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)