Environmental Impact Assessment Report - World … Impact Assessment Report Ndarugu Water Scheme...

Environmental Impact Assessment Report

Ndarugu Water Scheme

Water and Sanitation Services Improvement Project (WASSIP)

February 2009

Environmental Impact Assessment for Ndarugu Water Scheme i

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ACKNOWLEDGEMENT

Experts involved in the assessment would like to acknowledge all stakeholders who

participated in the assessment and compilation of the report. Special thank goes to

managing director GASWASCO Eng. Esther W. Njuguna, Technical Manager

GSWASCO Mr. Simon K. Ngugi, Gatundu South District Water Officer Mr. Joseph

K. Gitau and entire local administration headed be chief for Ndarugu Location Mr.

Joseph Kiruthi Chege.

We would also wish to appreciate contribution made by residents of Githobokoni area

towards the report especially during public participation session

Environmental Impact Assessment for Ndarugu Water Scheme ii

TABLE OF CONTENTS

ACKNOWLEDGEMENT ............................................................................................. I

TABLE OF CONTENTS ............................................................................................. III

ACRONYMS................................................................................................................ V

EXECUTIVE SUMMARY......................................................................................... VII

1: INTRODUCTION .................................................................................................... 1

1.1.GENERAL INFORMATION................................................................................. 1

1.2 PROJECT BACKGROUND .................................................................................. 2

1.3 PROJECT JUSTIFICATION.................................................................................. 3

1.4. STUDY OBJECTIVES.......................................................................................... 3

1.5 ASSESSMENT SCOPE AND TERMS OF REFERENCE.................................... 3

1.6 METHODOLOGY ................................................................................................. 4

2: PROJECT DESCRIPTION ...................................................................................... 6

2.1 PROJECT DETAILS.............................................................................................. 6

2.2 PROJECT SCOPE .................................................................................................. 6

3: BASELINE ENVIRONENTAL CONDITIONS...................................................... 7

3.1 PHYSIOGRAPHY.................................................................................................. 7

3.2 SOILS AND GEOLOGY ................................................................................................ 7

3.3 CLIMATE............................................................................................................... 7

3.4 HYDROLOGY ....................................................................................................... 7

3.5 BIOLOGICAL ENVIRONMENT.......................................................................... 8

4: POLICY AND LEGAL FRAMEWORK ................................................................. 9

4.1 GENERAL OVERVIEW........................................................................................ 9

4.2 NATIONAL POLICY ON WATER RESOURCES MGT & DEVELOPMENT.. 9

4.3 ENVIRONMENTAL MANAGEMENT AND COORDINATION ACT, 1999.. 11

Environmental Impact Assessment for Ndarugu Water Scheme iii

4.4 WATER ACT, 2002 ............................................................................................. 11

4.5 ENVIRONMENTAL GUIDELINES 2002 .......................................................... 13

4.6 PUBLIC HEALTH ACT ...................................................................................... 13

4.7 FOREST ACT 2002 .............................................................................................. 14

5: ENVIRONMENTAL IMPACT ASSESSMENT ................................................... 16

5.2 POTENTIAL NEGATIVE IMPACTS DURING OPERATION......................... 18

6: ENVIRONMENTAL MANAGEMENT PLAN .................................................... 19

6.1 CONSTRUCTION PHASE: ENVIRONMENTAL MANAGEMENT PLAN.... 19

6.1.1 CONSTRUCTION PHASE: ENVIRONMENTAL MANAGEMENT PLAN.. 20

6.3 OPERATIONAL PHASE: ENVIRONMENTAL MANAGEMENT PLAN...... 23

6.3.1 OPERATIONAL PHASE: ENVIRONMENTAL MANAGEMENT PLAN............................. 24

6.4 Decommissioning Environmental Management Plan……………………………27

7: CONCLUSION AND RECOMMENDATIONS ................................................... 28

LIST OF REFERENCES................................................................................................ 29

PHOTOGRAPHS.......................................................................................................... 30

Environmental Impact Assessment for Ndarugu Water Scheme iv

ANNEXES

ANNEX 1: MAP OF THE PROJECT LOCATION

ANNEX 2: WATER ANALYSIS REPORTS

ANNEX 3: STAKEHOLDERS PARTICIPATION

Environmental Impact Assessment for Ndarugu Water Scheme v

ACRONYMS

AWSB ATHI WATER SERVICES BOARD

CBOs COMMUNITY BASED ORGANIZATIONS

CEMP CONSTRUCTION ENVIRONMENTAL MANAGEMENT PLAN

DEMP DECCOMMISSIONING ENVIRONMENTAL MANAGEMENT

PLAN

DWO DISTRICT WATER OFFICER

EA ENVIRONMENTAL AUDIT

EIA ENVIRONMENTAL IMPACT ASSESSMENT

ERR ECONOMIC RATE OF RETURN

EMP ENVIRONMENTAL MANAGEMENT PLAN

GOK GOVERNMENT OF KENYA

IDA INTERNATIONAL DEVELOPMENT AGENCY

KFS KENYA FOREST SERVICE

KWS KENYA WILDLIFE SERVICE

NEAP NATIONAL ENVIRONMENT ACTION PLAN

NEC NATIONAL ENVIRONMENT COUNCIL

NEMA NATIONAL ENVIRONMENT MANAGEMENT AUTHORITY

NWSIRP NAIROBI WATER AND SEWARAGE INSTITUTIONAL

RESTRUCTURING PROJECT

UFW UNCOUNTED FOR WATER

OEMP OPERATION ENVIRONMENTAL MANAGEMENT PLAN

WHO WORLD HEALTH ORGANISATION

WaSSIP WATER SUPPLY AND SANITARY IMPROVEMENT

PROGRAM

WB WORLD BANK

WSRB WATER SERVICES REGULATORY BOARD

WRMA WATER RESOURCE MANAGEMENT AUTHORITY

WSP WATER SERVICE PROVIDER

WSTF WATER SERVICES TRUST FUND

Environmental Impact Assessment for Ndarugu Water Scheme vi

EXECUTIVE SUMMARY

Environmental challenges that Country faces today have serious implications on

water resources in Kenya. The challenges range from soil erosion, land degradation,

water pollution, water borne diseases and drying up of water catchments. Other water

supply related challenges include poor maintenance of infrastructure, over abstraction

which leads to conflicts over water resources among others.

The present Water and Sanitation Services in Nairobi and adjacent towns is under

extreme pressure due to the high population increase, development and growth over

the last three decades. Development has not matched with population growth. Water

and Sanitation problems are at times compounded by deliberate interference with the

existing infrastructure such as illegal tapping of water mains, blockage of sewers to

divert raw sewage into farms where sewage farming is practiced, dumping of solid

waste into drains, sewers, among others. The current deficiencies in the Water and

Sanitation Services affect the well being and living standards of a large population

residing within the City and its environs.

Another key challenge has been securing funding for capital investment in

infrastructure expansion and maintenance. The government of Kenya has applied for

and received credit from the International Development Association toward the cost of

Water and Sanitation Service Improvement Project (WaSSIP) that aims at

strengthening the institutional framework for water and sanitation services in Nairobi

and neighboring districts. Among priority projects for rehabilitation is Ndarugu water

supply scheme.

Ndarugu Water Scheme is located in Gatundu district, Ndarugu location and was

constructed in early eighties to solve water problems of residents of the larger

Gatundu district. The scheme gets its water from a small weir constructed a cross

Ndarugu River. Originally, the water was treated before supply to consumers. This is

no longer the case today. The treatment plant ceased operations due to high operating

costs (generator driven) coupled with low funding for operation and maintenance.

Nonetheless, the intake weir is still operational and supplies raw water to low altitude

Environmental Impact Assessment for Ndarugu Water Scheme vii

residents of Ndarugu. Scope of Ndarugu Water project comprises of construction of

Floculation tanks, Sedimentation basins and Filter units including associated works.

The main objective of the assessment was to identify potential impacts anticipated

from the development of the Scheme on the environment and social aspect with a

view of recommending appropriate mitigation measures for any anticipated adverse

impacts. The assessment was guided by EMCA 1999 as well as the EIA regulations

as outlined in the gazette Notice No. 56 of 13th June 2003.

The report identified key negative impacts of the project on environment to be land

degradation of the project site, air and noise pollution during construction and

operation, sludge generation and increased chemical usage mainly aluminum sulphate

and chlorine during plant operation.

From the assessment it was concluded that all significant negative impacts attributed

to the proposed water treatment plant can be mitigated. The benefits of the project far

outweigh any negative impacts, as a matter of fact the development is just an

improvement of the existing project so as to improve quality of livelihood.

Environmental Impact Assessment for Ndarugu Water Scheme viii

1: INTRODUCTION

1.1. General Information

The present Water and Sanitation Services in Nairobi and adjacent towns is under

extreme pressure due to the population increase, development and growth over the

last three decades. Development of water and sanitation facilities has not matched

with population growth. Water and Sanitation problems are at times compounded by

deliberate interference with the existing infrastructure such as illegal tapping of water

mains, blockage of sewers to divert raw sewage into farms where sewage farming is

practiced, dumping of solid waste into drains, sewers, among others. The current

deficiencies in the Water and Sanitation Services affect the well being and living

standards of a large population residing within the City and its environs.

To address part of the above challenges, the government of Kenya has applied for and

received credit from the International Development Association towards the cost of

Water and Sanitation Service Improvement Project (WaSSIP) that aims at

strengthening the institutional framework for water and sanitation services in Nairobi

and its neighboring districts. The project aims at supporting the water sector reform

effort by Improving reliability to water and sanitation services, provision of

affordable and sustainable water supply and sanitation services improvement,

Institutional strengthening and capacity building of water service providers, within

the AWSB area of jurisdiction.

It is estimated that the City of Nairobi and its adjacent towns have a water demand

short fall of about 70,000 cubic meters per day. This forces a large proportion of its

population to seek for other water sources whose quality and safety cannot be

guaranteed. These sources can be potential sources for water borne diseases.

Currently, AWSB has embarked on construction and rehabilitation of new water

treatment plants in order to improve water service delivery in Nairobi and selected

Environmental Impact Assessment for Ndarugu Water Scheme 1

small towns in the outlying districts. Among priority projects is rehabilitation is

Ndarugu water supply scheme.

Currently, Ndarugu water scheme supplies untreated water to its consumers after the

treatment plant became expensive to run. The residents then got connected to the

water transmissions mains from Ngethu to Nairobi city thus reducing the amount of

water reaching the city. It is hoped that upon commissioning of Ndarugu water

treatment plant and disconnecting current consumers of from the Nairobi mains, an

additional 4,000 cubic meters per day of water will be conveyed to Nairobi. This will

reduce the current water demand deficit in Nairobi city.

1.2 Project Background

Ndarugu water scheme is a raw gravity scheme that dates back to mid seventies. The

scheme comprises of 14 Km 2 No. 200mm diameter gravity mains with a production

of 4800 cubic meters per day. The source of Water is Ndurugu River which is a

perennial source with its sources in the Aberdare forest. With the encroachment of the

population to the areas around the source works, contamination of the water by

disease causing pathogens has been reported according to the recent water sampling

analysis conducted by the central water testing laboratories (see annex)

Moreover, during rainy season, the level of suspended solids goes beyond the WHO

standard for safe drinking water. Under the current reforms AWSB contracted Water

Service Providers that are required to comply with the terms and conditions of

Services Provision agreements which include providing safe water among other

targets. Provision of raw river water to consumers by water service providers in the

face of increased settlement along the river is not to be tolerated.

Rapid population increase has put pressure on current water supply resulting to

demand exceeding supply. More people are now demanding to be connected to the


Nairobi transmission mains while others are resorting to alternative sources whose

safety cannot be guaranteed.

1.3 Project Justification

With a design capacity of 4000 cubic meter per day the production will be sufficient

to meet the current water needs of residents of Ndarugu location. Development of the

facility will therefore guarantee safe and reliable water supply to the community

while at the same time release more water to the city of Nairobi thus reducing the

current water deficit. Other benefits will include reduced waterborne diseases,

reduced conflict of water between the two water service providers namely Nairobi

Water Company and Gatundu South Water and Sewerage Company.

1.4. Study Objectives

Main objectives of the assessment were to: • To identify potential impacts of the project to environment

• To generate baseline facts for monitoring and evaluation of the project.

• To recommend mitigation measures for negative impacts identified

• To present results of the EIA in a report form that can guide informed

decision-making about the project by stakeholders.

1.5 Assessment Scope and Terms of Reference

The Terms of Reference focused on environmental issues under the following scope:

• Impacts on flora and fauna by the project

• Socio- Economic implications

• The relationship of the project to existing policies, legislation and institutional

framework

• Proposed mitigation measures


• Proposed Environmental Management Plan which specifies responsibilities

for implementing mitigation measures, costs involved, time schedules and

actors.

• Identification of sources of baseline information and information gaps.

1.6 Methodology

The following tools/methods were used to conduct this EIA

• Review of Literature

• Filed visits and observation.

• Checklists.

• Structured Interviews/questionnaires

• Photographs.

Areas of focus included natural environment, human environment and physical

environment with emphasis on sustainability, environmental monitoring and

protection. Activities included the following:

• Gathering background information about the Water facility

• Preliminary visit to the site

• Review of the legal framework

• Definition of the objectives and scope of the assessment

• Preparation of assessment questionnaires

• Understanding the environmental conditions through interviewing people

who are likely to be affected by development

• Gathering of information on environmental conditions through observation,

photography and questionnaire administration.

• An assessment of strengths potential heath risks of the project and strategizing

for possible mitigation measures.

• Gathering of impact evidence, assessment, documentation, verification, site

inspection.

• Evaluation of impact evidence, compliance, exceptions, environmental

program status.


• Preparation of draft report to document findings and prepare

recommendations.


2: PROJECT DESCRIPTION

2.1 Project Details

The project is located in Gatundu South district, Gatundu division, Ndarugu location

General information on the current situation of the project is a follows:

Water source Ndarugu River Production 4800m3/day Registered consumers 3131 Active Consumers

1529

Trunk mains pipelines

14km – 2No 8” gravity mains

Estimated population served

68,000

Average revenue collections/month

340,000/month

Metered connections

768

Un-metered connections

774

Coverage area (designed)

116km2

2.2 Project Scope

Key investment proposed for implementation under this project is construction of

4000 cubic meters per day treatment plants comprising the following components:

• Construction of 2 flocculation tanks

• Construction of 2 units of sedimentation basins

• Construction of 2 filter units

Miscellaneous works include connection to the existing clear water tank, backwash

tank and operators building. Project cost for the constructions is estimated at Ksh.

45,000,000.


3: BASELINE ENVIRONENTAL CONDITIONS

3.1 Physiography

The project area is dominated by deep valleys and most areas have natural springs,

Ndarugu Water Treatment Works is in an area with major physiographic regions,

dominated by deeply incised V-shaped valleys with slopes greater than 30%, thus

highly susceptible to soil erosion. This zone covers the reservoir’s catchments area,

the forest reserve, Nyayo Tea Zone and influent river zones.

3.2 SOILS AND GEOLOGY

The terrain is made up of a series of tuffs and ash flows of varying thickness,

depending on the duration of the volcanic event. The weathering grade depends on

the time between volcanic events. Thus there is deposition of rocks consisting of

materials laid down as fall or flow deposits which grade upwards from agglomeratic

base through lapilli tuffs to fine grained tuffs. The major soils are histols around the

mountainous ranges and nitosols on the foot ridges to the Thika dam site. The

geology is associated with the volcanic activity of the Eastern African Rift Valley

3.3 Climate

The climate of the project area is cool and humid due to the influence of the

Aberdares mountain ranges. The air temperature ranges are 9.5 to 24 0C while the

water temperature range is 14 and 18 0C. Rainfall amounts vary from 1800 to 2100

mm increasing up towards the catchments. Rain is in two seasons with short rains

from October to December, and long rains from March to May.

3.4 HYDROLOGY

Drainage is dominated by three major rivers; Ndarugu, Thiririka, Ruabora and Thika

Rivers and some from the underground seepage. There are also numerous springs in

the area


3.5 Biological Environment

Most common tree species are the Prunus Africanas species, Croton megalocarpus,

pines, blue gums, wattles, and myriad of forest shrubs and aquatic macrophytes

especially Typha domingensis and Cypreus papyrus on the influence fringes. The

immediate catchment is covered by individual farmer small-scale tea plantations and

in some instances interspaced with blue gums and wattles with columns on Napier

grass making some of the bounders up the catchments.

Majority of the fauna species in the region are bird variety which include pelicans,

Egyptian geese, storks, crested cranes, weaverbirds, swallows and a variety of grebes

and coons (WSL Associates, 1996). The birds are distributed throughout the

reservoir but the highest densities are found in the influent river zones. The coons

and Egyptian geese are permanent residents but there are also visitors like fish eagles

whose number has increased after fish introductions there are domestic animals

including cows, goats, sheep and chicken.


4: POLICY AND LEGAL FRAMEWORK

4.1 General Overview

The government of Kenya has recognized the negative impacts on ecosystems

emanating from industrial, economic and social development projects that disregard

the environment. It is due to this that the country has put in place necessary

legislation that requires an EIA be carried out before implementation new project.

The Environmental Management and Coordination Act, 1999, directs that the

proponent of a project undertakes an EIA study and prepares a full EIA report for

presentation to the National Environmental Management Authority (NEMA) for the

necessary approval and issuance of a license. Besides, a number of other national

policies and legal statutes have been reviewed to enhance environmental

sustainability in national development projects across all sectors.

To facilitate this process, regulations on EIA and environmental audits have been

established under the Kenya Gazette Supplement No. 56 of 13th June 2003. Some of

the policy and legal provisions are briefly presented in the following sub-sections

4.2 National Policy on Water Resources Management and Development

The Sessional paper No. 1 of 1999 on the National Policy on Water Resources

Management and Development recognizes the effects of uneven distribution of water

in the country caused by diverse activities in the catchments. The effects include

reduction and deterioration of area under forest, siltation of water sources, increased

surface run-off, erratic water, water balance and groundwater recharge characteristics.

Following on this, therefore, the government undertakes to conserve water when and

where it occurs and regulate its utilization to benefit as many people and sectors as

possible

Construction of water projects (dams, irrigation schemes, flood control and water

transfer projects) have known negative effects on the environment and human life

including water logging, soil salinity, alkalization, social disruption, erosion and


siltation of water beds. Other effects are, encroachment into water river catchments

and flood plains, and demand for water from the installations. The policy

recommends a multi-objective approach and incorporations of comprehensive EIA

with all adverse impacts and mitigation measures clearly defined. Options for

reducing negative and enhancing positive effects need to be considered based on

careful analysis of environment to ensure all beneficiaries have access to water

without unduly polluting the environment

Sub-section 2.5.3 of the policy states “water development will be geared towards

improving the environment on which its sustenance depends and will not be expected

to adversely affect the quality of water resources in particular and the environment in

general. An Environmental Impact Assessment Report will, therefore, be made

mandatory for all major water development activities”.

While the National Policy on Water Resources Management and Development (1999)

enhances a systematic development of water facilities in all sectors for promotion of

the country’s socio-economic progress, it also recognizes the by-products of this

process as wastewater. It, therefore, calls for development of appropriate sanitation

systems to protect people’s health and water resources from institutional pollution.

Other development projects drawing water from a water supply should be

accompanied by corresponding waste management systems to handle wastewater and

other waste emanating there from. The same policy requires that such projects should

also undergo comprehensive EIA that will provide suitable measures to be taken to

ensure environmental resources and people’s health and safety in the immediate

neighborhood and further downstream are not negatively impacted by the emissions.

In addition, the policy provides for charging levies on wastewater on quantity and

quality (similar to polluter-pays-principle) in which those contaminating water are

required to meet the appropriate cost on remediation, though the necessary

mechanisms for the implementation of this principle have not been fully established

under the relevant Acts. However, the policy provides for establishment of standards

to protect the water bodies receiving waste water, a process that is ongoing.


.

4.3 Environmental Management and Coordination Act, 1999

Part II of the Environmental Management & Coordination Act, 1999 states that every

person in Kenya is entitled to a clean and healthy environment and has the duty to

safeguard and enhance the environment. In order to ensure this is achieved, part VI of

the Act directs that any proponent of a new project should undertake EIA study and

prepare an appropriate report for submission to the National Environmental

Management Authority (NEMA), who in turn may issue a license as appropriate. The

second schedule of the same Act lists water storage dams and river diversions among

the key waste disposal projects that must undergo EIA prior to implementation.

Sub-section 4 of Section 42 states that the National Environmental Management

Authority (NEMA) in consultation with relevant lead agencies shall issue guidelines

for the management of the environment of lakes and rivers and any contravention of

the regulations would constitute an offence.

Part VIII section 72 prohibits discharging or applying poisonous, toxic, noxious or

obstructing matter, radioactive or any other pollutants into aquatic environment.

Section 73 requires that operator of projects (including water supply and sewerage

systems) who discharge effluent or other pollutants to submit to NEMA accurate

information about the quantity and quality of the effluent.

4.4 Water Act, 2002

Section 3 of the Water Act states that all water resources are vested in the state,

subject to any rights of user granted by or under the Act, while section 5 vests the

right to use water from any resource to the minister unless alienated by or under the

Act.

The Act provides for the Water Resources Management Authority, whose

responsibilities shall be among others;


• Develop principles, guidelines and procedures for allocation of water resources,

• Receive and determine applications for parties for water use, as well as monitoring and enforcing conditions attached to the permit,

Regulate and protect water resources quality from adverse impacts as well as managing and protecting water catchments,

Gather and maintain information on water resource and from time to time publish forecasts, projections and information on water resources,

Liaise with other bodies for the better regulation and management of water resources. Section 18 provides for national monitoring and information systems on water

resources. Following on this, Sub-section 3 allows the Water Resources Management

Authority to demand from any person, specified information, documents, samples or

materials on water resources. Under these rules, specific records may be required to

be kept at the site and the information thereof furnished to the authority.

Section 25 provides for water permits on any use of water from a water resource,

while Section 27 stresses the need for any permit holder to construct works in

accordance to the conditions of the permit.

Issuance of the permit shall be done upon application, and among others shall be

subjected to an environmental impact assessment in accordance to EMCA 1999, and

any person opposed to the permit may object in writing. Section 70 gives a licensee

the duty to ensure that water services and associated works and facilities are provided,

maintained and progressively improved. Following on this, the licensee may enter

into an agreement under Section 71 with any party with respect to the maintenance of

the works as per the license for purposes of catchment protection, drainage of land,

soil conservation and control of vegetation or for wholistic of the purity and quantity,

of the water which for that time the license is authorized to take

Section 73 of the Act allows a person with a license to supply water (licensee) to

make regulations for purposes of protecting against degradation of sources of water

which he is authorized to take. Under the Act, the licensee could be a municipal

council or a private company or individual and the law will apply accordingly under

the supervision of the regulatory Board.


Section 75 and Sub-section 1 allows a licensee for water supply to construct and

maintain drains, sewers and other works for intercepting, treating or disposing of any

foul water arising or flowing upon land for preventing water belonging to the licensee

or which he is authorized to take for supply from being polluted. However, if the

proposed works will affect or is likely to affect any body of water in the catchments,

the licensee shall obtain consent from the authority.

4.5 Environmental Guidelines 2002

The EIA guidelines require that a project report be prepared in accordance with the

issues and general guidelines spelt out in the second and third schedules of the

regulations. These include coverage of the issues on schedule 2 (ecological, social,

landscape, land use and water considerations) and general guidelines on schedule 3

(impacts and their sources, project details, national legislation, mitigation measures, a

management plan and environmental auditing schedules and procedures.

The table below presents recommended guidelines for wastewater quality for

discharge into the public sewers and into open water bodies. The guidelines should be

particularly strict in this region since the receiving streams have seasonal variations

and the dilution capacity may be impaired. Further more the communities living

within the immediate neighbourhood and downstream rely on these streams for their

domestic water requirements.

4.6 Public Health Act

The Public Health Act (Cap 242) the main purpose of this Act is to secure and

maintain public health. Some of its provisions relevant to this project include

prohibition of nuisance activities such as spillage, discharge of untreated effluents or

noise or other condition deemed to be injurious or dangerous to human health.

Section 116 requires local Authorities to take all lawful, necessary and reasonably

practicable measures to maintain their jurisdiction clean and sanitary to prevent


occurrence of nuisance on conditional liable for injurious or dangerous to human

health.

The Act further states that nuisance conditions are defined according to the opinion of

Medical Officer of Health. Any noxious matter or waste water flowing or discharged

from any premises or project into a public street or into the gutter or site channel or

water course, irrigation channel not approved for discharge is also deemed as a

nuisance.

Part XI Section 129 of the Act states that it is the duty of every local authority to take

all lawful, necessary and reasonably practicable measures for preventing any

pollution dangerous to health of any supply of water which the public within its

districts has a right to use for drinking or domestic purposes. It’s also charged with

purification of water so polluted.

Part XII Section 136 states that all collections of water, sewage, rubbish refuse and

other fluids which permits or facilitate the breeding or multiplication of animals or

vegetable parasite of men or domestic animals or insects or other agents which are

known to carry parasite shall be deemed nuisance and are liable to be dealt with as

provided for in the Act.

4.7 FOREST ACT 2002

Part III section 18 of the forest Act requires Environmental Impact Assessment to be

conducted for any Proposed development in a forest reserve, Private forest or

sensitive forest area including watersheds to which this section applies, whether that

development is Proposed by, or is to be implemented by a person or organization in

the public or Private sector. Proponent of the development shall prepare and submit to

the Director of KFS an Environmental Impact Assessment of the proposed

development by a registered lead expert by NEMA.

Developments in forest land that need EIA include among others:


• Commercial Logging and forest industry and developments necessarily

connected with commercial logging and forest industry

• Mining developments

• Road construction or the laying of Pipelines

• Construction of dams, Power stations, electrical or telecommunication

installations.

• Such other like developments as may be prescribed.


5: ENVIRONMENTAL IMPACT ASSESSMENT

This chapter identifies and discusses giving magnitude of both positive and negative

impacts associated with the proposed project. Anticipated impacts are discussed

under three phases namely:

• Construction Phase

• Operational Phase

• Decommissioning Phase

Water Treatment Plant is a system of several processes; therefore it is likely to have

both negative and positive impacts on the environment as compared to raw water

transmission. Whereas the raw water supply may result to water borne related

diseases on the consumers, treatment plant will address the problem of water borne

diseases but will also result in increased use of chemicals and generation of sludge

into the environment.

5.1 Impacts during Construction

Impacts linked to this project are analyzed in the table below. They are categorized as

low, medium and high depending on their level of significance to the environment. It

is noted that all the anticipated negative impacts can readily be mitigated to minimize

their effects on the project environment while maximizing benefits of the proposed

development.


Table 4: Scoping Impacts during Construction

Environmental

Parameter

Significance

of impact

Contributory Factor

Water quality Low Water pollution due to accidental oil leakages

from plant and equipment into water natural

river course

Land degradation Low Disturbance of soil structure and loss of

vegetation at project site during excavations,

cutting, stockpiling.

Air quality Low Gaseous emissions from plant and also

particulate matter such as dust

Noise pollution Low Vibration and general noise from construction

machineries

Construction traffic Low Vehicular movement confined at project site.

Site far from main access roads

Loss of biodiversity Low Localized vegetation clearance at construction

sites leads to loss of biodiversity

Social interruptions/

Resettlement

N/A Construction is taking place on existing

government land without any settlements

Occupational health

and safety

Low Accidents normally associated with

construction works and equipment handling


5.2 Potential Negative Impacts during Operation

Main impacts of the treatment plant during operation phase are

5.2.1 Sludge generation and disposal

During operation of the treatment plant, the system will generate sludge that will

require being disposed in safe manner. The frequency of desludging and volume

of sludge generated will depend on the quality of the raw water in Ndarugu River.

This will also be a function of agricultural activities along and upstream of the

water intake location. Sludge is expected to be high during rain season when

water is turbid.

5.2.2 Chemical handling (Chlorine and Aluminum Sulphate)

In conventional water treatment plants, Aluminum sulphate is used to assist in

flocculation, coagulation and sedimentation processes. Part of it will end up in the

sludge. Chlorine is used to disinfect water and ensure bacteriological safety

during transmission of water to the consumer. Proper storage and handling

measures will need to be put in place to avoid accidents associated with mis-use

or poor handling/disposal of the same.

5.2.3 Backwash Water from Water Filters

It is normal for sand filters to clog after some time during operation of the water

treatment plant. Routine maintenance requires backwashing using treated water is

usually carried out. The backwash water may contain some chemicals used in the

water treatment process that will require to be pre-treated before releasing into

Natural River. Other impacts are less significant and can be easily mitigated.



6: ENVIRONMENTAL MANAGEMENT PLAN

The Environmental Management Plan stipulates actions and measures to be put in

place in order to mitigate impacts that the project is likely to cause to the

environment. The assessment report has been prepared to comply with the

requirements of the Environmental Management and Co-ordination Act 1999. EMP

presented in this chapter summarizes significant impacts identified and proposes

remedial measures for their remedy. The EMP has included various actors responsible

for executing the recommended actions, estimated cost for the action and measurable

indicators.

6.1 Construction Phase: Environmental Management Plan

A construction Environment Management Plan (CEMP) is a practical and achievable

plan of management to ensure that any environmental impacts during design,

planning and construction phase are minimized. The main issues during construction

are:

• Loss of fauna and flora

• Noise and vibrations

• Water pollution

• Air pollution

• Waste generation

• Soil contamination

6.1.1 CONSTRUCTION PHASE: ENVIRONMENTAL MANAGEMENT PLAN

Environmental Activity

Anticipated Impact Management and Mitigation Actors Cost (KSH)

Minimize vegetation clearance to construction site

Contractor

Landscaping and beautification of the project site after project completion with local flora and fauna

Contractor

Clearance of Loss of flora and Fauna vegetation

Practicing soil conservation measures at the site Contractor

50,000

All equipments used during construction be maintained of acceptable decibel levels. Provide workers with suitable gear

Contractor

Noise dampening materials to be used where excessive noise generating- equipments are in use and use of appropriate cushioning for heavy equipments

Contractor

Use of efficient mechanical plant and energy savers on site

Contractor

Ensure machinery are regularly serviced to avoid leakages and spillages

Contractor

Improvement on catchments arrangement and protection through re-afforestation program

Contractor

50,000

Excavation of foundations

Noise and vibrations

Proper handling of both liquid and solid waste. Contractor Dust/smoke/partic Impact on air quality Wet work areas, materials, heaps and mulch bare Contractor


grounds to minimize dust emissions Use of dust suppressants

Contractor

Maintain equipments and machinery to manufacturers specifications

Contractor

ulate generation by plant/traffic circulation

Provide appropriate personal protective equipments

Contractor

150,000

All wastes shall be contained on site prior to disposal using appropriate storage containers

Contractor

All waste shall be sorted at the source and disposed off in an approved manner.

Contractor

Recycle all wastes that can be recycled example plastic bags, cement bags and metallic wastes.

Contractor

Liquid and solid waste problem

Impact on water and soil quality

All wastes shall be regularly cleared from site and disposed of in approved manner

Contractor

200,000

Provision of appropriate induction training and regular updating of workers skill on occupational health and safety matters

Contractor

Provide appropriate personnel protective equipment (PPE) to workers and any visitors

Contractor

Provide for First Aid facilities as per the Factories and other Places of Work Act

Contractor

Develop and implement a detailed and site specific Emergency Response Plans.

Contractor

Site Activities Ill health by workers

Provide for appropriate signage and warnings at work sites

Contractor

75,000


Monitoring and Inspections

Negative impacts mitigated Regular monitoring of proposed measures to ensure compliance

AWSB/ GSWSCO 100,000

Subtotal 1 725,000



6.3 Operational Phase: Environmental Management Plan (OEMP)

An operation EMP focuses on sound environmental management practices that will be

undertaken to minimize adverse impacts on the environment throughout the economic life

of the facility. The EMP also captures measures that should be taken in event of an

emergency during the operation phase.

The OEMP has been developed to deal with the following problems

• Sludge generation and management

• Noise and vibrations

• Energy / fuel Consumption

• Occupational health, Safety and Environment

• Overall management strategy expenditure and project maintenance


6.3.1 OPERATIONAL PHASE: ENVIRONMENTAL MANAGEMENT PLAN

Environmental activity

Anticipated Impact Management and Mitigation Actors Cost (KSH)/Annum

Alternative 1 Dewater the sludge into pellets and apply quicklime treatment to dewatered sludge in order to create a pathogen and odour free product before disposal to a landfill.

GSWSCO

Alternative 2 (Recommended) Dry sludge in the drying beds which are normally concrete platforms filled with drainers for the leachates which are directed to the back wash channel

GSWSCO

Sludge generation Impact on water and soil quality

Disposes off in appropriate landfill or abandoned quarry site.

GSWSCO

Establish an oxidation lagoon to contain the backwash ater to allow stabilization and neutralization w

GSWSCO

Direct the stabilized and neutralized backwash water into a soak pit or controlled wetland.

GSWSCO

Back wash water

Increased siltation and chemical water into rivers

Recommended Recycle the stabilized backwash water back to the system to the filters

GSWSCO

180,000

Ensure machinery (pumps/motors) is regularly serviced to ensure high efficiency

GSWSCO AWSB

Heavy energy use Impact on energy resources

Use energy efficient /saving equipment or plant on sites GSWSCO

200,000

Chemical Handling

Contamination of water and soil quality Improve chemical handling, avoid leakages and

spillages


Appropriate record keeping of data on chemicals and material safety data sheets

Awareness creation amongst workers

70,000

All equipment used to be regularly maintained to ensure they operate efficiently

GSWSCO

Noise dampening materials used where excessive noise generating-equipment are in use

GSWSCO

Use of appropriate cushioning for pump set GSWSCO

Operating of plant Noise and Vibrations

Installation of noise and vibration monitoring systems and provide staff with appropriate gear

GSWSCO

50,000

Carryout a baseline survey of environmental issues and keep record on them through regular monitoring

AWSB GSWSCO

Environmental Monitoring

Effectiveness of measures

Schedule for revising and updating the EMP. This can be achieved through bi annual audit and implementation of recommendation of the environmental impact assessment

AWSB

100,000

Liaise with the Directorate of Occupational Health and Safety Department to provide for appropriate induction training and regular updating of worker skill on occupational health and safety matters

GSWSCO AWSB

Provide appropriate personnel protective equipment (PPE) to workers and any visitors

GSWSCO

Provide for First Aid facilities as per the Factories and other Places of Work Act

GSWSCO

Occupational Health and safety

Impact on workers health

Develop and implement a detailed and site specific GSWSCO

75,000

Emergency Response Plans. Provide for appropriate signage and warnings at work

sites

GSWSCO

Subtotal 2 515,000 Grand total 1,140,000


6.4 Decommissioning Environmental Management Plan

The economic life of a water treatment plant is at least 25 years. It is not practical to

estimate at the moment the cost implications of the decommissioning phase. It is

however, recommended that before decommissioning is executed, a comprehensive

decommissioning plan has to be developed by all the stakeholders. The decommissioning

action plan has to capture all the issues that need to be handled during the dismantling

exercise. The management has to notify responsible authorities in this case NEMA on the

intentions to decommission the facility within 1 year in order for the authority to carryout

assessment and determine potential negative impacts on environment and therefore

giving recommended mitigation measures.


7: CONCLUSION AND RECOMMENDATIONS

Ndarugu region is phasing critical drinking water quality challenge. Constructing

Ndarugu Water Treatment Plant will avail treated water to the community hence reducing

cases of water borne related diseases which are common in the region. Completion of the

treatment plant will also release about 4,000m3/day to Nairobi city. The latter is currently

being supplied to Ndarugu in the absence of any treated water for the inhabitants.

From the assessment it is concluded that all significant negative impacts attributed to the

proposed Water treatment Plant can be effectively mitigated. The benefits of the project

far outweigh any negative impacts. As a matter of fact, the development is just an

improvement of the existing project so as to improve quality of livelihoods.

Recommendations

The area is currently dominated with Eucalyptus trees stretch even into the river riparian.

It is recommended that the same should be replaced by indigenous trees of the Aberdare

forest. Trees are essential to minimize occurrence of landslides which are likely to occur

in Ndarugu area due the steep valleys.

Plans should be made to connect the plant to electricity mains supply as use of generator

will be costly not to mention the associated noise pollution.

Include design for the biological lagoon that will handle sludge and back wash water in

the overall design of the project.


LIST OF REFERENCES

1) Department of Environment, the World Bank, Washington DC. “Environmental Assessment Source Book, Volume I – Policies, Procedures and Cross – Sectral Issues” June 1998.

2) Environment Management and Coordination Act (EMCA) 1999.

3) Gerald k. Rukunga “Environmental Health for East Africa. African Medical and

Research Foundation” (AMREF). Nairobi, Kenya.

4) G.M. Wamukoya and F.D.P. Situma. “Environment Management in Kenya.” A Guide to the Environment Management and Coordination Act (EMCA) 1999”

5) Hussein Abaza, - DTIE-ETB, UNEP: Iron Biset-BTM Cordah Limited. Bastry

Sadler – UNEP Adviser, “Environmental Impact Assessmen t and Strategic Environmental Assessment: Towards an Intergrating Approach.

6) Kenya Institute of Administration, “Lecture and Tutorial Notes: Environmental

Impact Assessment and Environmental Audit Course No. 12/2004 from 16th – 26th November 2004”

7) Nairobi water and sewerage emergency physical investments project (NWSEPIP).

Global study completed in 2005 by the joint venture of M/S sorgreah consultants and Gape Consultants.

8) R.E. Munn, editor, Environmental Impact Assessment (EIA), Principles and

Procedures.” Published on behalf of the scientific committee on problems of the environment (SCOPE) of the International Council of Scientific Union (ICSU) by John Wiley & Sons. Chichester. New York. Brisbane. Toronto.

9) Republic of Kenya “Environmental Impact Assessment (EIA) Guidelines and Administrative Procedure.” National Environment Management Authority (NEMA)., Nairobi, Kenya, November 2004.

10) Republic of Kenya “community guide to environmental issues and EMCA,

1999 Western Province.” Environment law project: Environmental Liaison Center International (ELCI), Nairobi Kenya, March 2005.

11) Republic of Kenya “water and beyond: water beyond the taps.” Water service

boards Lake Victoria North. Newsletter issues No.2

12) Susan Dawson and Lemore Manderson, Tropical Health Program; University of Queensland Medical School, Herstone Road, Herstone, Brisbane Qid 4006 and Veronica L. Tallo, Research Institute of Tropical Medicine, Alabama, Mantilupa Metro Manila, Philippines. “A Manual for the Use of Focus Groups”.


PHOTOGRAPHS

Plate. Description Photographs Plate 1.

Weir and intake works to Ndarugu Water Treatment Plant.

Plate 2.

Plate showing flocculation and sedimentation tanks under repair.


Plate 3

Aerial view of the entire treatment plant.

Plate 4

One of the community bridges across Ndarugu River.


Plate 5

Existing

Plate 6

Water Resources Management Authority gauge for measuring volume of water in Ndarugu river


Annex 1: Map of Project Location


Annex 2: Water Quality Analysis Report


Environmental Impact Assessment Report - World … Impact Assessment Report Ndarugu Water Scheme...

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