general boundaries in Kenya. The need is overwhelming not
only from surveyors but very many other land users such as valuers, estate agents,
architects, engineers, the government and even the general public, res ipsa loquitur.
In view of the foregoing, this study draws the following conclusions:
There are two types of boundaries established by various repealed Acts in
Kenya i.e. General and Fixed Boundaries.
THAT RTK GPS establishes boundary positions as accurately as the
conventional methods hence a near ideal method of Geo-referencing.
THAT RTK is economical and fast in geo-referencing of boundaries as
compared to the conventional methods.
THAT the Geo-referenced boundaries can be re-established in future if
damaged.
5.3 Recommendations
It is now a legal requirement in Kenya that all land for purposes of registration
or compulsory acquisition shall be geo-referenced (LA sec 8, 107(8); LRA sec
7(1)(d), 15). It is therefore not a matter of choice but to comply with the law.
The National Mapping Agency should establish a unitary and homogeneous
network of control points of adequate density, preferably using dynamic
technology such as GNSS.
28
The Survey Act (cap 299) and the medieval Survey Manual should be amended
to allow the use of modern technology such as GPS and GIS in authentication
surveys.
The Director of Surveys should work towards the establishment of Continuous
Operating Reference Stations (CORS) across the country as infrastructure to the
County Governments and private practitioners for mapping.
A new National Land Policy to be formulated which should advocate for the
use of the GPS in mapping.
29
REFERENCES
Government of Kenya, 2009: Sessional Paper Number 3, 2009 on National Land
Policy. Government Printer Nairobi.
Njuki, A. K., 2001. Cadastral Systems and their Impact on Land Administration in
Kenya. Proc. Int. Conference on Spatial Information for Sustainable Development,
Nairobi, Kenya, 2nd -5th October, 2001.
Bo Shen, 2009 GIS and GPS Technology, 0360-520, Seminar Report
Mwenda, J.N. 2001: Spatial Information in Land Tenure Reform with Special
Reference to Kenya. Proc. Int. Conference on Spatial Information for Sustainable
Development, Nairobi, Kenya, 2nd- 5th October, 2001.
Kaufmann, J. and D. Steudler, 1998: Cadastre 2014. A Vision for a future Cadastral
System.FIG Commission 7.
The Land Registration Act, 2012.(Kenya)
Maina J. 2010: Unpublished Third Year Control Survey Lecture Notes, Kenya
Institute of Survey and Mapping (KISM), Department of Surveying, Nairobi,
Kenya.
Yego, 1998. Modern Technology in Surveying: Opportunities and Challenges.,
1998.
Wikipedia encyclopedia, 2011 at http:// www.spacenews.com, May 2014
Network RTK Positioning at http://gpsworld.com 2014.
Real Time Kinematics article at http://en.wikipedia.org/wiki/Real_Time_Kinematic
Grooves, P.D., 2008. Principles of GNSS, Inertial, and Multi-sensor Integrated
Navigation Systems.
J.C, M.C., 1985. Surveying. 2nd ed.
sickle, J.V., 2008. GPS for Land Surveyors.
30
APPENDICES
Appendix 1 Setting up and Initialization of the Base with the Rover (2014)
31
Appendix 2 GPS coordinates displayed by word pad from text tab file (2014)
32
Appendix 3 TRAVERSE FIELD NOTES
33
34
Appendix 4 TRAVERSE COMPUTATION
35
Appendix 5 DEMONSTRATION OF PICKINGS AND CHECKS
36
Appendix 6 DEMONSTRATION OF PICKINGS AND CHECKS Const
37
Appendix 7 BOUNDARY DATA
38
Appendix 8 COORDINATES TRANSFORMATION TO UTM
39
Appendix 9 COORDINATES TRANSFORMATION TO UTM Cont!
40
Appendix 10 COORDINATES TRANSFORMATION TO UTM Cont
41
Appendix 11 Google Earth view of the plotted coordinates (2014)
42
Appendix 12 Google Earth Image of the Geo-referenced parcel