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1CVS 445: WATER RESOURCS ENGINEERING 1
Assessment: Course work 30% Final examination 70%
Course work schedule:CAT I:24/02/2005CAT II: 31/04/2005Course
Assignments: 17 /02/2005 submit on 10/03/2005
COURSE OUTLINE
1. Definition of Integrated Water Resources Management and
development (IWRD/M)2. Why Integrated Water Resources Management3.
Dublin principles4. Water users and implication of change5.
Integrated sustainable development in Water Resources engineering
(WRE) process of
change6. Water interaction and balance7. Catchments based
planning /management8. Legal & institutional framework and
international obligation for IWRM9. Kenya in focus, National water
campaign, Water ACT 200210. Introduction to WRE
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2INTEGRATED WATER RESOURCES MANAGEMENT
Introduction to Integrated Water Resources Management
(IWRM/D)Challenges faced by more and more countries in their
struggle for economic and socialdevelopment are increasingly
related to water. Water shortages, quality deterioration and
floodimpacts are among the problems, which require greater
attention and action. These concerns aregiving credence to the
concept of Integrated Water Resources Management (IWRM) as a
processto deal with water issues in a cost effective and
sustainable way. But what does integrated waterresources management
mean? Why is it so important? What are we losing without it? What
arethe gains to be made from introducing it? If it is so good, why
isnt everybody doing it already?
What is Integrated Water Resources Management (IWRM)IWRM has
neither been unambiguously defined nor has the question of how it
is to beimplemented been fully addressed. However, we can define
Integrated Water ResourcesManagement (IWRM) as a participatory
planning and implementation process, based on soundscience, to
determine how to meet society's long-term needs for water resources
whilemaintaining essential ecological services and economic
benefits. In other words, it is a process,which promotes the
coordinated development and management of water, land and
relatedresources in order to maximize the resultant economic and
social welfare in an equitable mannerwithout compromising the
sustainability of vital ecosystems.IWRM helps to protect the worlds
environment, foster economic growth and sustainableagricultural
development, promote democratic participation in governance, and
improve humanhealth. Worldwide, water policy and management are
beginning to reflect the fundamentallyinterconnected nature of
hydrological resources, and integrated water resources management
isemerging as an accepted alternative to the sector-by-sector,
top-down management style thathas dominated in the past.
In light of the foregoing a few points can be raised with
respect to IWRM;
The basis of Integrated Water resources Management (IWRM) is
that different usesof water are interdependent, hence the need to
consider the different uses of watertogether. Integrated water
resources management is a systematic process for the
sustainabledevelopment, allocation and monitoring of water resource
use in the context of social,economic and environmental objectives.
At its simplest, integrated water resourcesmanagement is a logical
and intuitively appealing concept. Its basis is that the many
differentuses of finite water resources are interdependent. That is
evident to us all. High irrigationdemands and polluted drainage
flows from agriculture mean less freshwater for drinking
orindustrial use; contaminated municipal and industrial wastewater
pollutes rivers and threatensecosystems; if water has to be left in
a river to protect fisheries and ecosystems, less can bediverted to
grow crops. There are plenty more examples of the basic theme that
unregulateduse of scarce water resources is wasteful and inherently
unsustainable
Integrated management means that all the different uses of water
resources areconsidered togetherWater allocations and management
decisions consider the effects of each use on the others.They are
able to take account of overall social and economic goals,
including the achievementof sustainable development.
IWRM & participatory decision makingThe basic IWRM concept
has been extended to incorporate participatory
decision-making.Different user groups (farmers, communities,
environmentalists) can influence strategies forwater resource
development and management. That brings additional benefits, as
informedusers apply local self-regulation in relation to issues
such as water conservation and
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3catchments protection far more effectively than central
regulation and surveillance canachieve.
Deliberate management of resources is needed to ensure long-term
sustainableuse...
Management is used in its broadest sense. It emphasises that we
must not only focus ondevelopment of water resources but that we
must consciously manage water developmentin a way that ensures long
term sustainable use for future generations.
IWRM is a systematic processIntegrated water resources
management is a systematic process for the sustainabledevelopment,
allocation and monitoring of water resource use in the context of
social,economic and environmental objectives. It is different from
the sectoral approach appliedin many countries...When
responsibility for drinking water rests with one agency, that of
irrigation water witha different one and responsibility for the
environment with yet another, there result lack ofcross-sectoral
linkages leading to uncoordinated water resource development
andmanagement, resulting in conflict, waste and unsustainable
systems.
WHY IWRM?
The Facts:
Of the Global water sources, 97% is seawater, and 3% is
freshwater. Of the freshwater87% is not accessible, meaning only
13% of freshwater is accessible, a mere 0.4% ofthe total!
Today more than 2 billion people are affected by water shortages
in over 40 countries. 263 river basins are shared by two or more
nations; 2 million tonnes per day of human waste are deposited in
water courses Half the population of the developing world are
exposed to polluted sources of water that
increase disease incidence. 90% of natural disasters in the
1990s were water related.
It is evident that the worlds freshwater resources are under
increasing pressure, and the increasein numbers of people from 6
billion to 9 billion will be the main driver of water
resourcesmanagement for the next 50 years. Hence IWRM is driven by
the recognition of water as vital forhuman survival, health and
dignity and a fundamental resource for human development.
Growth in population, increased economic activity and improved
standards of living lead toincreased competition for and conflicts
over the limited freshwater resource. A combination ofsocial
inequity and economic marginalisation forces people living in
extreme poverty lead tooverexploit of soil and forestry resources,
with damaging impacts on water resources.Here are a few reasons why
many people argue that the world faces an impending water
crisis:
Water resources are increasingly under pressure from population
growth, economicactivity and intensifying competition for the water
among users;
Water withdrawals have increased more than twice as fast as
population growth andcurrently one third of the world's population
live in countries that experience medium tohigh water stress;
Pollution is further enhancing water scarcity by reducing water
usability downstream; Shortcomings in the management of water, a
focus on developing new sources rather than
managing existing ones better, and top-down sector approaches to
water managementresult in uncoordinated development and management
of the resource;
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4 More and more development means greater impacts on the
environment; Current concerns about climate variability and climate
change demand improved
management of water resources to cope with more intense floods
and droughts.
PRINCIPAL COMPONENTS OF IWRM
Managing water resources at the basin or watershed scale. This
includes integratingland and water, upstream and downstream,
groundwater, surface water, and coastalresources.
Optimising supply. This involves conducting assessments of
surface and groundwatersupplies, analysing water balances, adopting
wastewater reuse, and evaluating theenvironmental impacts of
distribution and use options.
Managing demand. This includes adopting cost recovery policies,
utilizing water-efficienttechnologies, and establishing
decentralized water management authorities.
Providing equitable access to water resources through
participatory and transparentgovernance and management. This may
include support for effective water usersassociations, involvement
of marginalized groups, and consideration of gender issues.
Establishing improved and integrated policy, regulatory, and
institutionalframeworks. Examples are implementation of the
polluter-pays principle, water qualitynorms and standards, and
market-based regulatory mechanisms.
Utilizing an intersectoral approach to decision-making, where
authority formanaging water resources is employed responsibly and
stakeholders have a share in theprocess.
Water management PrinciplesA meeting in Dublin in 1992 (The
International Conference on Water and Environment, Dublin,Ireland,
January 1992.) gave rise to four principles that have been the
basis for much of thesubsequent water sector reform.
Fresh water is a finite and vulnerable resource, essential to
sustain life, development and theenvironment
Water development and management should be based on a
participatory approach, involvingusers, planners and policymakers
at all levels.
Women play a central part in the provision, management and
safeguarding of water. Water has an economic value in all its
competing uses and should be recognised as an
economic good
i. Fresh water is a finite and vulnerable resource, essential to
sustain life, development andthe environment.
Since water sustains life, effective management of water
resources demands a holistic approach,linking social and economic
development with protection of natural ecosystems.
Effectivemanagement links land and water uses across the whole of a
catchment area or groundwateraquifer.The notion that freshwater is
a finite resource arises as the hydrological cycle on average
yields afixed quantity of water per time period. This overall
quantity cannot yet be altered significantly byhuman actions,
though it can be, and frequently is, depleted by man-made
pollution. Thefreshwater resource is a natural asset that needs to
be maintained to ensure that the desiredservices it provides are
sustained. This principle recognises that water is required for
manydifferent purposes, functions and services; management
therefore, has to be holistic (integrated)and involve consideration
of the demands placed on the resource and the threats to it.The
integrated approach to management of water resources necessitates
co-ordination of therange of human activities, which create the
demands for water, determine land uses and generate
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5waterborne waste products. The principle also recognises the
catchment area or river basin as thelogical unit for water
resources management.
ii. Water development and management should be based on a
participatory approach,involving users, planners and policymakers
at all levels.
The participatory approach involves raising awareness of the
importance of water among policy-makers and the general public. It
means that decisions are taken at the lowest appropriate level,with
full public consultation and involvement of users in the planning
and implementation of waterprojects.Water is a subject in which
everyone is a stakeholder. Real participation only takes place
whenstakeholders are part of the decision-making process. The type
of participation will depend uponthe spatial scale relevant to
particular water management and investment decisions. It will
beaffected too by the nature of the political environment in which
such decisions take place.A participatory approach is the best
means for achieving long-lasting consensus and commonagreement.
Participation is about taking responsibility, recognizing the
effect of sectoral actionson other water users and aquatic
ecosystems and accepting the need for change to improve
theefficiency of water use and allow the sustainable development of
the resource. Participation doesnot always achieve consensus,
arbitration processes or other conflict resolution mechanisms
alsoneed to be put in place. Governments have to help create the
opportunity and capacity toparticipate, particularly among women
and other marginalised social groups. It has to berecognised that
simply creating participatory opportunities will do nothing for
currentlydisadvantaged groups unless their capacity to participate
is enhanced.
iii. Women play a central part in the provision, management and
safeguarding of waterThis pivotal role of women as providers and
users of water and guardians of the livingenvironment has seldom
been reflected in institutional arrangements for the development
andmanagement of water resources.Acceptance and implementation of
this principle requires positive policies to address womensspecific
needs and to equip and empower women to participate at all levels
in water resourcesprogrammes, including decision-making and
implementation, in ways defined by them.It is widely acknowledged
that women play a key role in the collection and safeguarding of
waterfor domestic and in many cases agricultural use, but that they
have a much less influentialrole than men in management, problem
analysis and the decision-making processes related towater
resources. The fact that social and cultural circumstances vary
between societies suggeststhat the need exists to explore different
mechanisms for increasing womens access to decision-making and
widening the spectrum of activities through which women can
participate in IWRM.IWRM requires gender awareness. In developing
the full and effective participation of women atall levels of
decision-making, consideration has to be given to the way different
societies assignparticular social, economic and cultural roles to
men and women. There is an important synergybetween gender equity
and sustainable water management. Involving men and women
ininfluential roles at all levels of water management can speed up
the achievement ofsustainability; and managing water in an
integrated and sustainable way contributes significantlyto gender
equity by improving the access of women and men to water and
water-related servicesto meet their essential needs.
iv. Water has an economic value in all its competing uses and
should be recognised as aneconomic good.
Within this principle, it is vital to recognise first the basic
right of all human beings to have accessto clean water and
sanitation at an affordable price. Yet Water has a value as an
economic goodas well as a social good. Many past failures in water
resources management are attributable tothe fact that the full
value of water has not been recognised and has led to wasteful
andenvironmentally damaging uses of the resource.Treating water as
an economic good is an important means for decision making on the
allocationof water. This is particularly important when extending
supply is no longer a feasible option.
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6Water has a value as an economic good as well as a social good.
Many past failures in waterresources management are attributable to
the fact that the full value of water has not beenrecognised. In
order to extract maximum benefits from available water resources,
there is a needto change perceptions about the value of water.Value
and charges are two different things and we have to distinguish
clearly between valuingand charging for water.The value of water in
alternative uses is important for the rational allocation of water
as a scarceresource, whether by regulatory or economic
means.Charging (or not charging) for water is applying an economic
instrument to supportdisadvantaged groups, affect behaviour towards
conservation and efficient water usage, provideincentives for
demand management, ensure cost recovery and signal consumers
willingness topay for additional investments in water
services.Treating water as an economic good is an important means
for decision making on the allocationof water between different
water use sectors and between different uses within a sector. This
isparticularly important when extending supply is no longer a
feasible option.In IWRM, economic valuation of alternative water
uses gives decision makers important guides toinvestment
priorities. It should not though be the only consideration. Social
goals are importanttoo. In a water-scarce environment, would it be
right, for example, that the next water resourcedeveloped should be
assigned to a steel-manufacturing plant because the manufacturer
canafford to pay more for the water than the thousands of poor
people who have no access to safewater? Social, economic and
environmental goals all play a part in IWRM decision-making.
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7PROCESS OF IMPLEMENTING IWRMThe overall objective of IWRM is to
lay the foundation for rational and efficient framework formeeting
the water needs for development, social and environmental uses. The
strategyencompasses institutional reforms that separate the
functions of;
Water service delivery, Management and administration Policy and
regulation
The process of implementing IWRM is really a challenge to
conventional practices. The case forIWRM is strong indeed
incontestable, but the problem in most countries is the long
history of uni-sectoral development. In this respect IWRM is a
challenge to convectional practices, attitudes andprofessional
certainties. It confronts entrenched sectoral interests and
requires that the waterresource be managed holistically for the
benefits of all.
All this implies change, which brings threats as well as
opportunities. There are threats to peoplepower and position; and
threat to their sense of themselves as professionals. IWRM require
thatplatform be developed to allow different interest groups top
negotiate their differences andsomehow nonetheless work
together.
IWRM requires reforms and obviously on step-by-step basis, where
some changes take placeimmediately and others needing several years
of planning and implementation.
Integrated water resources management is as concerned with water
demand as with its supply.Thus integration can be considered as
integration of natural systems with its vital role of
resourceavailability and quality and human systems, which
fundamentally determines the resource use,waste production, and
pollution of the resource. Traditionally, water managers viewed
their roleas that of meeting demand that is externally determined.
IWRM approaches should assist inshaping demand e.g. in terms of
quality, availability, peak demand.
The process of integrated water resourced management involves
integration of variousmanagement aspects namely;
Integration of Land and water managementAn integrated land and
water management is d departure form the hydrological cycle
oftransporting water between compartments air, soil, vegetation,
surface and groundwater sources.As a result, land use developments
and vegetation cover influence the physical distribution andquality
of water and must be considered in the overall planning and
management of the waterresources. This integration process also
takes into account the water is a key determinant of boththe
terrestrial and aquatic ecology. Catchment and basin level
management is not only importantas a means of integrating land use
and water issues, but is also critical in managing therelationships
between quantity and quality and between upstream and downstream
waterinterests.
Integration of quality and quantity in water resources
managementWater resources management entails the development of
appropriate quantities of water with anadequate quality. Water
quality management is thus an essential component of IWRM.
Thedeterioration of water quality reduces the usability of the
resource for downstream users. Clearly,institutions capable of
integrating the quantity and quality aspects have to be promoted
toinfluence the way human systems operate in generating, abating
and disposing of wasteproducts.
Integration of surface and groundwater managementThe
hydrological cycle calls for integration between surface and
groundwater management. Thedrop of water retained at the surface of
a catchment may appear alternately as surface and
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8ground water on its way downstream through the catchment. Large
sections of the worldpopulation depend on groundwater.
Integration of cross-sectoral and upstream downstream dialogueA
critically important role of IWRM is the integration of various
sectoral views and interest in thedecision making process, with due
alternatives given to upstream downstream relationships.The
consumptive losses upstream will reduce river flows. The pollution
loads dischargedupstream will degrade river water quality. Land use
changes upstream may alter groundwaterrecharge and river flow
seasonality. Flood control measures upstream may threaten flood
dependent downstream such conflicts of interest must be considered
in IWRM with fullacknowledgement of range of physical and social
linkages that exist in complex systems.Recognition of downstream
vulnerability to upstream activities is imperative
Integration of Freshwater and coastal zone managementFreshwater
and coastal zone management should be integrated, reflecting the
inter-relationshipbetween the two. Freshwater systems are important
determinants of conditions in the coastalzone and hence freshwater
managers should consider the requirements of the coastal zone
whenmanaging water resources. This is a special case of the
upstream-downstream issue, which isreceiving increased
attention
Integrating water and wastewater managementWater is renewable
and reusable resources. Where use is non-consumptive and returned
afteruse, mechanisms are needed to ensure that wastewater flows are
useful addition to resourceflows or water supply. Without
co-ordinated management, waste flows often simply reduceeffective
supplies by impairing water quality and increasing future costs of
water supply.Incentives for reuse can be provided to individual
user but to be effective reuse opportunitieshave to be designed
into the political, economic, social and administrative
systems.
In a nutshell the process of IWRM needs to recognise and pursue
social, economic and naturalconditions:Economic efficiency in water
use: water must be used to maximise efficiency with mind
thescarcity of water and financial resources, the finite and
vulnerable natures of water resources,and increasing demand upon
it.
Equity: basic right of all people to have access to water of
adequate quantity and quality forsustenance must always be
safeguarded
Environmental and ecological sustainability: Present use of
water must not be managed in away that will undermine the life
support system thereby compromising future users of water.
Water users Agriculture Water supply & wastewater Mining,
industry Environment Fisheries Tourism Energy Transport
Each of the water uses identified above has valuable positive
and negative impacts.Negative impacts which may be made worse by
poor management practices
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9PrioritiesEach country has its priority developmental and
economic goals set according to environmental,social and political
realities.
Social and economic benefits from water use sectors.These are
generally obvious in terms of food production, energy production,
drinking water, jobs,recreation, etc, but the relative value of
these benefits is more difficult to assess
Prioritising allocation between sectors...When there is
competition for water resources it brings into the open the need to
justify theallocation of water to one user rather than to another.
This value assessment should take intoaccount both the benefits and
the negative impacts. The input from users, politicians and
societyin general is necessary as the allocation may not be most
efficient when valued in economic termsalone or acceptable when
made only on political grounds
ENVIRONMENT Maintenance of functioning of ecosystems
Terrestrial and aquatic ecosystems need water to maintain their
functioning: plants evaporate andtranspire water; animals drink
water; fish and amphibians need water to live in. Water is alsoused
by upper-watershed ecosystems, downstream, wetlands, floodplains,
and mangroves needfreshwater inputs. This water is used to maintain
a (semi)-natural dynamic, often of a seasonalnature. To prevent
degradation and destruction of ecosystems, it is important to have
enoughwater of the right quality and with the right seasonal
variability.
Loss of environmental maintenance in return means the loss of
free environmental benefits fuelwood, water, fisheries, fruits.
They can also contribute to ecosystem degradation through
over-exploitation. That is why it is important that user
communities are involved in water managementdecisions.Natural
ecosystems provide many goods and services (functions) to humankind
that are oftenneglected in (economic) planning and decision
making.
Regulation functions Habitat functions Production functions
aesthetic functions
AGRICULTURE Impact of agriculture on the environment is of major
importance
The agriculture sector is most important as a user of water and
has heavy impacts. Abstraction ofwater for agriculture is leading
to dried up rivers, falling ground water tables, salinated soil
andpolluted waterways. Carefully considered multipurpose projects
can combine irrigation withaquifer recharge, land drainage and
ecosystem sustenanceURBAN WATER USESUrban water uses, in particular
wastewater effluents, pollute downstream ecosystems if
notsufficiently treated. The treatment of effluents is often costly
and, especially in developingcountries, not considered a high
priority given other needs. Effluent recycling and reuse are
oftenseen to be cost-effective conservation measures.
HYDROPOWERHydropower sector affects water regime by changing the
water and sediment regime and blockingmigratory movements of fish
and amphibians. In some cases reservoirs have provided newhabitats
for animals and investments have been made in environmental
protection upstream.Combining considerations of power generation,
flood control and ecosystem protection can meannew operational
rules for reservoir releases.
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INDUSTRYIndustry affects water quantity and quality. Industry
often has substantial impacts on waterresources downstream through
water use and pollution. Mining, for example, has affected
manywaterways in Latin America. In Western Europe industrial
pollution has taken its toll on aquaticecosystems during the last
century. In many developing countries management of industrialwaste
is not yet in place.
Barriers for implementation of IWRM Lack of awareness
Lack of awareness among all water users is the biggest obstacle
to change
Lack of political willLack of political will to combat vested
interests is also an important barrier. Often theinterests that
prevail are not necessarily the most critical ones.
Lack of human and financial resourcesLack of human and financial
resources causes integrated water resources management notto be
taken into account in planning and development
Implication for change
Recognition of sector needsMajor requirement of IWRM water
sector reform is to provide recognition of varying needs
andincorporate them in planning e.g. domestic, industrial and
agricultural water users.
Legislative adaptationsNational legislation often needs to be
harmonised and strengthened to provide vehicle forimplementation of
IWRM. Too many conflicting arrangements hinder adoption of IWRM
Institutional adaptationsWater institutions need to function
more and more as brokers between various other governmentand
stakeholders, rather than stand-alone units. Change in
institutional framework must allowcooperative management and
negotiation of water rights
Capacity buildingThe above requires a substantive capacity
building in facilitation, mediation, negotiation andsurveillance.
At present, both users and professionals are often not well
equipped to take onthese responsibilities as they require knowledge
and skills beyond those traditionally taught to anengineer or
hydrologist
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11
Water sector reforms in Kenya
Kenya is classified a water scarce country with an annual per
capita of about 685 m3. Against thisbackground, several problem
persist, these include Catchments degradation; Drying up of Rivers,
Receding of lake levels, Heavy siltation in dams and pans meant for
both hydropower generation and water supplies, Deterioration of our
water qualities, Increased water use conflicts due to competition
of the little available water resources, Damaged roads, railway
lines, bridges, buildings, farmland, water intakes and people
displaced
due flash floods,
In addition the levels of water services provision were faced
with problems including; Lack of adequate and continued dwindling
financial resources in the water sector, Dilapidated infrastructure
and low revenue collection to augment and maintain the existing
water supplies and to extend the water coverage, Increasing
number of people unserved in urban and rural areas and, Absence of
autonomous institutions to manage water supply and sewerage
services in our
cities and most urban areas.
The Water Act 2002 was developed with mind of facilitating the
management of the countrys waterresources in a sustainable manner
and ensue access to adequate water supply and sewerage by
thepopulation.
Until the water reforms were implemented the laws in existence
were inadequate becauseo there were too many legal provisions
dealing with Water, often conflicting, hence difficulties in
enforcemento Many different actors, whose activities conflict,
and no mechanism for resolutionso Ministry of Water handled policy,
regulation and service provision, hence no distinction
between water resources management, development and service
provisiono A supply-driven environment, with serious consequences
on sustainability and efficiency of
usage of the resourceo The overlapping roles and
responsibilities of key public actors in the water sector were
the
main causes of conflicts and poor services in the sector
The management strategy under the water Act 2002 allowed for
creation of the Water Services Boardto oversee the supply of water
and sewerage services while the management of the water
resourceswas vested on an autonomous Water Resources Management
Authority.
The Water Act 2002 therefore provides for separation of roles
and clarifies entitlement policy formulation that remains with
government ministry responsible for water regulation and management
of water resources and service provision devolved to autonomous
bodies participation of users through the water users
association and catchments advisory
committees Decentralization of water resources management and
service provision to drainage areas.
The Water Resources Management Authority manage, protect and
conserve our water resources
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12
The authority have regional offices at the catchments level for
decentralized decision makingfor quick response to water resources
management problems and to speed the waterallocation process along
the river basin equitably.
The Water Services Board Regulator for water services as
licensees, responsible for the efficient and economical
provision of water services by engaging an agent or water
service provider to give waterservices within its area of
jurisdiction.
Agents include Local Authorities or public water companies
formed for that purpose, privatecompanies, community organizations
or NGOs
Catchment Area Advisory Committees (CAACs) and Water users
Association
Ensure community participation in both the management of the
resources and development.
CAACs advise the WRMA at the appropriate regional office
concerning: Water resources conservation, use, and apportionment
The grant, adjustment, cancellation or variation of any permit
Water Users Associations serve as forum for conflict resolution
as well as co-operativemanagement of the resource in catchment
areas
Water Appeals Board An independent body to resolve disputes
between holders of water rights and the others.
Water Services Trust Fund To assist in financing the provision
of water services to areas of Kenya which are without
adequate water services in particular the poor communities
Polic
yFo
rmul
atio
nR
egul
atio
nSe
rvic
ePr
ovis
ion
MWRMD NWCPC MoLG SHG/NGOs MoALD
Irrigation
LAs
Conflicts on lead in policy formulation
Con
flict
s on
che
cks
and
bala
nces
Con
flict
s on
allo
catio
nof
reso
urce
s
Con
flict
s on
che
cks
and
bala
nces
Poor services
Polic
yFo
rmul
atio
nR
egul
atio
nSe
rvic
ePr
ovis
ion
MWRMD NWCPC MoLG SHG/NGOs MoALD
Irrigation
LAs
Conflicts on lead in policy formulation
Con
flict
s on
che
cks
and
bala
nces
Con
flict
s on
allo
catio
nof
reso
urce
s
Con
flict
s on
che
cks
and
bala
nces
Poor services
Graphical representation of the management structure under old
water laws
Core problems: Inadequate and insufficiently harmonized legal
and institutional frameworks Overlapping responsibilities
Inefficient operational and financial management systems
Institutional /management conflicts
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15
INSTITUTIONAL SET-UP UNDER WATER ACT 2002
.MoW Po
licy
Form
ulat
ion
Reg
ulat
ion
Serv
ices
Prov
isio
n
Nat
iona
l lev
elR
egio
nal
leve
lLo
cal l
evel
Con
sum
p-tio
n, U
se
Water and Sewerage ServiceWater Resources Management
Water AppealBoardWAB
WaterServices
RegulatoryBoardWSRB
WaterResources
ManagementAuthorityWRMA
WaterServicesBoardsWSBs
CatchmentAreas Advisory
CommitteesCAACs
Water ServicesProviders
WSPs
Consumers, Users
Water ResourcesUser Associations
WRUAs
Water ServicesTrust Fund
WSTF
RegionalOffice
WRMA
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THE WATER BALANCEThe water balance is an accounting of the
inputs and outputs of water. The water balance of a place,whether
it be an agricultural field, watershed, or continent, can be
determined by calculating the input,output, and storage changes of
water at the Earth's surface. The major input of water is
fromprecipitation and output is evapotranspiration. The geographer
C. W. Thornthwaite (1899-1963)pioneered the water balance approach
to water resource analysis. He and his team used the water-balance
methodology to assess water needs for irrigation and other
water-related issues.
To understand water-balance concept, we need to start with its
various components:Precipitation (P). Precipitation in the form of
rain, snow, sleet, hail, etc. makes up the primarilysupply of water
to the surface. In some very dry locations, water can be supplied
by dew and fog.Actual evapotranspiration (AE). Evaporation is the
phase change from a liquid to a gas releasingwater from a wet
surface into the air above. Similarly, transpiration is represents
a phase change whenwater is released into the air by plants.
Evapotranspiration is the combined transfer of water into theair by
evaporation and transpiration. Actual evapotranspiration is the
amount of water delivered to theair from these two processes.
Actual evapotranspiration is an output of water that is dependent
onmoisture availability, temperature and humidity. Think of actual
evapotranspiration as "water use", thatis, water that is actually
evaporating and transpiring given the environmental conditions of a
place.Actual evapotranspiration increases as temperature increases,
so long as there is water to evaporate andfor plants to transpire.
The amount of evapotranspiration also depends on how much water is
available,which depends on the field capacity of soils. In other
words, if there is no water, no evaporation ortranspiration can
occur.Potential evapotranspiration (PE). Potential
evapotranspiration is the amount of water that would beevaporated
under an optimal set of conditions, among which is an unlimited
supply of water. Think ofpotential evapotranspiration of "water
need". In other words, it would be the water needed forevaporation
and transpiration given the local environmental conditions. One of
the most importantfactors that determines water demand is solar
radiation. As energy input increases the demand forwater,
especially from plants increases. Regardless if there is, or isn't,
any water in the soil, a plant stilldemands water. If it doesn't
have access to water, the plant will likely wither and die.Soil
Moisture Storage (ST). Soil moisture storage refers to the amount
of water held in the soil at anyparticular time. The amount of
water in the soil depends on soil properties like soil texture and
organicmatter content. The maximum amount of water the soil can
hold is called the field capacity. Fine grainsoils have larger
field capacities than coarse grain (sandy) soils. Thus, more water
is available foractual evapotranspiration from fine soils than
coarse soils. The upper limit of soil moisture storage isthe field
capacity, the lower limit is 0 when the soil has dried out.Change
in Soil Moisture Storage (DST). The change in soil moisture storage
is the amount of waterthat is being added to or removed from what
is stored. The change in soil moisture storage fallsbetween 0 and
the field capacity.Deficit (D) A soil moisture deficit occurs when
the demand for water exceeds that which is actuallyavailable . In
other words, deficits occur when potential evapotranspiration
exceeds actualevapotranspiration (PE>AE). Recalling that PE is
water demand and AE is actual water use (whichdepends on how much
water is really available), if we demand more than we have
available we willexperience a deficit. But, deficits only occur
when the soil is completely dried out. That is, soilmoisture
storage (ST) must be 0. By knowing the amount of deficit, one can
determine how muchwater is needed from irrigation sources.Surplus
(S) Surplus water occurs when precipitation, P exceeds PE and the
soil is at its field capacity(saturated). That is, we have more
water than we actually need to use given the
environmentalconditions at a place. The surplus water cannot be
added to the soil because the soil is at its field
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capacity so it runs off the surface. Surplus runoff often ends
up in nearby streams causing streamdischarge to increase. Knowledge
of surplus runoff can help forecast potential flooding of
nearbystreams.
The Earth's Water BudgetWater covers 70% of the earth's surface,
but it is difficult to comprehend the total amount of waterwhen we
only see a small portion of it. The following diagram displays the
volumes of water containedon land, in oceans, and in the
atmosphere. Arrows indicate the annual exchange of water between
thesestorages.
Diagram adapted from: Peixoto and Kettani (1973)
The oceans contain 97.5% of the earth's water, land 2.4%, and
the atmosphere holds less than .001%,which may seem surprising
because water plays such an important role in weather. The
annualprecipitation for the earth is more than 30 times the
atmosphere's total capacity to hold water. This factindicates the
rapid recycling of water that must occur between the earth's
surface and the atmosphere.
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Computing a Soil - Moisture BudgetThe best way to understand how
the water balance works is to actually calculate a soil water
budgetusing the example below. To work through the budget, we'll
take each month (column) one at a time.It's important to work
column by column as we're assessing the moisture status in a given
month andone month's value may be determined by what happened in
the previous month.
J F M A M J J A S O N D Year
P 50 49 66 78 100 106 88 84 86 73 56 45 881
PE 0 0 5 40 84 123 145 126 85 44 8 0 531
P-PE 50 49 61 38 26 -17 -57 -42 1 29 48 45
DST 0 0 0 0 0 17 57 16 1 29 48 12
ST 90 90 90 90 90 73 16 0 1 30 78 90
AE 0 0 5 40 84 123 145 100 85 44 8 0 634
D 0 0 0 0 0 0 0 26 0 0 0 0 26
S 50 49 61 38 26 0 0 0 0 0 0 33 258
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Soil Moisture Recharge
Water BudgetField Capacity = 90 mm
J F M A M J J A S O N D Year
P 50 49 66 78 100 106 88 84 86 73 56 45 881
PE 0 0 5 40 84 123 145 126 85 44 8 0 531
P-PE 50 49 61 38 26 -17 -57 -42 1 29 48 45
DST 0 0 0 0 0 -17 -57 -16 1 29 48 12
ST 90 90 90 90 90 73 16 0 1 30 78 90
AE 0 0 5 40 84 123 145 100 85 44 8 0 634
D 0 0 0 0 0 0 0 26 0 0 0 0 26
S 50 49 61 38 26 0 0 0 0 0 0 33 258
Start the budget process at the end of the dry season when
precipitation begins to replenish the soilmoisture, called soil
moisture recharge, in September. At the beginning of the month the
soil isconsidered dry as the storage in August is equal to zero.
During September, 86 mm of water falls onthe surface as
precipitation. Potential evapotranspiration requires 85 mm.
Precipitation thereforesatisfies the need for water with one
millimeter of water left over (P-PE=1). The excess one millimeterof
water is put into storage (DST=1) bringing the amount in storage to
one millimeter (August ST =0so 0 plus the one millimeter in
September equals one millimeter). Actual evapotranspiration is
equal topotential evapotranspiration as September is a wet month
(P>PE). There is no deficit during this monthas the soil now has
some water in it and no surplus as it has not reached its water
holding capacity.During the month of October, precipitation far
exceeds potential evapotranspiration (P-PE=29). All ofthe excess
water is added to the existing soil moisture (ST (September) + 29
mm = 30 mm). Being awet month, AE is again equal to PE.Calculating
the budget for November is very similar to that of September and
October. The differencebetween P and PE is all allocated to storage
(ST now equal to 78 mm) and AE is equal to PE.Soil Moisture
Surplus
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18
During December, the study area is in winter and the potential
evapotranspiration has dropped to zeroas plants have gone into a
dormant period thus reducing their need for water and cold
temperaturesinhibit evaporation. Notice that P-PE is equal to 45
but not all is placed into storage. Why? At the endof November the
soil is within 12 mm of being at its field capacity. Therefore,
only 12 millimeters ofthe 45 available is put in the soil and the
remainder runs off as surplus (S=33).
Water BudgetField Capacity = 90 mm
J F M A M J J A S O N D Year
P 50 49 66 78 100 106 88 84 86 73 56 45 881
PE 0 0 5 40 84 123 145 126 85 44 8 0 531
P-PE 50 49 61 38 26 -17 -57 -42 1 29 48 45
DST 0 0 0 0 0 -17 -57 -16 1 29 48 12
ST 90 90 90 90 90 73 16 0 1 30 78 90
AE 0 0 5 40 84 123 145 100 85 44 8 0 634
D 0 0 0 0 0 0 0 26 0 0 0 0 26
S 50 49 61 38 26 0 0 0 0 0 0 33 258
Given that the soil has reached its field capacity in December,
any excess water that falls on the surfacewill likely generate
surplus runoff. According to the water budget table this is indeed
true. Note that inJanuary, P-PE is 50 mm and DST is 0 mm. What this
indicates is that we cannot change the amount instorage as the soil
is at its capacity to hold water. As a result the amount in storage
(ST) remains at 90mm. Being a wet month (P>PE) actual
evapotranspiration is equal to potential evapotranspiration.Note
that all excess water (P-PE) shows up as surplus (S=50 mm).Similar
conditions occur for the months of February, March, April, and May.
These are all wet monthsand the soil remains at its field capacity
so all excess water becomes surplus. Note too that the valuesof PE
are increasing through these months. This indicates that plants are
springing to life andtranspiring water. Evaporation is also
increasing as insolation and air temperatures are increasing.Notice
how the difference between precipitation and potential
evapotranspiration decreases throughthese months. As the demand on
water increases, precipitation is having a harder time satisfying
it. Asa result, there is a smaller amount of surplus water for the
month.Surplus runoff can increase stream discharge to the point
where flooding occurs. The flood durationperiod lasts from December
to May (6 months), with the most intense flooding is likely to
occur inMarch when surplus is the highest (61 mm).
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Soil Moisture Utilization
Water BudgetField Capacity = 90 mm
J F M A M J J A S O N D Year
P 50 49 66 78 100 106 88 84 86 73 56 45 881
PE 0 0 5 40 84 123 145 126 85 44 8 0 531
P-PE 50 49 61 38 26 -17 -57 -42 1 29 48 45
DST 0 0 0 0 0 -17 -57 -16 1 29 48 12
ST 90 90 90 90 90 73 16 0 1 30 78 90
AE 0 0 5 40 84 123 145 100 85 44 8 0 634
D 0 0 0 0 0 0 0 26 0 0 0 0 26
S 50 49 61 38 26 0 0 0 0 0 0 33 258
By the time June rolls around, temperatures have increased to
the point where evaporation isproceeding quite rapidly and plants
are requiring more water to keep them healthy. As
potentialevapotranspiration is approaching its maximum value during
these warmer months, precipitation isfalling off. During June P-PE
is -17 mm. What this means is precipitation no longer is able to
meet thedemands of potential evapotranspiration. In order to meet
their needs, plants must extract water that isstored in the soil
from the previous months. This is shown in the table by a value of
17 in the cell forDST (change in soil storage). Once the 17 m is
taken out of storage (ST) it reduces its value to 73.The month of
June is considered a dry month (P
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Soil Moisture Deficit
Water BudgetField Capacity = 90 mm
J F M A M J J A S O N D Year
P 50 49 66 78 100 106 88 84 86 73 56 45 881
PE 0 0 5 40 84 123 145 126 85 44 8 0 531
P-PE 50 49 61 38 26 -17 -57 -42 1 29 48 45
DST 0 0 0 0 0 -17 -57 -16 1 29 48 12
ST 90 90 90 90 90 73 16 0 1 30 78 90
AE 0 0 5 40 84 123 145 100 85 44 8 0 634
D 0 0 0 0 0 0 0 26 0 0 0 0 26
S 50 49 62 38 26 0 0 0 0 0 0 33 258
August, like June and July, is a dry month. Potential
evapotranspiration still exceeds precipitation andthe difference is
a -42 mm. Up until this month there has been enough water from
precipitation andwhat is in storage to meet the demands of
potential evapotranspiration. However, August begins withonly 16 mm
of water in storage (ST of July). Thus we'll only be able to
extract 16 mm of the 42 mm ofwater needed to meet the demands of
potential evapotranspiration So, of the 42 mm of water we wouldneed
(P-PE) to extract from the soil. In so doing, the amount in storage
(ST) falls to zero and the soil isdried out. What happens to the
remaining 26 mm of the original P-PE of 42? The unmet need for
watershows up as soil moisture deficit. In other words, we have not
been able to meet our need for waterfrom both precipitation and
what we can extract from storage. AE is therefore equal to 100 mm
(84mm of precipitation plus 16 mm of DST).
Conjunctive use of groundwater and surface waterThe principles
of hydrological cycle call for integration between surface and
groundwatermanagement. An aquifer undisturbed by pumping is in
approximate equilibrium and water is added bynatural recharge and
removed by natural discharge. In response to periods of abundant
precipitation,the water table levels rise and in time of drought,
the water level declines. When well is introduced in alocation
within the catchment, new conditions are created. Some water will
be removed from thestorage in the aquifer in response to reduced
head in the vicinity of the well and may induce increasedrecharge
from precipitation or from streams or it may decrease natural
discharge into streams orsprings. If discharge far exceeds the
recharge, the withdrawals will cause adjustments in the
wateraquifer to a point where significant volumes of water are
removed from storage over large portions of
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the aquifer. The consequences of such withdrawals include;
increased cost of pumping, for existingwells, harmful depletion of
stream flow, land subsidence, and intrusion of low quality
waters.The concept of safe yield is therefore used to express the
quantity of ground water that can bewithdrawn without impairing the
aquifer as a water source, causing contamination, or
creatingeconomic problems from increased pumping lift. Safe yield
will depend on the availability of water forrecharge,
transmissivity of the aquifer and in some cases; the safe yield is
limited by potentialcontamination.
If the rate of recharge of an aquifer is increased, the safe
yield is also increased, if an aquifer oflow transmissivity can be
recharged close to the point of withdrawal, the safe yield may also
beincreased. In addition, enhanced recharge may allow an aquifer to
function as storage reservoir.In addition to augmentation discharge
to surface stream flow especially during low flow seasons,there are
several advantages in storing water underground. The cost of
recharge may be lessthan the cost of construction of surface
reservoirs, the acqifer also serve as distribution systemand
eliminates the need of pipelines besides, water in surface
reservoirs is subject to evaporationand contamination, which is not
the case with groundwater storage. Hence optimal waterresources
management in a catchment nearly always involve conjunctive use of
surface andground water.
Artificial recharge may be used to enhance infiltration to
groundwater storage; either by means ofrecharge well or
infiltration field. In this case, surface water is diverted to
permeable groundwhere it infiltrates to the groundwater. In areas
where percolation rates are low or whererecharge route is via beds
of river channels, surface reservoirs may be used to store water
duringhigh flow when flow exceeds the percolation capacity of the
channel. This water is then releasedfor percolation when the
natural stream is low.
It clears therefore that conjunctive use of surface and
groundwater resources help to achievesustainable use of both ground
and surface water sources
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Watershed based planning
Hydrology is the science of water that is concerned with the
origin, circulation, distributionand properties of waters of the
earth and regional hydrology is the branch of hydrology whichdeals
with the effects of land management and vegetation on the quantity,
quality and timingof water yields - including floods, erosion and
sedimentation
Watershed, or catchment, is a topographic area that is drained
by a stream, that is, the totalland area above some point on a
stream or river that drains past that point. The watershed
orcatchment is often used as a planning or management unit.
River basin is a larger land area unit that, although comprised
of numerous sub watershedsand tributaries still drains the entire
basin past a single point. Land use, management andplanning is
often diverse and complex.
Watershed management is the process of guiding and organizing
land and other resourceuse on a watershed to provide desired goods
and services without affecting adversely soiland water
resources
Watershed management practices are those changes in land use,
vegetative cover, andother nonstructural and structural actions
that are taken on a watershed to achieve watershedmanagement
objectives. Integrated catchment management therefore is defined as
thecoordinated and sustainable use and management of land, water,
vegetation and othernatural resources on a water catchment basis so
as to balance resource utilisation andconservation.
Water as a resourceWater is the most important and most
absolutely necessary natural resource required byman. When human
demands for water are not met, there are problems . Extent of
worldwidewater supplies; over 97 percent of the water on earth (air
and land) is salty and therefore notavailable to meet our demands
Only 2.6 percent is fresh water of this, 77 percent is tied up
inglaciers and polar ice caps, 11 percent more is stored in deep
ground water and is generallynot available only 12 percent is left
for circulation. Most of this however, is locked up frommanagement
or manipulation in lakes, reservoirs, soil and groundwater storage.
Only 0.57percent enters into the hydrologic cycle within the
atmosphere and biosphere
The atmosphere is involved through the ET and precipitation
processes. The biosphereextends from the bottom of the rooting zone
to the top of the plant canopy. This is the portionof the water on
the earth's surface that can be affected by watershed
management,particularly the manipulation of the vegetation
How is this "usable" water distributed on a national basis or
catchment basis? Water Balance a process model based on monthly
values of temperature, precipitation and local soilmoisture storage
capacity is useful to answer this question.The hydrologic cycle can
be expressed as a continuity equation for any large or
smalllocation. It follows the conservation of mass law which simply
stated means that the water inthe hydrologic cycle is always
accountable
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The most common form of the so-called water balance equation
is:P - ET = Q
or, the amount of precipitation on any land mass minus the
amount of that water loss toevapotranspiration must provide the
watershed output, runoff Precipitation represents theequation (and
watershed) inflow and ET and Q represent the outflows
For any finite period of time, less than needed to establish the
long term average quantitativebalance above, the equation for any
area becomes:
P -(ET + Q) = + S
where the inflow and outflows don't balance and whatever the
difference, either plus or minusgoes into or comes out of storage
to make the continuity law work. This site of storagechange for a
watershed or river basin is the soil and bedrock aquifers. In any
location thequantities within the equation particularly the ratio
of P input to ET output to the atmospheredetermines how much, on an
average, is available for Q to meet our supply demands. Ofequal
importance is the distribution over time of both P and ET
does the precipitation come when the ET demands are high or low?
rainfall does not fall uniformly over time for any location
likewise, ET rates vary with time of day and season of the year the
time of the precipitation with respect to time of year and
temperature effects the
form of precipitation (snow?) which may in itself determine
whether it is immediatelyavailable for runoff
neither P nor ET are distributed uniformly spatially over the
watershed
Watershed based planning promotes decentralisation of planning
and management for thefollowing advantages;
Diversity between localities- demand for public services vary
from place to place bothin quantity and quality, decentralisation
can ensure efficient response to this variationin demand
Efficiency- Locally financed and provided services can be
produced at a lower costand enhance community participation as well
as voluntary organisation in such a wayas to reduce the costs
significantly
Accountability- Decentralised institutions are more accountable
to its constituents dueto proximity of the service providers to the
served people. The people also have abetter understanding of how
the institutions operate
Co-ordination- Since many local services are interdependent,
co-ordination of servicescan results to cost saving. Co-ordination
is much easier to attain in a decentralisedsystem