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A-E Services for Monitoring and Milestone Verification of USAID-Funded Waran Canal and Gomal Zam Dam Command Area Development Project in Khyber Pakhtunkhwa
Gomal Zam Irrigation Project-Siltation Rapid Assessment Overview November 2017
IQC No AID-391-I-11-00002 Contract No AID-391-TO-16-00001
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Document history
A-E Services for Monitoring and Milestone Verification of USAID-funded Waran Canal and Gomal Zam Dam Command Area Development Project in Khyber Pakhtunkhwa.
Gomal Zam Irrigation Project-Siltation Rapid Assessment Overview Report
This document has been issued and amended as follows:
Version Date Description Prepared by Reviewed
by
Approved
by
01 November
07, 2017
Siltation Rapid
Assessment
Overview Report
AM, MMS, UT,
MZ,SRS, FMK,
MZM
FMK FMK
02 November
16, 2017
Revise to
comments
AM, MZM FMK FMK
AM Atif Murtaza
FMK Fazal Mahmood Khakwani
MMS Muhammad Munawar Saeed
MZ Mian Zia-uddin
MZM Muhammad Zubair Mughal
SRS Saif-ur-Rehman Sherani
UT Umer Tariq
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Contents
1 Executive Summary 1
2 Background 3
2.1 Objective of Study 4 2.2 Methodology Adopted 4 2.3 Site Visit reference 5 2.4 Visit Locations 5 2.5 Schedule of Site Visit 5
3 Sources of Siltation 7
3.1 Outflows from Gomal Zam Dam 7 3.2 40km Stretch of Gomal River 7 3.3 River Course 8
4 Causes of Siltation in Canal System 9
4.1 Location of Diversion Weir 10 4.2 Barrage Gate Operation 10 4.3 Local Irrigation Practices 11 4.4 Local Siltation due to Blockage in the distribution system 11 4.5 Delayed Construction of Waran Canal & Watercourses 12 4.6 Canal Operation Staff of GZID 12 4.7 Annual Cleaning and Maintenance of Canal System 13
5 Recommendations for Silt Control in Gomal Zam 14
5.1 Short-Term Measures 14
5.1.1 Proper Operation of Barrage Gates 14
5.1.2 Taking Over of the Entire GZIP by Provincial Irrigation Department 15
5.1.3 Removal of Obstructions in Canal System 15
5.1.4 Social Awareness of Farmers / Locals 16
5.1.5 Maintenance of Canal Berms 16
5.1.6 Routine Canal Cleaning 16
5.1.7 Completion of Waran Canal & Watercourses 16
5.2 Long-Term Measures 16
5.2.1 Provision of Silt Ejector 17
5.2.2 Watershed management for 40km stretch 17
5.2.3 Construction of Check Dams 17
6 Conclusion 1
7 Limitations of the Study 1
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Appendices
Appendix A: Minutes of Meeting with Stakeholders
Appendix B: Visit Photographs
Appendix C: Documents received and reviewed
Appendix D: River Discharge, Sediment, Water Quality record
Appendix E: Measured Canal Discharges
Appendix F: Data Received from GZID
Appendix G: Suggested Improvement at Barrage Location
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List of Abbreviations
A-E Architect - Engineer
COR Contracting Officer’s Representative
D I Khan Dera Ismail Khan
EDF Environmental Document Form
EMMP Environmental Mitigation and Monitoring Plan
FDT Field Density Test
FWO Frontier Works Organization
GZIP Gomal Zam Irrigation Project
GZID Gomal Zam Irrigation Division
HPK Halcrow Pakistan
HSE Health, Safety and Environment
HSEM Health, Safety and Environment Management
KDC Kundi Development Corporation
KP Khyber Pakhtunkhwa
MC Management Consultant
MSDS Material Safety Data Sheet
NOC No Objection Certificate
PCC Plain Cement Concrete
PID Provincial Irrigation Department
PIL Project Implementation Letter
PPE Personal Protective Equipment
QA Quality Assurance
RD Reduced Distance
SBC Shah Baba & Co
SC Sarwar Construction Pvt Ltd
SKC Shouqat Khan Contractor
USAID United States Agency for International Development
VRB Village Road Bridge
WAPDA Water and Power Development Authority
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1 Executive Summary
This Siltation Rapid Assessment Overview Report of Gomal Zam Irrigation Project
(GZIP) presents a rapid assessment on the siltation problem and is based on the
coordination meetings with stakeholders, site visit of the dam, watershed, barrage
and silted up irrigation canals and review of the available project documents.
During site visit it was observed that in addition to the controlled water release
from Gomal Zam Dam, the 40km stretch of the Gomal River is also being fed by a
number of un-controlled hill torrents on its way with contribution from three main
nullahs / streams namely Sherana, Neeli Kuch & Spin Kuch during the rainy
season.
It is evident from the findings of the site visit that mainly the silt deposition in the
system is from the 40km long stretch of the Gomal River (between dam and
barrage). The silt transported by Gomal River 40km reach accumulates at the
upstream of diversion weir and enters the canal system due to improper use of
barrage / diversion weir gates. It is eminent to mention that water flow from
Gomal Zam Dam is not contributing any silt in the Gomal River as clear water
discharges from the dam lower outlet.
The accumulated silt at diversion weir enters the main canal and further to
distribution system. The control of barrage gates have been affected by break-
down of the available electric power generator and less staff for barrage gates
operation duing flood event.
The deposition of silt in the distribution canals is mainly due to illegal blockages
by local farmers by filling the canal section with stones, bushes , trolley load of
clay and similar which results in velocity reduction of canal flow and
consequently silt deposition occurs. Adittional factors contributing silt deposition
in canal system include ; delayed handing over of system to Provincial Irrigation
Department, non-allocation of maintenance budget by the Provincial Irrigation
Department, dealyed social mobilization of the beneficiaries on new canal system
and delayed construction of Waran Canal and of watercourses.
A number of remedial measures have been suggested which includes short term
measures and long-term measures;
The short term measures include proper control of barrage gates in order to
control silt entry into the main canal. The gate operation will be improved by
development of Gate Operation Manual by WAPDA, training of gate operating
staff, provision of power generator with fuel availability all times. In addition,
extension of upstream concrete floor of the canal head regulator approach channel
has been suggested to restrict the bed load entrance in the canal approach channel.
Currently, it appears difficult to flush silt once entered into the canal head
regulator approach channel with the operation of under sluice gates in the
presence of a divide wall. The other short term measures include social awareness
of farmers / locals to get familiarization about new canal system, annual canal
cleaning, maintenance of canal berms to control vegetation growth, removal of
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obstructions in canal system and early completion of Waran Canal & of
watercourses.
The long term measures include the provision of Silt Ejector across the canal about
300-400m downstream of canal head regulator, watershed management for 40km
stretch by plantation to control silt erosion from existing nullahs and construction
of check dams to control transportation of silt to diversion weir. The long term
measures requires extensive study and environmental impact assessment before
making any decision.
Based on the site observations and detailed discussion with stakeholders it is
expected that implementation of short term measures will improve the situation
regarding siltation issue in canal system. Further it is suggested that the
completion of Waran Canal & watercourses and handing over of complete system
to Provincial Irrigation Department must be expedited. Once the system is fully
operational and routine maintenance undertaken, the silt situation in the canal
system may be re-assessed and decision to be made accordingly regarding long
term measures.
This report is limited to overview of siltation issue in Gomal Zam Dam canal
system as required by USAID. The sources of siltation, causes and remedial
measures have been discussed in respective chapters. Due to prevailing security
situation our assessment is limited to our observations during the short site visit,
on discussions with the stakeholders and on the review of shared project
documents. Detailed assessment will be required for decision regarding long term
measures, if needed to consider.
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2 Background
Halcrow Pakistan (HPK) is providing Architectural and Engineering Design
Services to USAID for the Task Order “Monitoring and Milestone Verification of
Waran Canal and Gomal Zam Dam Command Area Development Project in
Khyber Pakhtunkhwa”. Gomal Zam Dam together with its irrigation canals
network system was completed with USAID assistance in 2015‐16.
Gomal Zam Irrigation Project diversion weir (barrage) is located at Kot Murtaza,
nearly 40km downstream of Gomal Zam Dam site. The objective of GZIP was that
upon completion, the canal will ensure efficient conveyance and distribution of
Gomal Zam Dam water into the command area through a network of Gomal Zam
Irrigation canals. GZIP will provide reliable irrigation water to about 77,321ha of
command area scattered over three Tehsils; Tank, Kulachi and DI Khan through a
network of distributaries, minors and on farm watercourses.
GZIP Diversion weir (barrage) and the 17 distributaries are almost completed with
remaining one distributary (Waran Canal with its minors) and few minors of GZIP
are still under implementation phase. WAPDA has implemented the project and
has handed over 7 flood area distributaries and the diversion weir (barrage) to
Provincial Irrigation Department (PID) in October 2016. While, discussion is still
on-going between WAPDA, FWO (Implementation Contractor) and PID on the
taking over of the remaining distributaries.
The extension services activities for Gomal Zam Command Area Development are
being implemented through Provincial Agriculture and Livestock Corporation by
Provincial Planning and Development Department. The activities are in initial
stages of implementation.
Usually, siltation occurs in all the newly constructed system as the system is
undergoing a readjustment phase including regime disturbance in the main river
as a result of man-made construction, understanding and acceptance of new
system by the beneficiaries and similar.
Currently, the canal system is passing through initial adjustment phase as it has
started operation from 2014 onward. In this phase, the system is facing operational
problems in the form of ownership, improper maintenance, lack of periodic
annual cleaning system, illegal interference of farmers to divert canal flow at their
own will and interest and similar.
Under these prevailing conditions, complaints from the farmers and officials of
Irrigation Department were raised that some canals under the GZIP are frequently
silted up which not only incur costs of de-silting and cleaning to the farmers on
the one hand but also reduce canal water flow capacity. Thus, depriving tail‐end
farmers of their due water share and equity. In order to have an update on the silt
deposition in irrigation canals under GZIP, USAID has advised HPK to analyse
the situation and provide a Rapid Assessment Report in this regard.
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2.1 Objective of Study
The objective of the study was to conduct a Rapid Assessment of Siltation of
Gomal Zam Irrigation Project to capture ground realities and to recommend
possible mitigation measures for minimizing the effects of siltation of the GZIP
system. The siltation assessment overview has covered the following aspects;
To update on the situation of silt deposition in diversion weir (barrage), main
canal, distribution canals and watercourses.
Source of siltation (e.g. water released from dam or 40km strip downstream
the dam to barrage or direct silts from mountains into canal system or back-
filled soil drop into canals or any combination of these sources);
Causes of siltation at diversion weir and canal system
Impacts of siltation on water flows and distribution;
Any other observation regarding siltation; and,
Recommendations for control of silts in barrage, main and distribution canal
system and sedimentation of reservoir based upon cost-benefit analysis.
2.2 Methodology Adopted
The study was carried out for rapid assessment of the silt situation, its causes and
impacts. Methodology for the study includes;
(i) Discussions with concerned officers of WAPDA, Management Consultant,
FWO and Gomal Zam Irrigation Division (GZID). Meeting minutes are
attached as Appendix-A
(ii) Site observation of the dam, river and canal distribution system. Visit
photographs are attached as Appendix-B.
(iii) Interviews with relevant farmers of the command area; and,
(iv) GZIP documents review. List is attached as Appendix-C.
Documents reviewed included, Report on GZD Feasibility study, 1995, Project PC-
I, Detailed Project Report Design of Diversion Barrage of Gomal Zam Dam
Irrigation Component, GZDP River discharge, Sediment, Water quality and
Climatological Data Report for the year 2014, 2015 and 2016, GZDP-02 Irrigation
Component Operation and Maintenance Manual of Canal and Gated Equipment,
Comprehensive Model of Diversion Barrage Below Gomal Zam Dam (Hydraulic
Model Study) IRII&PD GO Punjab.
Discussions on siltation, its causes, and frequency of occurrence, impact and
remedial measures were held in a joint meeting with concerned staff of WAPDA,
FWO/AREAA (the designer), Management Consultant and Gomal Zam Irrigation
Division (GZID) on September 19, 2017. Further a separate meeting was conducted
with the GZID staff on siltation problem.
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Observation and assessment of water flows from dam to diversion weir, barrage,
canal and its distribution system was carried out from September 25-27, 2017.
Interviews with framers: Interviews and group discussions were conducted with
selected Water Users Associations (WUA) on September 20, 22 and 23, 2017 and
with farmers available on site during field assessment visits on September 26-27,
2017.
2.3 Site Visit reference
The visit was carried out with reference to the email instruction from the USAID
Contracting Officer’s Representative (COR) dated August 30, 2017.
2.4 Visit Locations
Following sites were visited to conduct the rapid assessment of siltation in GZIP;
(i) Dam site;
(ii) 40km long stretch of the Gomal River starting from the Dam up to the Site
of Diversion Weir (travelling along the road by vehicle);
(iii) Diversion weir (barrage) site; and,
(iv) Identified silt affected GZIP canals and distributaries by GZID.
2.5 Schedule of Site Visit
Following was the schedule of meetings and of site visits;
(i) September 19, 2017; Meeting with WAPDA, Management Consultant,
FWO/AREAA (The Designer) and Gomal Zam Irrigation Division about
siltation problem of GZIP channels;
(ii) September 20, 2017; Separate meeting conducted with Provincial Gomal
Zam Irrigation Division and Rudkohi Irrigation System staff on siltation
problem;
(iii) September 22, 2017; Site visit of DI-6 Head Regulator and along the
distributary to observe and assess the obstructions made by beneficiary
farmers in the distributary for diverting water and also meeting with the
concerned farmers to understand their problems related to irrigation water
requirement.
(iv) September 23, 2017; Site visit of Disty-7, Disty-10, Disty-11, Disty-12 and
Disty-13 head works together with meeting the farmers / community to
understand flow diversion problem.
(v) September 25, 2017; Site visit to Gomal Zam Dam site, 40km long stretch of
the Gomal River downstream of the dam up to the GZIP diversion weir
(barrage) location at Kot Murtaza;
(vi) September 26, 2017; Ste visit of GZIP main canals and distributaries;
Makaliwah, Khanwand, Distributary-RB, Distributary-R1, Distributary-1,
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Distributary-2 and Distributary-3 its head regulators and meeting with
respective beneficiaries to understand their views regarding frequent silt
deposition in irrigation channels under GZIP. Drive along Disty-3 with
community to understand the shared problem of canal blockage by
influential farmers depriving the downstream beneficiaries of their due
share of water;
(vii) September 27, 2017; Site visit to Disty-4, Disty-5, Disty-8 , Disty-9, Disty-10
and Disty-11, their head regulators and meeting with the community to
understand their point of view related to existing situation of irrigation
water in canals and their current practise of water diversion from canals.
(viii) September 28, 2017; Travel back to Islamabad from DI Khan.
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3 Sources of Siltation
From the findings of the site visit it was evident that the primary source of silt
deposition in the system is from the 40km long stretch of the Gomal River
downstream of the Gomal Zam Dam up to the diversion weir (barrage) site. Major
contributor of silt generation in this 40km reach are its tributaries / nullas (hill
streams) which brings eroded materials in the hill torrents during flash floods into
the Gomal River which in turn carry it downstream towards barrage which finally
enter the canal system. During rains muddy water loaded with heavy silt from the
existing big and small nullahs waterways enters the Gomal River at various
locations and discharge its flow in the 40km long stretch of the Gomal River. It
was noted during site visit that water flow from Gomal Zam Dam itself is not
contributing any silt in the Gomal River as clear water discharges from the dam
lower outlet. Our observation regarding possible sources of siltation in the system
are as under:
3.1 Outflows from Gomal Zam Dam
The dam site was visited to observe the silt situation in the discharging water from
the dam. The reservoir of dam, as observed, was of clean water. It is a natural
process that when a river is ponded behind a dam, the sediments settles at the
bottom of the reservoir. The velocity of entering water from the catchment area on
approaching the reservoir reduces too much and resultantly water spreads in the
large storage area, any silt traveling from the catchment area settles down and
deposit at the bottom of the dam. Consequently clean water discharge was
observed at the outlet point of the dam into the Gomal River. However, these silts
are not carried down to the canal system as they are trapped inside the reservoir at
the upstream of the dam structure.
3.2 40km Stretch of Gomal River
The 40km long stretch of the Gomal River from Gomal Zam Dam up to the
diversion weir (barrage) of the canal system was noted as the primary source of
siltation for the GZIP system. The silt accumulated in 40km reach of Gomal River
travels up to the diversion weir and then enters the canal system. There are a
number of nullahs/ kuchs discharging into the 40km long part of the Gomal River at
different locations.
The main contributing nullahs are Sherana, Neeli Kuch & Spin kuch. Besides these
three nullahs there are small nullahs which discharge into the Gomal River 40km
reach. Most of the nullahs observed during site visit are seasonal nullahs which
contribute during rainy season. These nullahs were observed having catchment
area in the adjacent mountains of much steeper slope hence carrying eroded
material during rainy and flash floods season. The bulk water discharge from
these contributing nullahs further speed up the water flow in the Gomal River
40km reach and resultantly more silt travels downstream with river flow into the
system.
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The project has shared three years record of river discharge, sediment, water
quality and Climatological Data Report of years 2014, 2015 and 2016 prepared by
Surface Water Hydrology Project. The record reflects that the 40Km stretch of the
Gomal River has a tendency to carry suspended sediment during the flood flows.
It also reflects that the watershed is unstable and heavy rainfall erodes the bed
material due to steep slope of the river.
Year-wise Suspended Sediment Concentration have following observed maximum
values. Three years maximum observed suspended sediment concentration in a
year is as below.
Year 2014 2015 2016
Maximum Annual observed value 7330(ppm) 28,250 18,000
Corresponding Discharge(m³/s) 208.4 545 475.5
Date of event April 5 July 31 August 7
Though, annual sediment transport computations data reflect a reduction in the
sediment yield at Kot Murtaza Station after the construction of Gomal Zam Dam
in the year 2011 onward, refer Appendix-D.
3.3 River Course
The Gomal River 40km stretch is of rugged terrain with minimal scattered
vegetation. The surrounding mountain range lacks vegetation cover hence
susceptible to erosion as a result of heavy rains during the monsoon. The river bed
slope is steep enough as river drops by one meter after every 154m stretch. The
downstream river bed level at Gomal Zam Dam is at elevation of 635 above mean
sea level (msl) and the invert level of under sluice at Diversion Weir (barrage)
location is at an elevation of 375.3 msl. This reflects steep bed slope of the Gomal
River that results in high velocity during flood seasons. The Gomal River is being
fed by hill torrents having steeper bed slope together with unstable geology.
In addition, due to the construction of Gomal Zam Dam and the Diversion Weir
(barrage) the regime of the Gomal River has been disturbed which requires
considerable time in regaining regime conditions (non-silting and non-scouring
condition). Till that time there will be scouring at one point and siltation at another
point within the 40km stretch that results in silt accumulation in front of the
diversion weir (barrage).
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4 Causes of Siltation in Canal System
From above discussions regarding the sources of siltation it is revealed that silt
travelling in 40km stretch of the Gomal River ultimately deposits / accumulates at
the upstream of diversion weir (barrage). About 300m upstream of the diversion
weir (barrage), the river course is filled with heavy deposit of coarse sediment as
observed. The diversion weir (barrage) is filled up to crest level with silt as
observed during the site visit. Such flood irrigation schemes do silted up on the
upstream of the diversion weir (barrage) and its entrance into the canal head
regulator are usually controlled with proper gate operations of the Under sluice
structure and of canal head regulator.
The provision of four gated under-sluice structure is to flush the deposited silt in
front of the canal head regulator back to the Gomal River on its downstream side
to regulate a relatively clean flow into the canal system.
The accumulated silt at diversion weir site enters the main canal and the
distribution system mainly due to following main reasons;
improper operation of the under sluice and canal head regulator gates due to
breakdown of the only available generator during (June-September) 2017
period and availability of only one gate operator who could not operate the
under sluice gates during flood event.
temporary blockages of canals and distributaries by the local farmers has been
observed during site visit including filling the canal trapezoidal section with
stones, bushes, trolley load of clay, clothes and similar, which results in the
deposition of suspended silt in the canal bed;
Following secondary reasons have contributed in aggravating the siltation issue;
Delayed handing over of the system to Provincial Irrigation Department who
has to conduct annual cleaning of the system;
Non-allocation of maintenance budget by the Provincial Irrigation Department
as complete system is not yet taken over from WAPDA;
Delayed hiring of Irrigation Department staff (baildars) whose job is to keep the
canal reach clear from weeds, bushes and report blockage by farmers;
Delayed Social Mobilization of the beneficiaries to apprise them of new canal
system operation and maintenance requirements; and,
Delayed implementation of watercourses which has to take due share of silt
transportation to the field;
It was informed that canal de-silting was carried out by WAPDA/FWO from
(April-August) 2016 before partial handing over of the system to GZID in October
2016.
These causes are briefly discussed in the sections to follow.
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4.1 Location of Diversion Weir
The location of existing diversion weir has been adjusted on the recommendation
of Hydraulic Model Study conducted at Hydraulic Research Station, Nandipur in
2010. As a result, the earlier suggested location in the Feasibility Study Report 1995
was shifted 360m downstream.
The Hydraulic Model Study recommendations included following two drawn
conclusions which are;
i. “The barrage structure as a whole or the crests of all the components of the barrage
must be raised at least 1m or 1.5m if feasible, to create sufficient pond at the barrage
thereby mitigating the sediment (silt) entry into the canal.”
ii. “If it is not feasible or possible to raise the level of the barrage at the 2nd location at
least by 1.0m then the Silt Ejector may be provided across the canal at a distance of
(300-400) m downstream of canal head regulator to eject the large amount of
sediment entering the canal at the Head Regulator.”
The Hydraulic Model Study recommendation was based on the assumption that
creation of an upstream pond might mitigate the sediment / silt entrance into the
canal.
In this respect, the provided design drawings have been reviewed which reflects
that basic concept of the Nandipur Hydraulic Model study has been incorporated
by raising the elevation of barrage crests by 1.0m.
4.2 Barrage Gate Operation
Barrage is provided with both manual and electric power operated gates for four
gated under sluice and three gated canal head regulator. Provision has been kept
to operate all gates either manually or with electric power. During floods, under
sluice gates can only be operated manually by two persons while one person can
operate the canal head regulator gate. A power generator is provided for gates
operation by FWO which they have earlier used during the construction period.
The provided generator requires frequent maintenance.
Normally, under sluice gates are kept closed with canal head regulator gates in
open status to divert the river flow into the canal for irrigation purpose. During
flood events, canal head regulator gates are kept closed to prevent silt entrance
into the canal while under sluice gates are raised to cross the flood peak and to
flush the accumulated silt on its upstream floor back to the river on the
downstream side. The canal head regulator gates are raised only when the flood
starts receding as it carries considerably less proportion of silt.
The visiting team has been informed that barrage gates operation was not possible
due to absence of required number of trained gate operators at site and also due to
breakdown of the provided generator during the last three months. The generator
was non-operational and has been recently repaired as per the collected
information. During this period 12 flood events have passed and are recorded by
the gate operator. Proper gate operation was not possible during the flood events
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due to breakdown of the available generator and presence of only one gate
operator during the mentioned period. This has resulted in considerable silt
entrance into the canal system during the last monsoon period floods as the gates
of the canal head regulator were not closed during flood events and the under
sluice gates were not operated.
During the visit, the team has been introduced with six staff members who were
recently appointed as barrage gate operator for round the clock presence of at least
2 gate operators at site. There exist gate operator room close to the barrage for
their stay at barrage site.
The visiting team felt a need of recently appointed staff training on proper gate
operation. At site rating curves of canal head regulator and of under sluice are
provided to operate gate as per requirements. Only one gate operator is found
familiar with the proper reading and use of the rating curves.
4.3 Local Irrigation Practices
In absence of watercourses, canal flow is being diverted from canal through
outlets by blocking the canal flow and by using inverted pipe syphon at fall
structures or even using pumping system by the farmers. This obstruction /
blockage to flow results in reduction of flow on downstream side, reduction of
flow velocity which ultimately leads to suspended silts deposit in the canal bed. A
very small number of farmers in close proximity of outlet have constructed raised
unlined watercourses in their own land. They do not provide water to other
neighbouring farmers from their watercourse or outlet. Only the well to do
farmers have arranged long pipes for irrigation of their land with syphons or use
of small pumps directly lifting water from the canals.
Such practices lead to unsystematic distribution of available water through raised
earthen canals against the contours for which the beneficiaries have to raise the
canal water level at outlets by canal blockage.
4.4 Local Siltation due to Blockage in the distribution system
As the local farmers of the area are habitual of using the traditional Rod Kohi (Spate
Irrigation) and try to get more water by Gandi system (creating temporary earthen
obstructions constructed across the bed of the canal). At different outlets it was
observed that farmers have obstructed water flows in the distributaries with
bushes, boulders and other materials to raise the water level for irrigation of their
undulating lands. In some distribution canals this kind of obstructions are placed
at different locations for the same purpose and by different farmers. These
obstructions reduce the velocity of flowing water and siltation occurs at the
upstream side of obstructions in the canal. This siltation is local and has no
significant impact on the canal operation.
On several distributaries, farmers at upstream outlets have blocked the
distributary to raise water for irrigating their undulating lands. The downstream
outlets are completely deprived from irrigation water. As a result of such actions
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canal banks are observed damaged at different locations with overflowing water.
This type of channel blockage is still in practice.
On Distributary No. 3 complete blockage is a permanent practice by the farmers of
the upstream outlets. The downstream farmers are socially and politically weak
and cannot remove the permanent blockage of canal by the farmers of the
upstream outlets. These downstream farmers informed that their water supply
was broken down and they have requested upstream farmers to allow water for
few days but they have refused. They are appealing to different authorities for
help to solve the problems but without any success until September 26, 2017.
On Distributary No. 10, water was completely blocked by upstream framers and
no water was given to outlet at RD 36858 (Kot Essa Khan) and below this point.
They were approaching different authorities to overcome this problem as of July 5,
2017.
The distributary No. 13 was also completely blocked and no water was available.
During the visit to this distributary (September 23, 2017) farmer informed that this
is the first day that water is flowing in distributary-13 during this season. The
water in the distributary was very turbid which confirmed farmer’s information
about its sudden opening. The flow measured at end of main canal comes out to
be 9 Cusecs.
4.5 Delayed Construction of Waran Canal & Watercourses
Due to delayed construction of Waran Canal and field watercourses the canal
system is not fully operational and due share of transported silt is not distributed
proportionally to the whole system. Due to delayed implementation of
watercourses the transported silt deposits in the bed of operational distributaries
and is not transported to the fields due to blockages by farmers. The operational
distributaries are showing more silt deposition due to delay in operation of whole
system and routine annual desilting is not yet practiced. During field visits to
WUAs, a consistent demand for an early construction of watercourses was raised
by all the beneficiaries.
4.6 Canal Operation Staff of GZID
GZID appointed 64 persons for canal operation who are deployed on the taken
over distributaries and the main canal. The appointed baildar is responsible for
about 3-km reach to remove canal obstructions, clean weeds, sediment in order to
maintain the canal flow up to the tail structure. Visit to the main canal and
distribution system indicated that performance of the GZID staff need to be
enhanced / improved by frequent visit of the irrigation officials to monitor /
inspect their staff performance. The landowners sitting at the head reaches of
distributaries are permanently blocking water and placing obstructions thus
diverting as much water as they want and depriving the downstream farmers of
their water rights in the presence of the shared heavy contingent of canal
operation staff of GZID.
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GZID has shown two files of complaints received and action taken to address the
canal blockage issue with the help of local authorities. Despite these actions, the
local are still using the old practice.
The visiting team is of the view that with the implementation of watercourses and
social mobilization of the beneficiaries, the matter will be gradually addressed
with passage of time.
4.7 Annual Cleaning and Maintenance of Canal System
Normally annual cleaning and de-siltation of canal system is practised during the
canal closure period (In Pakistan January is observed as closure period for canals).
It has been reported that no annual cleaning / maintenance has been done by
GZID due to non-availability of required budget with the Irrigation sub-division.
Currently, GZIP is not completely taken over by the Provincial Irrigation
Department on the plea that the implementation is not yet completed. There are
sites where the canal distribution system is damaged or is not high enough to
command the field. Therefore, discussions are in process among the stakeholders;
WAPDA, FWO and Provincial Irrigation Department to agree on the way-forward
on how to address the punch list prepared by the Irrigation Department indicating
damaged works of the system. As a result some of the distributaries including; RB
distributary, Khanwand distributary and tail portion of distributary 4 are non-
operational.
During the site visit, existing flow in the distributaries has been observed using
float method together with their existing free-board. The designed free board are
in line with the United State Bureau of Reclamation (USBR), though due to current
siltation it appears on lower side. The calculated observed discharge is tabulated
in Appendix-E
Provincial Irrigation Department staff are of the view that due to observed
damages, the system is not considered completed and they are not in a position to
takeover the damage or problematic distributaries. Till date, Provincial Irrigation
Department has takenover the Diversion Weir (barrage) and 7 distributaries from
distributary 6 to 13 with an exception of distributary 7. GZID further updated that
until the complete take over of the entire system, Operation and Maintenance
(O&M) budget cannot be allocated by the Provincial Irrigation Department. GZID
has prepared a PC-I for the review and approval of authorities. A copy has been
attached as Appendix-F which do represents their estimated canal desilting
budget.
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5 Recommendations for Silt Control in Gomal Zam
Based on the above detailed discussions it has been concluded that main source of
silt entry into the canal and canal distribution system are following:
1. Mainly the silt transported by Gomal River 40km stretch (between dam and
barrage) accumulates at the upstream of diversion weir, enters the canal
system due to improper barrage operation.
2. Deposition of suspended silt in the canal system as a result of farmers
obstructing canal flow by temporary blockage to divert the flow towards their
fields. As a result flow velocity reduces and suspended silt settles in canal bed
instead of being transported to the fields.
In order to control the situation the required remedial measures are categorized in;
short term measures and long term measures.
5.1 Short-Term Measures
Suggested short terms measures include the following:
5.1.1 Proper Operation of Barrage Gates
WAPDA do provide a Gate Operational Manual which guides on the proper
operations of the canal head regulator gates and under-sluice gates during
normal flow conditions and flood events.
The newly hired gate operators of GZID should be trained in gate operation as
the silt enters from the upstream river side into the canal. This also requires
ensuring the hired staff presence at site. As per information, normally short
duration floods occurs at night, hence presence of operators round the clock is
required to monitor floods and operate the under sluice and canal gates
accordingly.
Although the barrage site is well equipped with the required accessories and
electrical fittings, however power supply from national grid is not available
and resultantly, the barrage lies in complete dark during night times. It is
recommended that provision of solar power must be made for the operation of
the installed lights at barrage site for use during night times and flood
emergencies.
The existing power generator at barrage site is in deteriorated condition and
require frequent repair & maintenance. This generator may be replaced with a
new power generator of appropriate capacity. The power generator laying
under open sky must be properly installed and protected in a generator room.
Moreover, availability of fuel for generator use must be ensured on site at all
times.
GZID should remove the accumulated silt on upstream of the canal head
regulator either by flushing method or by using earth works machinery.
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Provincial Irrigation Department should release Operation and Maintenance
fund for barrage operation and maintenance without further delays at least for
the taken over distributaries and barrage.
GZID may review the possibility of extending the upstream floor at El 376.50m
up to the upstream point of divide wall between (under sluice and canal head
regulator) refer drawing Nos. GZD-BA-GD-008, GZD-BA-GD-010 and GZD-
BA-GD-011 for better understanding. The design drawings reflect the
upstream floor of canal head regulator at El 376.5m is of 20m length only. The
canal head regulator approach channel then drops down to same level of
under sluice upstream floor which is at EL 375.8m.
We are of the opinion that due to same upstream bed elevation of EL375.8m,
the sediments / silt entered in the canal head regulator approach channel
cannot be removed with the operation of under sluice gates due to an existing
divide wall between under sluice and canal head regulator. With the raising of
the upstream bed at current El 375.8m to El 376.5m by an approximate length
of 17m (up to the start of divide wall) silt entrance into the canal head
regulator approach channel will be reduced and a low level flow channel will
be guided towards the under sluice. This will create helicoidal flow situation
with heavy sediment / silt will be guided to the under sluice and
comparatively clean flow towards the canal head regulator. This suggested
raised extension will act as a skimming weir that will reduce silt entrance into
the canal and guide the deposited silt towards the under sluice. Refer
Appendix-G for better understanding the suggested improvement.
5.1.2 Taking Over of the Entire GZIP by Provincial Irrigation Department
Dedicated efforts should be taken by all stakeholders to create a situation in which
Provincial Irrigation Department takes over the remaining distribution system of
GZIP. Currently, the system has been partially taken over by the Provincial
Irrigation Department and discussion are underway for the rest. It is expected,
that most of the issues will be addressed with the complete taking over of the
GZIP by the Provincial Irrigation Department. As this will start allocation of
Operation and Maintenance funds by the department which is currently not
available under any head.
5.1.3 Removal of Obstructions in Canal System
GZID should ensure removal of all temporary & permanent obstructions from the
canal distribution system. GZID should enforce functioning of the entire
distribution system by all available means under the law. The field staff of GZID
shall regularly monitor outlets discharge at the distributaries and must ensure the
availability of water up to the tail portion in the taken over system portion.
GZID should capitalize on the on-going command area project through close
coordination with project staff to utilize farmer’s organizations for smooth canal
operation.
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5.1.4 Social Awareness of Farmers / Locals
As the farmers are habitual of traditional Rod Kohi (spate irrigation) system and try
to get more water stored by using their traditional Gandi system for diverting
water from the canals. Social awareness and sensitization of local farmers is
required to educate them for getting irrigation water from canals through
appropriate structures, practices and further usage and advantages of canal
irrigation system.
5.1.5 Maintenance of Canal Berms
Canal berms are not maintained on large sections of many distributaries. At some
locations it has been observed that both sides of the distributaries are submerged
in thick bushes and it appears that water is flowing through bushes. These bushes
are extending in canal and on the canal berms. They may cause hindrance and
temporary blockages in the normal flow of water and cause siltation in the canal.
Maintenance of canal berms be ensured by cutting of all bushes by the field staff of
GZID.
5.1.6 Routine Canal Cleaning
Annual silt cleaning of canals is carried out in the country by Irrigation
Department in the month of January for which canal closure dates are notified.
GZID will also carry out annual canal cleaning this year after issuance of prior
notification to farmers.
GZID estimated the existing annual canal cleaning cost of up to Rs. 9.6 million in
September 2017. Annual cost of cleaning is part of the O&M budget of the canal
system and is attached as Appendix-F. The task of canal desilting should be
carried out jointly by Irrigation Department and farmers to inculcate sense of
ownership among water users.
5.1.7 Completion of Waran Canal & Watercourses
Delays in completion of Waran canal and of field watercourses under Command
Area Development activities have equally contributed in worsening the canal
siltation problem. Usually, the suspended silt enters the fields through the
watercourses. Currently, in the absence of these watercourses, the beneficiaries are
blocking the canal at their own will to divert the flow towards their field without
considering the contours. There are sites where farmers are diverting the flow
against the contour resulting in complete blockage of canal system.
It is therefore suggested that remaining work of Waran canal and watercourses be
expedited for full irrigation system operation and distribution of share of silt in the
irrigation system.
5.2 Long-Term Measures
Following long term measures could be considered if the siltation issue is not
addressed with the short terms measures;
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5.2.1 Provision of Silt Ejector
Nandipur Hydraulic Model Study has suggested that raising of barrage by 1.0m to
create sufficient pond upstream of the barrage so that the sediment entry into the
canal might be mitigated. Incase, sedimentation / silt issue is not mitigated by
undertaking short terms measures then the suggested option of Silt Ejector may be
considered across the canal at a distance of 300-400m downstream of canal
regulator to eject the sediments entering the canal.
5.2.2 Watershed management for 40km stretch
Another possibility is to minimize the concentration of sediments by afforestation
of the unstable hill torrents within the 40km stretch. This includes afforestation
together with other structural and non-structural interventions to reduce soil
erosion.
This option is considered difficult under the present volatile law and order
situation of the area. If this option is considered, extensive efforts will be required
for plantation in the area covered with rocks.
Detailed study will be required for the identification of specific water resistant
plants species according to climatic and geological conditions of the area and
plantation in the watershed as the area requiring plantation is quite large.
Similarly, other structural options may also be explored such as cascade of barriers
made of local stones, wood or bushes to slow down the erosive velocity of hill
torrents.
5.2.3 Construction of Check Dams
In order to reduce the Gomal river bed slope, one option could be provision of
check dams at regular intervals. The Gomal river bed drops from elevation 635.0m
msl to El 375.8m msl at barrage under sluice. The 260m drop could be utilized by
providing multipurpose check dams in the river bed including micro hydropower,
irrigation and similar. This suggestion involves fresh surveys and studies to
determine the extent to which these check dams could control the sedimentation
over the years. Extensive studies and environmental impact assessment will be
required to consider this option. However, construction of check dams in the
waterways / nullahs which are contributing flash floods and carry sediments and
debris from the mountains in to the River at different locations could be a better
option to counter erosion by reducing water flow velocity and gradually plugging
off the waterways.
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6 Conclusion
Based on the detailed discussions above it is concluded that;
Mainly the silt transported by Gomal River 40km reach accumulates at the upstream of
diversion weir, enters the canal system and deposition of silt in canal bed occurs due to
improper gate operation and poor irrigation practices.
The Gomal Zam Dam itself is not contributing any silt into the Gomal River. The
Gomal River 40km stretch (between dam and barrage) is the primary source of
siltation. The existing nullahs/streams in the watershed of 40km stretch contribute
silt during floods. Most of the existing nullahs are seasonal and have steeper bed
slope, hence more silt transportation.The Gomal river 40km reach bears steep
slope as the elevation drops by 260m between dam downstream and barrage
upstream. The silt deposited in Gomal river 40km strectch by existing
nullahs/streams travels with river flow and accumulates at upstream of diversion
weir.
The accumulated silt at diversion weir upstream enters the main canal due to
improper operation of barrage / diversion weir gates. The barrage gates operation
has been affected due to number of reasons incuding less staff availability, electric
power generator break-down, non-availability of barrage gate operation manual
that guides when to close the canal head regulator gates and open the under sluice
gates and similar. In distributarory canals the silt is deposited by poor irrigation
practices followed by the local farmers.
The other causes of silt accumulation in the distribution system include the
delayed construction of Waran Canal & watercourses, absence of annual cleaning
and maintenance of canal system due to non-availability of funds, delayed social
mobilization of the beneficiaries on proper operation of new canal system, delayed
handing over of the system to Provincial Irrigation Department.
Short term remedial measures are suggested to address current siltation while
suggested long term measures will be under taken at a later stage after proper
study, if short term measures do not address the siltation issue. It is expected that
implementation of short term measures will improve the situation of silt
transportation and its deposition in the canal system.
Once the canal system is fully operational and short term measures undertaken,
then assessment of silt may be considered again at a later stage considering
feedback from locals and Provincial Irrigation Department. If the situation still
persist then long term measures be considered which requires extensive studies
before reaching to any decision on funding possible long term interventions.
Regarding the economic implications for short term measures, most of the
mitigation measures does not require cost rather management by the Provincial
Irrigation Department. Major element involving cost factor is de-silting of existing
distributaries for which PC-1 details shared by Irrigation Department have been
appended in Appendix-F. As the quantum of silt accumulated in the canal system
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is not possible to assess due to to prevailing security situation and time constraints
the cost estimation for desilting shared bt Irrigation department has been adopted.
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7 Limitations of the Study
This Siltation Rapid Assessment Overview Report has following limitations;
USAID requirement for study was to provide an overview of the siltation
issue;
Cost benefit analysis have not been included in the report due to non-
availabilty of details regarding production of command area. As the
watercourses have not been constructed consequently system is not fully
operational. Moreover, command area development incuding land levelling
and similar activities have not been started therefore, conclusion about
command area production cannot be arrived;
The prevailing security conditions of the area doesn’t permit for detailed
assessment of the canal system;
The contents of report have been based primarily on site visit and discussions
held with stakeholders. Further the documents/reports shared by stakeholders
have been reviewed.
Actual quantum of silt deposition are normally carried out by Siltation
Laboratories. Our assessment is based on the report prepared by SURFACE
WATER HYDROLOGY PROJECT for WAPDA on the topic, “RIVER
DISCHARGE, SEDIMENT, WATER QUALITY AND CLIMATOLOGICAL
DATA REPORT.
Long term measures as discussed above, if needed to consider, will require
detailed study of siltation issue carried out by specialised agency before arriving at
any decision.
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Appendix A
Minutes of Meeting with Stakeholders
Halcrow Pakistan (Pvt) Limited
3rd Floor, Nawa-e-Waqt House, Mauve Area, Sector G-7/1, Zero Point, Islamabad, Pakistan Tel +92 51 220 3451-55 Fax +92 51 220 3462 [email protected], www.halcrowpk.com
Meeting Record
Halcrow Pakistan (Pvt) Limited (An independent Company formerly part of Halcrow Group.) Registered office: 3rd Floor, Nawa-e-Waqt House. Mauve Area,
Sector G-7/1, Zero Point, Islamabad, Pakistan. Company Registration No. 0030400, PEC Registration No. CONSULT/712.
Project A-E Services for Monitoring and Milestone
Verification of USAID-Funded Waran Canal
and Gomal Zam Dam Command Area
Development Program in Khyber
Pakhtunkhwa
Date September 19, 2017
Ref
Subject Meeting regarding Siltation Issue in GZIP Page 1 of 5
Venue WAPDA’s Rest House, Chashma Right Bank Canal (CRBC), DI Khan
Date held September 19, 2017
Present WAPDA
Abdullah Khan, Senior Engineer (SE)
Adnan Khan, Junior Engineer (JE)
FWO & AREAA
Maj. Atif Nasim Awan, FWO
Syed Shafqat Abbas, Accountant FWO
M. Ishaq Bhatti, Project Manager AREAA
Irrigation Department
Tariq Ali Khan, XEN Irrigation
Rizwan, SDO Irrigation
Qazi Shafqat, Sub-Engineer
Management Consultant (MC)
Syed Akhter Hussain, Project Manager
Sharifullah, Design Engineer
Akhter Abbas, IWCE
Rehmatullah, ARO
Muhammad Sadiq, Environmental Specialist
Halcrow Pakistan (HPK)
Fazal Mahmood, Chief of Party (COP) WC & GZD-CADP
Mian Zia-uddin, Irrigation Engineer (IE)
Saifur Rahman Sherani, Sociologist (SC)
Atif Murtaza, Field monitor (FM)
Munawar Saeed, Field Inspector (FI)
Haroon Latif, Project Security Manager (PSM
Apologies None
Record of meeting about Meeting regarding Siltation Issue in GZIP Page 2 of 4
No. Discussion Action
1. A meeting regarding Siltation Issue in Gomal Zam Irrigation
System was held at WAPDA’s Rest House, Chashma Right Bank
Canal (CRBC), DI Khan.
2. Introduction: SE WAPDA, thanked the participants of the
meeting to attend the meeting. CoP briefed the participants
about the siltation overview report requirements by USAID and
asked the questions regarding primary sources of siltation,
locations where siltation occurred, major causes/reasons of
siltation and remedial/mitigation measures required to control
situation. CoP requested XEN Irrigation to explain the siltation
problem to meeting participants.
3. Primary Sources:
XEN Irrigation briefed the participant’s regarding siltation issue
in GZIP. He told that primarily siltation occurs in 35 Km reach
which travels up to barrage / diversion weir and then in main
canal and distributaries. During rain muddy water from
mountains enters in 35 Km reach. Dam is not contributing any
silt as clean water has been observed from dam discharge.
Mainly silt enters from diversion weir into the canal system.
MC agreed with the observations shared by XEN and further
added that mainly three nullahs namely ; Sherana, Neeli Kuch &
Spin Kuch are contributing silt in 35 Km reach besides some
small nullahs. It was further shared that normally short duration
(1 to 1.5 hrs) floods contribute to silt accumulation in 35 Km
reach.
4. Locations: CoP asked XEN regarding the locations in canal
system where silt accumulation has occurred. XEN shared that
normally silt accumulates at the U/S of diversion weir and then
enters into the canal system. He further shared details of silt
observed in main canal and distributaries.
5. Causes:
CoP asked the causes for silt accumulation at U/S of diversion
weir and canal system.
MC shared that the main reason for silt accumulation at U/S of
diversion weir is improper control of regulation of the under
sluice gates. MC further shared that due to breakdown of
generator the under sluice gates were non-operational since last
three months. It was pointed out by MC that non-presence/less
staff availability for gate operation has been observed during
Record of meeting about Meeting regarding Siltation Issue in GZIP Page 3 of 4
No. Discussion Action
their visits. It was further shared by MC that trained persons
should be deputed for gate control at diversion weir.
XEN didn’t agreed with MC that accumulation of silt at U/S of
diversion weir is due to improper control of under sluice gates.
However, he confirmed that generator was out of run for some
time but now repair work has been fixed. He share that control
of under sluice gates never remained un-attended however,
hiring of more staff for gate operation is under process.
CoP asked regarding the location of diversion weir. MC
explained that the Feasibility study report shows weir location
400m upstream as compared with current location. Current
location is adjusted after a model study report from Nandipur
research station. CoP requested to share the research report
received from Nandipur.
XEN & MC further shared that as the farmers/locals are habitual
of Rod Kohi (Spate Irrigation) system and try to get more water
by adopting Gandi system which creates hindrance to canal flow
and reduction in flow velocity resultantly accumulation of
suspended silt in canals.
6.
Remedial Measures: CoP asked the participants for possible
short and long term remedial measures required to control the
silt accumulation in the canal system and diversion weir.
The participants shared the following remedial measures for
consideration:
MC proposed De-silting/cleaning of accumulated silt at
diversion weir. Further under sluice gates should remain open
in order to control for silt accumulation at U/S of diversion weir
CoP asked about operation manual for proper control of gates
operation at diversion weir. XEN informed that no Operation
manual exists and need to be developed for proper gate
operation by the Designer.
MC suggested that Staff/operators training is required, further
staff needs to be increased for proper sluice gate operation. MC
also suggested for routine/annual cleaning of canal system by
Irrigation department. Moreover Canal needs to be closed
during flood to control silt.
WAPDA suggested that Irrigation Department to be equipped
with funds for routine maintenance/cleaning as no funds have
been allocated for maintenance.
Record of meeting about Meeting regarding Siltation Issue in GZIP Page 4 of 4
No. Discussion Action
The participants agreed that education of farmers/locals for use
of canal system, social mobilization and awareness is required as
the gandi system is still in practice. Further it was suggested that
remaining work on canal completion to be expedited as the
incomplete canal system is also contributing to silt
accumulation.
MC and WAPDA suggested for long term measures to be
considered by:
Watershed management by plantation/vegetation in the
catchment of 35 Km reach
And construction of Check Dams at regular intervals to control
silt in the Gomal river 35km stretch.
7. Conclusion: The meeting ended with the note of thanks by CoP
and proposed site visit details were shared with participants to
accompany during site visits.
Author:
COP:
Halcrow Pakistan (Pvt) Limited
3rd Floor, Nawa-e-Waqt House, Mauve Area, Sector G-7/1, Zero Point, Islamabad, Pakistan Tel +92 51 220 3451-55 Fax +92 51 220 3462 [email protected], www.halcrowpk.com
Meeting Record
Halcrow Pakistan (Pvt) Limited (An independent Company formerly part of Halcrow Group.) Registered office: 3rd Floor, Nawa-e-Waqt House. Mauve Area,
Sector G-7/1, Zero Point, Islamabad, Pakistan. Company Registration No. 0030400, PEC Registration No. CONSULT/712.
Project A-E Services for Monitoring and Milestone
Verification of USAID-Funded Waran Canal
and Gomal Zam Dam Command Area
Development Program in Khyber
Pakhtunkhwa
Date September 20, 2017
Ref
Subject Meeting regarding Siltation Issue in GZIP Page 1 of 3
Venue Gomal Zam Irrigation Division Office, D.I.Khan
Date held September 20, 2017
Present Irrigation Department
Tariq Ali Khan, XEN GZDIP (XEN)
Khushal Khan, XEN CRBC (XEN-I)
Rizwan, SDO Irrigation (SDO)
Qazi Shafqat, Sub-Engineer (SE-I)
Inayat Ullah , Sub-Engineer (SE-II)
Mushtaq Ahmed, Zdr. Rtd. (ZR)
Halcrow Pakistan (HPK)
Fazal Mahmood, Chief of Party (COP) WC & GZD-CADP
Mian Zia-uddin, Irrigation Engineer (IE)
Atif Murtaza, Field Monitor (FM)
Munawar Saeed, Field Inspector (FI)
Apologies None
No. Discussion Action
1. A meeting regarding Siltation Issue in Gomal Zam Irrigation
System was held with Irrigation Division Gomal Zam at their
office in DI Khan.
2. Introduction: CoP thanked the participants of the meeting to
attend the meeting. CoP briefed the participants about the
siltation overview report requirements by USAID and asked the
questions regarding primary sources of siltation, locations where
siltation occurred, major causes/reasons of siltation and
remedial/mitigation measures required to control situation.
Record of meeting about Meeting regarding Siltation Issue in GZIP Page 2 of 3
No. Discussion Action
3. Design Issues:
XEN Irrigation briefed the participant’s regarding the design
issues observed. He explained that mainly three issues
pertaining to design. Major issue is less free board provided in
the canals. Normally the accumulation of silt is compensated by
free board but 6 to 9 inches free board has been provided which
is not sufficient. The other issue related to design are lack of
provision of escape structures and availability of required
demand discharge at canal head regulator.
CoP inquired about the water requirement throughout the year.
Following details were shared by XEN:
January ------------ Closure
Feb. to March----- 24 cumecs
April to Aug. ------12-16 cumecs
Sep. to Dec. ------- 24 cumecs
CoP inquired about the crops being cultivated by farmers/locals.
XEN shared that Rabi season main crop is Wheat, while Kharif
season crops include Maize, Sugar Cane, Millet, Chick Peas,
Melon and Grass.
XEN further explained that difference in GCA & CCA is
considerable. Reduction factor in GCA has been applied
randomly without considering ground conditions which will be
problem for farmers in future.
XEN suggested for the involvement of Irrigation department at
the time of defect liability period in order to highlight the
shortcoming in canal system.
4. Operational Issues: CoP asked XEN regarding the operational
issues being faced.
XEN shared that barrage/ diversion weir control manual
has not been provided. He added that proper calibration of
canal system has not been done. He further shared that Punch
list developed at the time of handing over has not been
implemented. Most of the issues were mentioned in the punch
list for system improvement but WAPDA hasn’t agreed on
punch list developed.
CoP advised XEN to revisit the punch list developed and try to
reach on consensus mutually. CoP further shared that issue of
operation manual required for proper gate operation has already
been discussed in joint meeting with Management Consultant &
WAPDA.
Record of meeting about Meeting regarding Siltation Issue in GZIP Page 3 of 3
No. Discussion Action
XEN shared that Generator installed for gate operation is 5 years
old, affects performance and needs replacement.
CoP asked about the routine/annual maintenance of canal being
done for the canals handed over by WAPDA. XEN explained
that he has requested the department for allocation of budget
but no allocation has been made yet.
5. Cost estimates :
CoP inquired regarding cost estimates for the cleaning of canal
system.
XEN shared the cost estimate of PKR 10 M inclusive of
maintenance and system improvement. CoP inquired regarding
the methodology adopted for the preparation of cost estimates.
XEN shared that normally de-silting budget is prepared on
experience basis. Normally the time in hours required to clean
the canals from silt by excavator is base point for estimation.
Actual survey for quantification is done before the start of work
and actual quantity may vary.
6. Conclusion: The meeting ended with the note of thanks by CoP
and proposed site visit details were shared with participants to
accompany during site visits.
Author:
COP:
A-E Services for Monitoring and Milestone Verification of USAID-Funded Waran Canal and Gomal Zam Dam Command Area Development Project in Khyber Pakhtunkhwa
GZIP-Siltation Rapid Assessment Overview Report
November 2017 HPK
Appendix B
Visit Photographs
Group photo of HPK, Irrigation and MC designer team at Gomal Zam Dam power house site
View of Clear and clean water supply from bottom outlet of Dam
Stream contributing in main river in 40 KM stretch
Main river view at Kot Murtaza
Group photo of Gate operators of diversion barrage
Upstream and downstream view of ogee weir of diversion barrage
Upstream view of canal Regulator gravel base sediments deposited at front of gates
View of silt flushing after opening the gates of under sluice
Power Generator in poor condition for mechanical operating of diversion barrage Gates
Mekali Wah Distributary start reach outlet R/S damaged and L/S Panel also broken
RB distributary head regulator view discharge calibration not yet marked at discharge point
RB distributary head reach fully silted up to lining top
Khan Wand distributary head regulator discharge Calibration marked at discharge point
Khan Wand distributary head reach having silt and washed away at upstream and downstream of aqueduct
D1-R1 distributary head reach view HPK team members collecting information from
the farmer on silt at D1-R1 distributary
Distributary no 1 Calibration marked at discharge point
Distributary no 1 de-siltation done by farmers
HPK Sociologist getting information from the farmer of Distributary No 1
Head reach view of distributary no 2
Head regulator of distributary No 3 Distributary No 3 head reach de-siltation done by
contractor FWO about 1.5 year ago
Silt and Jungle in Distributary No 4 head reach Silt berm in Distributary No 5
Head regulator of Distributary No 6 Farmers taking water by installing inverted pipe
syphon at Distributary # 6
Water blockage at Distributary No 6 Outlet no 22341/R
Distributary No 7 head reach
Distributary No 8; Completely silted-up near Kulachi road crossing
Irrigation Department Baildaar showing silt being deposited in bed of Distributary No 9
Distributary No 10 de-silted material on both banks
Distributary No 11 RD 02+380
View of Distributary No 12 Minor de-siltation done by the farmers
Discharge measurement at Head regulator of Distributary No 13
Distributary No 13 Head reach de-silted material on both banks
Main canal Silt and vegetation at RD 59+403
Meeting With WAPDA, Management Consultant, FWO and Irrigation Department
Meeting with Irrigation Department
A-E Services for Monitoring and Milestone Verification of USAID-Funded Waran Canal and Gomal Zam Dam Command Area Development Project in Khyber Pakhtunkhwa
GZIP-Siltation Rapid Assessment Overview Report
November 2017 HPK
Appendix C
Documents received and reviewed
No. Title of Document Type Source Date
Received
1 Feasibility Study Report 1995 of
multipurpose Gomal Zam Dam and
irrigation system
Report WAPDA Sep 15, 2017
2 Detailed Project Report Design of
Diversion Barrage of Gomal Zam Dam
Irrigation Component
Report Do Sep 15, 2017
3 GZDP River discharge, Sediment, Water
quality and Climatological Data Report
for the year 2014 & 2015
Report Do Sep 15, 2017
4 GZDP River discharge, Sediment, Water
quality and Climatological Data Report
for the year 2016 & 2017
Report do Sep 15, 2017
5 GZDP-02 Irrigation Component
Operation and Maintenance Manual of
Canal and Gated Equipment
Report Gomal Zam
Irrigation Division
Sep 20, 2017
6 List of AOM&R works in respect of
Gomal Zam irrigation Division D I Khan
during 2017-2018
Document do Sep 20, 2017
7 Statement Showing area Rod Kohi &
Related Gomal Zam Canal network.
Gomal Zam Irrigation Division D I
Khan
Document do Sep 20, 2017
8 Siltation of Distributaries in the
jurisdiction of Gomal Zam sub Divison
No 2
Document do Sep 20, 2017
9 Comprehensive Model of Diversion
Barrage Below Gomal Zam Dam
(Hydraulic Model Study)IRII&PD GO
Punjab
Report WAPDA Sep 27, 2017
A-E Services for Monitoring and Milestone Verification of USAID-Funded Waran Canal and Gomal Zam Dam Command Area Development Project in Khyber Pakhtunkhwa
GZIP-Siltation Rapid Assessment Overview Report
November 2017 HPK
Appendix D
River Discharge, Sediment, Water Quality record
A-E Services for Monitoring and Milestone Verification of USAID-Funded Waran Canal and Gomal Zam Dam Command Area Development Project in Khyber Pakhtunkhwa
GZIP-Siltation Rapid Assessment Overview Report
November 2017 HPK
Appendix E
Measured Canal Discharges
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Distributary
No.RD From RD To
Flow Q
(m³/s)
Velocity
V (m/s)
Free
Board (m)
Bed Width
(m)
Flow Depth
(m)
Total
Depth (m)
Velocity
(m/s)
Free Board
Observed ( m)Silt Depth (m)
Flow
Depth
Flow
Area
Flow Observed
without silt Q1
Flow
Depth
Bed
Width
Flow
Area
Flow Observed
with silt Q2
Difference
Q1-Q2
4 0+050 0+360 0.683 0.41 0.15 2.00 0.64 0.79 0.530 0.35 0.15 0.44 1.0736 0.569 0.290 2.300 0.751 0.398 0.171
5 0+109 1+009 1.733 0.70 0.20 2.75 0.72 0.92 0.79 0.15 0.15 0.77 2.7104 2.141 0.620 3.050 2.275 1.797 0.344
6 0+150 1+000 4.086 0.81 0.25 3.50 1.10 1.35 0.78 0.15 0.15 1.20 5.6400 4.399 1.050 3.800 5.093 3.973 0.427
7 0+00 0+311 1.189 0.89 0.18 0.90 0.79 0.97 1.40 0.45 0.15 0.52 0.7384 1.034 0.370 1.200 0.581 0.813 0.220
8 0+00 0+302 1.286 0.65 0.18 2.50 0.63 0.81 0.76 0.30 0.10 0.51 1.5351 1.167 0.410 2.700 1.275 0.969 0.198
9 0+00 0+133 0.589 0.58 0.15 1.00 0.62 0.77 0.58 0.20 0.15 0.57 0.8949 0.519 0.420 1.300 0.722 0.419 0.100
DESIGN DATA (AS BUILT DRAWINGS)
A-E Services for Monitoring and Milestone Verification of Waran Canal and GZD-CADP in KP
FIELD DATA CALCULATIONS
Without Silt With Silt
A-E Services for Monitoring and Milestone Verification of USAID-Funded Waran Canal and Gomal Zam Dam Command Area Development Project in Khyber Pakhtunkhwa
GZIP-Siltation Rapid Assessment Overview Report
November 2017 HPK
Appendix F
Data Received from GZID
AM&R PROGRAMME / WORKS / PC-I FOR THE YEAR 2017-18. GOMAL ZAM IRRIGATION DIVISION DIKHAN.
S# Name of Circle Division Circle / Division wise AM&R Programme for the Year 2017-18
042203 Canals
107105-Floods
042250-Others/L.I.S
042204-T/Wells
042202-Dams
042205-T&F
Total (3to8)
1 2 3 4 5 6 7 8 9
1 Gomal Zam Irrigation
Division DIKhan
(DIKhan Irrigiation
Circle DIKhan)
21.45
0
-- -- -- -- -- 21.450
G.Total 21.45
EXECUTIVE ENGINEER, Gomal Zam Irrigation Division DIKhan
GENERAL ABSTRACT OF COST
Sl.No Name of work Desiltation Other closure works/Non
Closure Work
G.Total
1 AOM&R and special repair of any kind of work for Gomal Zam Irrigation Canal Network in District DIKhan & Tank during 2017-18.
9.60 11.85 21.450
Grand Total 21.450
EXECUTIVE ENGINEER, Gomal Zam Irrigation Division DIKhan
LIST OF AOM&R WORKS IN RESPECT OF GOMAL ZAM IRRIGATION DIVISION DIKHAN DURING 2017-18.
Sl.No
Closure Work Rs
I. Desiltation 1 Predical clearance of U/S Approaches of Barrage at Kot Murtaza
(pre & after moon soon)
Rs.900000/-
1 Desiltation of main canal RD 00-25000 (m) in reaches Rs.300000/-
2 Desiltation of main canal RD 25000-60500 (m) in reaches Rs.500000/-
3 Desiltation of Disty Khan wand 00- tail in reaches Rs.300000/-
4 Desiltation of Disty Makali wah 00- tail in reaches Rs.250,000/-
5 Desiltation of Disty D1R1 00- tail in reaches Rs.300000/-
6 Desiltation of Disty No.1 00- tail in reaches Rs.250,000/-
7 Desiltation of Disty No.2 00- tail in reaches Rs.300000/-
8 Desiltation of Disty No.3 00- tail in reaches Rs.400000/-
9 Desiltation of Disty No.4 00- tail in reaches Rs.500000/-
10 Desiltation of Disty No.5 00- tail in reaches Rs.400000/-
11 Desiltation of Disty No.6 00- tail in reaches Rs.700000/-
12 Desiltation of Disty No.7 00- tail in reaches Rs.500000/-
13 Desiltation of Disty No.8 00- tail in reaches Rs.800000/-
14 Desiltation of Disty No.9 00- tail in reaches Rs.500000/-
15 Desiltation of Disty No.10 00- tail in reaches Rs.800000/-
16 Desiltation of Disty No.11 00- tail in reaches Rs.700000/-
17 Desiltation of Disty No.12 00- tail in reaches Rs.700000/-
18 Desiltation of Disty No.13 00- tail in reaches Rs.500000/-
Total Rs.9600000/- II. Other Closure Work
1 Repair to Damaged lining of Main Canal RD 00-25000 Rs.500000/-
2 Repair to Damaged lining of Main Canal RD 25000-60500 Rs.600000/-
3 Repair to Damaged lining Disty Makali Wah - Disty No.2 in reaches Rs.500000/-
4 Repair to Damaged lining Disty No.3 - Disty No.5 00- tail in reaches Rs.500000/-
5 Repair to Damaged lining Disty No.6 - Disty No.8 00- tail in reaches Rs.550000/-
6 Repair to Damaged lining Disty No.9 - Disty No.13 00- tail in reaches Rs.600000/-
7 Repair to Damaged Masonry Structure of Main Canal RD 00-25000 Rs.250,000/-
8 Repair to Damaged Masonry Structure of Main Canal RD 25000-60500 Rs.250,000/-
9 Repair to Damaged Outlets Disty Makali Wah to Disty No.2
00- tail in reaches
Rs.200000/-
10 Repair to Damaged Outlets Disty No.3 to Disty No.5 00- tail in reaches Rs.150,000/-
11 Repair to Damaged Outlets Disty No.6 to Disty No.8 00- tail in reaches Rs.300000/-
12 Repair to Damaged Outlets Disty No.9 to Disty No.13 00- tail in reaches Rs.300000/-
13 Repair to Electrical/Mechanical Equipment of Diversion Barrage at Kot
Murtaza i/c alternate energy system/Generator etc.
Rs.400000/-
14 Painting of gates of Head Regulator & under sluice i/c Railing and littering
Of gauges at Diversion barrage
Rs.150,000
Total Rs.,5250,000/-
III. Non Closure Work 1 Repair to Canal Petrol Road/Rain Cuts along Main Canal RD 00-25000 (m)
in reaches
Rs.400000/-
2 Repair to Canal Petrol Road/Rain Cuts along Main Canal
RD 25000-60500 (m) in reaches
Rs.500000/-
3 Repair to Canal Petrol Road/Rain Cuts along Disty Makali Wah to
Disty No.2 in reaches
Rs.450,000/-
4 Repair to Canal Petrol Road/Rain Cuts along Disty No.3 to
Disty No.5, in reaches
Rs.350,000/-
5 Repair to Canal Petrol Road/Rain Cuts along Disty No.6 to
Disty No.8, in reaches
Rs.500000/-
6 Repair to Canal Petrol Road/Rain Cuts along Disty No.9 to
Disty No.13, in reaches
Rs.600000/-
7 Restoration of occasional breaches in Main Canal
RD 00-25000 (M) in reaches
Rs.300000/-
8 Restoration of occasional breaches in Main Canal RD 25000-60500 (M) in
reaches
Rs.400000/-
9 Restoration of occasional breaches in Disty Makali Wah to Disty No.2, in
reaches
Rs.250,000/-
10 Restoration of occasional breaches in Disty No.3 to Disty No.5 in reaches Rs.300000/-
11 Restoration of occasional breaches in Disty No.6 to Disty No.8 in reaches Rs.450,000/-
12 Restoration of occasional breaches in Disty No.9 to Disty No.13 in reaches Rs.500000/-
13 Restoration of breach in Main Canal at RD.34+450 Rs.150000/-
14 Restoration of breach in Disty No. 4 at RD.8+500-8+520 &
RD.10+0-8+520
Rs.150000/-
15 Restoration of breach in Disty No. 5 at RD.6+00 and 10+100 Rs. 100000/-
16 Restoration of breach in Disty No. 7 at RD.03+045 – 03+057 Rs. 225000/-
17 Restoration of breach in Disty No. 9 at RD.05+245 – 05+251 L/S & R/S Rs. 125000/-
18 Restoration of breach in Disty No. 11 at RD.08+513 – 08+530 L/S & R/S Rs. 600000/-
19 Restoration of breach in Disty No. 12 at RD.01+140 R/S Rs. 100000/-
20 Repair/Renovation of Residential/non Residential(office + Barrage) Building. Rs. 150000/-
Total Rs.66,00000/-
G .Total (Closure & Non Closure Works) Say:-
Rs.21450000/- Rs.21.450 (M)
SUB DIVISIONAL OFFICER Gomal Zam Irrigation Sub Division No.I,
D.I.Khan
SUB DIVISIONAL OFFICER Gomal Zam Irrigation Sub Division No.II,
D.I.Khan
EXECUTIVE ENGINEER, Gomal Zam Irrigation Division DIKhan
A-E Services for Monitoring and Milestone Verification of USAID-Funded Waran Canal and Gomal Zam Dam Command Area Development Project in Khyber Pakhtunkhwa
GZIP-Siltation Rapid Assessment Overview Report
November 2017 HPK
Appendix G
Suggested Improvement at Barrage Location
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