Contents 1 Introduction .......................................................................................................................................... 3
2 Community Participation ...................................................................................................................... 3
3 Instituion ............................................................................................................................................... 4
4 Operation .............................................................................................................................................. 4
5 Design and Construction: ...................................................................................................................... 4
6 Headwork .............................................................................................................................................. 5
6.1 Intake Gate .................................................................................................................................... 6
6.2 Sluice Gates ................................................................................................................................... 6
6.3 Weir Body ...................................................................................................................................... 7
6.4 Wing walls ..................................................................................................................................... 7
6.5 Gabion structures.......................................................................................................................... 7
7 Canal...................................................................................................................................................... 7
7.1 Main Canal .................................................................................................................................... 7
7.2 Secondary Canal I .......................................................................................................................... 8
7.3 Secondary Canal II ......................................................................................................................... 8
7.4 Secondary Canal III ........................................................................................................................ 8
7.5 Secondary Canal IV ........................................................................................................................ 8
7.6 Drainage System ........................................................................................................................... 9
8 Other Structures ................................................................................................................................... 9
8.1 Division Box ................................................................................................................................... 9
8.2 Turnout ....................................................................................................................................... 10
8.3 Drop ............................................................................................................................................ 11
8.4 Aqueduct ..................................................................................................................................... 11
8.5 Crossing structures...................................................................................................................... 12
8.6 Level-crossing .............................................................................................................................. 12
9 Watershed of Melka-Hida ................................................................................................................... 14
9.1 Objectives of the Assessment ..................................................................................................... 14
9.2 Methods and Data Collection tools ............................................................................................ 14
9.3 Catchment charcterstics ............................................................................................................. 14
9.3.1 Challenge in the Catchment ................................................................................................ 15
9.4 Water Balance ............................................................................................................................. 16
10 PIDM assessement result of the scheme ........................................................................................ 17
1 Introduction
Melka Hidda SSI scheme is located in Oromia region, Jimma Zone, Gomma district and in three kebeles;
namely Chami Chago, Jimate Daru and Koye Seja. It is situated at 7052’42.55’’ N & 36029’39.98’’ E at 1745
m ASL.. The scheme is acessable on all weather road from district town to the three kebeles which are
not far from the command area; 13 Km from Goma Town (district capital) and 8 km from Jimma-Metu
main road.
The scheme is gravitational diversion weir. According to the feasibility design document the project is
intended to irrigate 57 ha and 137HHs (Revised feasibility report, 2012).
Rapid small scale irrigation scheme disgnosis (RSSISD) is conducted based on the tool prepared by SMIS.
The RSSISD is conducted on Dec 8 and 10/2016. Walk along the main canal and secondary canal,
observation of existing structure and canals status was performed. Discussion with the community, district
IDA and Zone IDA were made.
The project was conceived by the government then Western Oromia Irrigation Development Authority
(WOID). WOIDA office was at Nekemet 200 km from the site, currently East Wollega zonal city. The study
and design of Melka Hidda SSI is conducted in 1997 Eth.C (2003/4). The construction of this project done
in 2007 Eth.C (2013/14) after ten year of the study.
Before the construction, Jimma Zone Irrigation Development office (ZIDA) by the support of private
consultancy firm (Generation Integrated Rural Development Consultancy–GIRDC) sponsored by Embassy
of the Kingdom of the Netherlands (EKN) reviewed the feasibility report and detail design but had not
produced drawings. The only available project drawings during construction was hard copy – tracing paper
(which is not available currently) and blue print drawings.
Beneficiaries participation in both times, study and construction, is very limited near to none.
The diagnoses conducted identifies main technical, social and agronomy problems observed on the
scheme and tries to indicate the main causes of the problem and an input for improvement.
2 Community Participation
The planned beneficiaries of the scheme are 137 (41 in Jimate Deru, 85 chami chengo, and 11 koye seja)
There was very limited participation of the community; discussion on their interest of the project,
committee establishment and petition of agreement were the indicators of the participation. Regardless
of the above limited participation, there was no real consultation about the project, type, route, and other
related issues.
According to the feasibility report, discussion with the community and local administration was
conducted. The report states, both the community and the administration showed positive attitude
toward the project; to develop all the command area and share their land according to the land use
proclamation or their tradition(culture). The document also explains the community agreement not to
demand compensation for the land to be affected by the project. In addition, the study document further
explains the community commitment to contribute labor or cash up to 10% of the project cost.
In reality, their contribution was not significant. Few farmers participated in gabion work around the weir
and individual beneficiaries in their own initiation participated in quality control advising the supervisor.
In general, it can be concluded the community didn’t commit themselves at satisfactory level for the
project implementation.
The beneficiaries are not well organized as IWUA/G. During the feasibility study time a committee was
established but they were not functional.
3 Instituion
Jitu Guddina Irrigation Development Cooperative Society was established in October 2014. Number of
male and female members, size and composition of General Assembly, Management Committee, Control
Committee, Conflict Resolution Committee and any other sub-committees, type and number of employed
staff
Water committee were formed at each kebeles, but they are not fully functional for different reasons
(construction work is not yet finished, poor awareness, less supervision from district…)
4 Operation
The scheme was a traditional irrigation scheme. After the construction, intake point is changed to
downstream (about 100m) and ogee weir with three under sluice and one intake gate to the left
constructed. Due to the nature of the river (full of boulder) the sluice gates are completely broken and
blocked by boulder with more than 1m diameter. This made it difficult for the farmers to operate the
sluice gate. Regarding the intake gate, it is functional and the community operates it.
There is no Operation and Maintenance manual and as built drawing prepared at all level. This is expected
from the contractor during the handover time.
Study and design document is available at region and zone level but not distributed to districts and
IWUA/G. In addition, no contribution for maintenance is done in this scheme, one there is no functional
IWUA/G and no new committee is founded.
Currently the project is at takeover stage, according to the information obtained from ZIDA, from the
contractor (Melese General Water Construction) and transfer to the community via OIDA. There is a
debate on the scheme construction status among the community, the client and the contractor.
5 Design and Construction:
The study and design of Melka Hidda SSI is conducted in 1997 Eth.C (2003/4). The construction of this
project done in 2007 Eth.C (2013/14) after ten year of the study. ‘Fast truck review’ of the project study
and design was done before bid has been floated and construction is supported by Agricultural Growth
Programme (AGP).
6 Headwork
There are two head works in this scheme. The main headwork of the scheme is located at 7052’42.55’’ N
& 36029’39.98’’ E whereas the second headwork of the scheme that is supplementing the scheme is
located at 7052’51.56’’ N & 36031’42.85’’ E.
The main head work was designed to have 0.8m and 24.0 m width but during construction the height is
modified to 1.0 m. The weir consists one intake gate for 49 li/sec flow, three silt gates an average 7.0m
each apart; each one-meter width and one-meter height. The weir u/s part – rectangular section- is
constructed with stone masonry and the d/s face is constructed with concrete. It is provided also with
right and left wing walls. The right bank of the river is provided with additional flood protection-gabion
structure. In addition to this gabion was provided at d/s of the weir for energy dissipation
Photo 1 Head work from right bank perspective Photo 2 Boulder- from U/s to D/S perspective
The second headwork, small regulating structure, weir height 0.7m & width 2.0m is built on small stream
to supply for secondary canal IV. It has one intake gate and two gates over the weir body.
Head Work II -
Supplementary
Head Work I (Main HW)
Intak
The diagnoses result conducted on the main headwork is listed in the following table.
Table 1 Headwork diagnosis
Main Weir (HW-I) Component
Structural Health
Hydraulic condition Descriptions/ advice
Intake gate OK OK Requires lubricating
Silt gate_1 Boulder locked Partially functioning Break & Remove
Silt gate_2 Boulder locked Partially functioning Break & Remove
Silt gate_3 Boulder locked Partially functioning Break & Remove
Weir body OK OK
Right wing wall OK OK
Left wing wall OK OK
Apron Small breakage OK
Gabion at down stream Broken & Washed away
Requires boulder fill like energy block
Gabion- Right side flood protection
OK Partially functioning Reinforcing the gabion
6.1 Intake Gate
The intake gate is functional; Its sheet metal and angle iron frame are functioning well. Small silt which
can be removed by the community is accumulated at the mouth.
6.2 Sluice Gates
There are three sluice gates like barrage gates; one near the intake gate, the second at the center and the
third near the right wing wall. The gates are blocked by boulders transported by the river. The river
morphology shows, the river transports large diameter and heavy boulder. The river morphology needs
detail study and recommendation. Future design guidelines are advised to incorporate river morphology
study under the hydrogeology or geology part which is missing in the feasibility and design document of
this project.
,,
Photo 3 Zoomed in Sluice gates of Melka Hidda SSI Photo 4 Transported Boulder at central silt gate
Figure 1 Head work II- from U/S and D/S persepective
6.3 Weir Body
The weir body is healthy, structurally and hydraulically. Small breakage of the top surface, plastering, due
to boulder rolling on the surface is observed at d/s face and apron of the weir.
6.4 Wing walls
Both wing walls, right and left, are healthy. The left wing wall is expected to be submerged by flood due
to the river bed rise and boulder displacement of the water (right wing wall is not exposed for flood
inundation due to stiff bank along and at the back).
6.5 Gabion structures
Gabion was provided at headwork at two points, at d/s for energy dissipation and at u/s along the left
river bank as an extension for the wing wall, to protect flood escape to the main canal and out of the river
course.
The gabion at d/s is completely damage by transported boulder whereas the gabion at left bank is
deteriorating needs strengthening.
7 Canal
The project has one main canal and three secondary canals (Sc-I, Sc-II Sc-III) from the main headwork
system and only one secondary canal (Sc-V) from the second headwork.
The main canal conveys water from the head work to night storage and also divide to SC-I. SC-II and Sc-III
designed to take water from the pond/night storage.
7.1 Main Canal
The main canal from the headwork to the night storage 2.7 km, a sum of ------- m is lined canal, ------- m
is chute and the rest is earthen trapezoid canal. The shape of this canal is trapezoidal for earthen canal
and rectangular for the lined canal.
0.3m
0.3m
1
1
The lined main canal is broken at some place near the headwork, due to seepage or piping from the cliff
side (left bank of the canal). In addition, almost all of the main canal is silted mainly due to the absence of
cutoff drain, berm and poor community management.
The earthen main canal is damaged by cultivation, silted by the absence of cut off drain, poor management
of the community and weed in the coffee garden. The earthen canal can be said, more than 70% is
damaged. Re-excavation, silt removal and shaping including cutoff drain along the main canal are
obligatory.
Figure 2 Earthen Canal - Trapezoidal shape Figure 3 Lined Canal-Rectangular shape
Figure 4 Broken lined canal and slide earthen canal
7.2 Secondary Canal I
Secondary canal I is branched from the main canal at first division box. It has 234 m of rectangular chute
(0.2m W X 0.2m D) and 366 m trapezoidal earthen canal (0.2m W X 0.2m D, 1:1 side slope).
The chute is structurally and hydraulically healthy, whereas the earthen canal part is fully cultivated and
damaged, even the route is not known. The lined canal is silted with the same reason mentioned above,
absence of cutoff drain, silt and weed.
Awareness for the community, IWUA establishment and strengthen, implementation of bylaw, are the
major solution for the sustainability of canals including this canal.
7.3 Secondary Canal II
This secondary canal is from the night storage to the left side. The earthen canal is fully damaged. Since
the completion of the night storage water has not reached and never filled. This resulted the canal to be
obsolete.
Parallel to the rehabilitation of this canal the main canal has to be rehabilitated and the night storage has
to be tested.
7.4 Secondary Canal III
This canal also intended to get water from the night storage. The total length of the canal is 2.3km, out of
this three consecutive rectangular lined canals 29.0m, 20.0m and -29.0m total 78.0m and the remaining
is trapezoidal earthen canal (0.3m W X 0.3m D, 1:1 side slope).
This canal passes along the wet land which needs additional lined canal to reduce seepage and ground
water table raise in that specific location.
7.5 Secondary Canal IV
This canal directly gets water from the second headwork to irrigate the left side of Melka-Hida river
command area. It commands -----ha. The length of this canal is 600.0 m; out of this 150.0 m is rectangular
lined and the rest trapezoidal earthen canal.
The lined canal is fully covered with weed and filled by silt whereas the earthen canal is damaged by rain-
fed cultivation. Unlike the other beneficiaries, the beneficiaries of this canal are more aware of the
irrigation system. They clean at the beginning of the irrigation season their canal and also excavate the
earthen canal.
7.6 Drainage System
The scheme has no defined drainage system; but the canal system indicates all the canals drains to Melka-
Hida stream.
8 Other Structures
8.1 Division Box
There are two division boxes in the scheme at main canal and Sc-1. Bothe of them except workmanship
limitation structurally and hydraulically are healthy.
8.2 Turnout
Sixty-two turnouts were designed for the scheme but after redesigning it was reduced to 34 but due to
budget limitation only 24 constructed. All turnouts (24), except two of them all are in good condition. Out
of the two one is completely damaged/broken and the other buried under the original ground level. These
two has to be reconstructed checking the design level.
No TO No Canal type
Location Canal bed
F S L Bed of pipe
D/s of pipes
1 TO1 Main canal
0+275 1744.82 1745.035 1745..085 1745.095
2 TO2 0+375 1744.45 1744.665 1744.715 1744.825
3 TO3 0+730 1730.38 1730.595 1730.645 1730.835
4 TO4 0+785 1730.265 1730.52 1730.57 1730.58
5 TO5 0+975 1728.766 1728.989 1729.039 1729.049
6 TO6 0+1050 1728.124 1728.339 1728.089 1728.059
7 TO7 0+1283 1718.734 1718.949 1718.999 1719.009
8 TO8 0+1350 1718.6 1718.815 1718.865 1718.875
9 TO9 0+1547 1704.476 1704.691 1704.741 1704.885
10 TO10 0+1734 1703.002 1703.217 1703.267 1703.277
11 TO11 0+2014 1697.945 1698.16 1698.21 1698.22
12 TO12 0+2055 1697.783 1697.998 1698.048 1698.058
13 TO13 Sec-3 0+2219 1691.837 1692.06 1692.11 1692.12
14 TO14 Sec-3 0+2429 1690.65 1690.865 1690.915 1690.925
15 TO15 Sec-3 0+2579 1690.35 1690.565 1690.615 1690.625
16 TO16 Sec-3 0+825 1672.58 1672.795 1672.845 1672.855
17 to17 Sec-3 0+925 1672.38 1672.595 1672.645 1672.655
18 TO18 Sec-3 0+1050 1672.13 1672.345 1672.395 1672405
19 TO19 Sec-3 0+1225 1671.88 1672.095 1672.145 1672.155
20 TO20 Sec-3 0+1327 1671.676 1671.891 1671.941 1671.951
21 TO21 Sec-3 0+1402 1671.526 1671.741 1671.791 1671.801
22 TO22 Sec-3 0+1477 1671.376 1671.591 1671.641 1671.651
23 TO23 Sec-3 0+1522 1671.226 1671.441 1671.491 1671.501
24 TO1-1 Sc1 0+110 1735.358 1735.468 1735.398
8.3 Drop
Eighteen (18) drops were designed whereas seventeen drops (17) constructed, the remaining one is not
required. All the drops are functional; silt, weed and poor management are the warning sign for structures
life.
No Drop No
Canal type
Location
Drop height
OGL U/S D/S
1 D-1 MC 0+499 1.6 1740.4 1739.3 1737.7
2 I-D-2 MC 0+888 1.15 1730.536 1730.106 1728.956
3 D-3 MC 0+1005 0.5 1729.106 1728.706 1728.206
4 D-4 MC 0+1063 0.5 1728.498 1728.098 1727.598
5 D-5 MC 0+1150 1 1720.4 1720 1719
6 D-6 MC 0+1356 0.4 1719.988 1718.588 1718.188
7 D-7 MC 0+1391 0.5 1718.518 1718.118 1717.618
8 D-8 MC 0+1391 12.618 1718.518 1718.118 1705.5
9 D-9 MC 0+1400
10 D-10 MC 0+1424 0.6 1705.852 1705.452 1704.852
11 D-11 MC 0+1549 0.43 1704.802 1704.402 1703.972
12 D-12 MC 0+1886 0.708 1703.098 1702.708 1702
13 D-13 MC 0+2304 0.791 1692.091 1691.691 1690.9
14 Sc1-D-1 Sc1 0+100 0.5 1736.078 1735.878 1735.378
15 Sc1-D-2 Sc1 0+115 0.4 1735.738 1735.338 1734.938
16 Sc2-D-1 Sc2 0+58 1.5 1684.689 1688.524 1687.024
17 Sc4-D-1 Sc4 0+75 1 1679.34 1678.94 1677.94
8.4 Aqueduct
Two (2) aqueduct was designed but four (4) constructed. Two big aqueducts are on the main the rest on
secondary canal 3 to cross streams. All of them are structurally sound. All of them are RCC. The second
aqueduct at the main canal is covered with weeds, it needs clearing and proper management.
Description Location
Dimension
Length (m)
Width (m) Depth (m)
Aquidct-1 Main Canal 20
Aquidct-2 Main Canal 20
Aquidct-3 Secondary-3 3
Aquidct-4 Secondary -3 3
Figure 5 Aqueduct II at MC
8.5 Crossing structures
Sixteen (16) crossing structures designed and only eleven (11) crossing structures constructed due to
budget limitation. According to this diagnosis additional 5-6 crossing are important. The first culvert is
filled with silt and doesn’t function fully. It has to be demolished and reconstructed with proper slope and
size. The other culverts except silt clearing, structurally they look fine, but for the hydraulics they have to
be checked after the main canal rectification.
8.6 Level-crossing
There is only one level crossing, all of its gates are functioning and structurally and hydraulically looks
comprehensive.
Scheme is not functioning fully
No Proper Irrigation User
Institution Structures do not
function fully
Part of lined canal
broken
Some Farm
structures are
broken &
burried
No Sound
Participatory
approach during
study
Earthen canal is
cultivated,
damaged &
silted
No significant discussion
and meeting with
beneficiaries during &
after construction
Water is not reaching fully to
the scheme
No responsible body for Irrigation
facility operation & maintenance at
scheme level
No Irrigation water
management
Only Small area is
under irrigation
pump & traditional
diversions irrigation is
taking place
No proper water
scheduling Constructed & excavated
facilities are damaged
Seepage at Earthen
canal
Problem
Cause
Effect
Irrigation Development Cooperative established only by
some beneficiaries (at one kebele), even not functioning
9 Watershed of Melka-Hida
9.1 Objectives of the Assessment
The main objective of this watershed diagnoses is to understand the impact of the watershed charctesrtics
on the scheme sustainability, especially on the headwork and downstream.
The watershed of Melka-Hida SSI is dignonsised because of the special nature of the river and its impact
on the scheme. As it is explained in the engineering part boulders with different diameter are bombarding
the headwork always during flood time. This resulted blocking the silt gates and made them
nonfunctional.
This diagnostics tries to shows the watershed chartcerstics of the scheme and the need for river
morphology assessement during the detail study & design of the scheme.
9.2 Methods and Data Collection tools
Checklist for data collection & field observation developed, discussion with district experts, Da and
community conducted, maps, satellite data and other supporting information consulted.
9.3 Catchment charcterstics
The cathment area is nearly 36km2 (3656ha). The longest mainstream/drainage length 9.2km. The slope
of the catchment rainge from 0-15%.
Slope range (%) Area (km2) Remark
0-5 35
5 -1 0 9.2
>15 0.49
Figure 6 Melka-Hida drainage net work and elevation difference
The watershed is divided in two relatively big sub watersheds, Daru Mujie & Odo. Further Daru Muje sub
watershed is divided into two small sub watersheds called Daru & Muje. Odo is divided into four small sub
watersheds (Gole SWS, Keja SWS, Limit SWS, & Darare SWS).
The land cover of the catchment, in general, can be said vegetative., Farm/home stead, Forest, coffee
land and shirubs dominate the catachment.
Table 2 Land use of the Basin
Description_land use
Coverage_area % by Data source
Hydrology report of the study
Watershed report of the study
OSMIS- Observation Remark
Forest/cofee 32 75 21.4/30 Dominant around headwork
Grass land 13 2 2.1/5
Farm/home stead 55 22 76.5/64 U/S of the catachment
Others 1 1
Figure 7 Land use and longitudinal profile of Melka-Hida
The forest in the catchment is releatedd to coffee. The land use contributes to erosion because of non
controlled farming like hillside farming, farming across/perpendicular to the counter and others.
9.3.1 Challenge in the Catchment The most significant challenge in this scheme releated to the catchment is boulder transportation,
affecting the diversion weir and it’s facilities. As described in the engineering section; boulders are
clogging and breaking the gates, the weirs, gabions and dykes.
The feasibility study, Watershed and hydrology, didn’t identify the boulders and its root cause. This
diagnoses brought the boulder issue as the most significant. According google earth pro image, it looks
the boulders are evolving from somewhere around 5km far from the headwork, which has 10% in 400m
span.
Figure 8 Potential boulder source
9.4 Water Balance
Melka-Hida is the tribuitory Dhedessa river that is the main tribuitory for Abay. Melka-Hida is not gauged
river. The river has no U/S and D/S irrigation users. This made the water balance issue simple, just only
considering this catchment.
The dry time flow of the river according to the design document and as verified in our field trip is about
45li/sec. Without going in detail analyises the water balance, the river yields 3888m3/day and 816,480
m3/year (considering only seven months of the year that can be used for irrigation). Taking 1.5 li/sec/ha
as average duty for the area, the available water, considering 25% down stream release, can irrigate about
59 ha per seasoon.
The project is currently designed for 57ha. Expansion of area or new irrigation without introducing water
saving technology whether at U/S or D/s risks the project.
10 PIDM assessement result of the scheme
Assessment Phase Existing Activities and Procedures
Step 1 Registration of Application for SSI Scheme Development
First SSIS development idea was government plan, 2002
In 2012 community raise its demand verbally to District concerned offices
Approved/given priority for tendering
Step 2 Pre-Feasibility Studies
Both pre-feasibility and feasibility were conducted in 2002 OIDA*
This study document was revised in 2012 by the consultant
Step 3 Community Awareness Campaign
In both cause community was aware of SSIDS
The awareness was given by Regional and Zonal experts
Community’s obligation in the construction process, Scheme operation and maintenance responsibilities after the handover took place, the need for contribution of irrigation service fee were the main topic of discussion.
Water user committee with 7 members (all Male) was established at this stage
Step 4 Feasibility Studies Mentioned on step 3
Step 5 Preparation and Approval of Feasibility Report (Milestone 1)
The fusibility report (for the revised document) was: Prepared by: Generation Integrated Rural Development Consultant (GIRDC), 2012 ; Approved by: OIDA and Signed between: OIDA and Generation Integrated Rural Development Consultant (GIRDC).
Preparatory Phase Existing Activities and Procedures
Step 6 Participatory Scheme Design
Was not participatory
Step 7 Establishment of WUGs and IC/IWUA (if required)
This SSIS gives service for 3 Kebeles
Some farmers only from two kebeles became IC member
IC get registered
From 100 IC members (75 Male and 25 Female), 40 of them (all male) do not have irrigable land
Step 8 Preparation of Agriculture Development Plan
ADP was not practicing on this scheme
Step 9 Preparation of IC/IWUA Capacity Development Plan
No
Step 10 Preparation of Soil and Water Conservation Plan
No
Step 11 Preparation and Signing of Scheme Development Agreement (Milestone 2)
Not yet
Implementation Phase Existing Activities and Procedures
Step 12 Land Acquisition and Allocation
Did not took place (no need)
Step 13 Tender and Execution of Construction Works
tender process was handled by OIDA, and signed with the bidder in Addis,
The construction was conducted by the bid winner and the supervision activity was conducted both by OIDA and Jimma Zone Irrigation Development Authority Office.
Step 14 IC/IWUA Capacity Development in Governance, Administrative and Financial Management
No
Step 15 Execution of Agriculture Development Plan
No
Step 16 Execution of Soil and Water Conservation Plan
No
Step 17 Capacity Development of IC/IWUA and WUGs in O&M and Water Management
No
Step 18 Preparation and Signing of IMT Agreement (Milestone 3)
Not yet
Operation and Maintenance Phase
Existing Activities and Procedures
Step 19 IC/IWUA-Managed Operation and Maintenance of SSI Scheme
Not conducted
Step 20 Monitoring and Evaluation of IC/IWUA Performance
Not conducted
Step 21 Monitoring and Evaluation of Environmental, Socio- and Agro-Economic Impact
Not conducted
*First OIDA which was functioning (2000-2008)