Report No: R-39.4

PILOT PROJECT FOR FARMER-MANAGED IRRIGATED AGRICULTURE UNDER THE LEFT BANK OUTFALL DRAIN, STAGE-I

PROJECT

MONITORING AND EVALUATION OF IRRIGATION AND DRAINAGE FACILITIES

FOR PILOT DISTRIBUTARIES IN SINDH PROVINCE, PAKISTAN

Voluinc Four IIeran Distributary, Sangliar District

Interim Report

1) y

Ui I<. 1,ashari M. Navccd Kliayal Niaz Hussain Sial

Abdul Majeed Ansari Abdul Jalil Ursaiii

Gliulam Shabir Soomro M. Ghous Lagliari M. Akhtar Bliatti

M. S. Shafique Caylord V. Skogerboe

December 1997 IIY DICKABAD OFFICE

PAKISTAN NATIONAL PROGRAM INTERNATIONAI, IRRIGATION MANAGEMENT INSTITUTE

TABLES 01' CONTENTS

TABLE OF CON'I'ENI'S ............................................................................................................................................. i

LIST OF TABLES AND FICtJRES ....................... .....: ............................................................................................ i i

... ACKNOWLEDGMENTS .......................................................................................................................................... 111

... 1 . IN'rHODUC 1 ION ............................................................................................................................................. 1

1 .1 B A C K W O U N D ............................................................................................................................................ I 1.2 PURPOSE ...................................................... ........................................................................................... 1 1.3 ACCOMI'LISIIMIIN'I' IN I I I R A N UIS'fRI 'AKY COMMAND AREA I I .4 MONITORING AND LiVAl-lJATION 01: IIERAN DISTRIDUTARY ........................................................ 2

DESCRlP'I'ION OF HEKAN ~ ~ ~ t ' ~ W W ~ ' A ~ Y ............................................................................................ 3

................................................

2.

2.1 LOCATION ............................................................................................................................. 2.2 S A I ~ l l N r I'IIYSICAl, F 1 ~ A T ~ J K 1 3 ....................................................................................... 2.3 CLIMA'J'E ....................................................................................................................................................... 3 2.4 IRRIGA'I'ION SYSTEM .......................................... ............................................................................... 3 2.5 DRAINAGE SYSTEM .................................................................................................................................. 7 2.6 LAND USIi ......... .................................................................................. 2.7 CXOI'S ................ ................ ................................................................................................... 8 2.8 GROUNDWATER ................................................................................... ............................................ x 2.0 I1UW.i A'l'lON PRA\C"I'IC'ES ..................................................................... ............................................. 0

KESUL'I'S AND DISCtJSSION ...................................................................................................................... 10

IRKIGA'fION DELIVL:.RY S Y S m v l .......................................................................................................... 10 3. I . I O~icrvi~ions oflt.rig(iiiorr Dcliwty Sjwcrrt.. ............................................................. 10

3.1. I .2 Irrigation Supplics at Watcrcoursc Outlcts .................................................... 13

3.

3.1 .................

3. I . I . I

3 . I . I .3

IrrigJtion Supplics at Ilcud Rcgulator of thc llcran Distributary ........................................... ..................

1:luctuations in Watcrcoursc Supplics

3.1.2 tWiirrtcwrrrcc of Ii.r.igr 3. 1.2. I Gcwc*rtrl M t r i r i i c w r r ~ c v ,. , . , ,_. , , ..........................................

3.1.2.2 Physical Cotitlilions. .......................................................... DKAINflGI~ DISPOSAL S Y s - n i M ( D W .................................................................................................. 3x

3.2. I ~ ~ / J l ' l ' f l f f f ~ ~ l . S O ~ / ~ l Y l ~ l l t l ~ f ~ ~ ~ l ~ . ~ / t ' l l l ..................... .j 9 3.2.1.1 l ) r a i w c EnlusnI ................................................................ 3.2.1.2 WIICI *r;lblr i w i 1 ............................................. 3.2. I .3 ( i twmiwaw Vualits. ......................................

3.2 .....................................

............................................. ...............................................

3.2.2 Altriritcwtrrtcv 01 /hiituig(> .Syst~w~ ........................................ ........................ 4 CON c 1- I<) NS .............................................................................................................................................. 4 5

1. .- Kit: LHE N C ............................................................................................... .~. ....................................................... .4 S

ANNEXES

A"lX A DlSCll ARGI: Ml%SUREM1iNTS .......................................................................................................... 46 A"I:.X 13 PII ' .mMITER 1)A'I-A ............................................................................................................................. 00

I

LIST OF 'TABLES AND FIGURES

.. I able 2.1 . Saliellt features oftllc 1 leran Distributary; Sanghar ..................................................................................... 6 Tahlc 2.2. Salicnt fcatures of thc Kliadwari Minor (Hcran Distributary). Sanghar ....................................................... 6 Table 2.3. Salient features of surfacc drains in thc Ilcran Distributary command a m , Sanglinr .................................. 7 Tablc 2.4. Salient fcatures of tubewells in thc Hcran Distributary command area ...................................................... 8 'rablc 3 . I Types of outlets and their operating condition (Iicran Distributary) ......................................................... 13 'rablc 3.2 Typcs of outlets and their operating condition (Khadwari Minor) ........................ ..................................... 14 Table 3.3. Coefficient of temporal variation for day and night dischargc mcasurenicnts of I lcriii

Distributary. Sanghar ................................................................................................................................. 21 Table 3.4. Coefficicnt of temporal variation on an hourly basis for dischargc nicasiircnicnts of I lcraii

Distributary, Sangliar ................................................................................................................................. 36 Table 3.5. Performance sununary of Irrigation Delivery System of the Heran Distributary, Sanghar ........................ 36 Tablc 3.6 Vegetative growth and weak-portion survey of the Heran Distributary and Khadwnri Minor,

Sangliar ...................................................................................................................................................... 38 Table 3.7. Contribution of the surface drains in 1 lcran Distributary Command Area, Sanghar ............................. 39 Table 3.8. Water quality in the llcran Distributary Comniand Arca. Sanghar ............................................................ 43 Tahle 3.9. Vegctative growth and weak-portion siirvcy of surfacc drains in the Heran Distributary

C o n i n m J h a . Sawllar ........................................................................................................................... 44

FIGURES

Figure 2.1. Location map of thc llircc pilot distributarics in Sindh Province .............................................................. 4 Figiirc 2.2. Layolit plan of tlic 1 lcrali Distributary command area .............................................................................. 5 Figure 3.1. Monthly avcragc discliargc entering Heran Distributary for Kliarif 1997 .............................................. 11 Figwe 3.2. Tcmporal Coefficicnt of Variability at head regulator of thc Ileran Distriburtary for Kharif 1997 ....... 12 Figure 3.3. Normalizctl watcr tliscliargc of outlcts from I leran Distributary for April 1997 .................................... 15 Figure 3.4. Normalized water discharge of outlets froni Heran Distributary for May 1997 ..................................... 16 Figurc 3.5. Nornializcd water discharge of outlcts from-heran Distributary for June I997 ...................................... 17 Figure 3.6. Normalized water discharge of outlets froni Heran Distributary for July 1997 ...................................... 18 Figure 3.7. Nornialized water discharge of outlets from Heran Distributary for Aug 1997 ..................................... 19 Figure 3.8. Nornialized water discharge of outlets from Heran Distributary for Sept 1997 ..................................... 20

Figure 3.11. Discharge of Heran Distributary and some sample outlets (Aug 18/19. 1997) ...................................... 24

.

Figure 3.9. Spatial Coefficient of Variability aniong the outlets from Heran Distributary Kharif 1997 ................... 22 Figurc 3.10. Temporal Coefficient of Variability at outlets from the IIeran Distributary for Kharif 1997 ................ 23

Figure 3.12. Discharge of Heran Distributary and its sample outlets (August 19/20. 1997) ...................................... 25 Figure 3.13. Discharge of Heran Distributary and its sample outlets (August 20121 1997) ....................................... 20 Figure 3.14. Discharge of Heran Distributary and its sample outlets (August 21/22. 1997) ...................................... 27 Figurc 3.15. Discharge of tlcraii Distributary and its sample outlcts (August 22/23. 1997) ..................................... 28 Figurc 3.16. Dischargc of Heran Distributary and its sample outlets (August 23/24 . 1997) ...................................... 29 Figurc 3.17. Discliargc of Khadwari Minor and some sample outlet (18119 August 1997) ........................................ 30 Figurc 3.18. Discliargc of Khadwari Minor and somc saniplc outlcl(I9/20 August 1997) ........................................ 31 Figure 3.19. Discharge of Khadwari Minor and some sample outlet (20121 August 1997) ........................................ 32

Figure 3.2 1 . Discharge of Khadwari Minor and some sample outlet (22123 August 1997) ........................................ 34 Figure 3.22. Discharge of Khadwari Minor and some sample outlet (23124 August 1997) ........................................ 35 Figure 3.23 Average watcrtablc dcpth in Ilcran Distributary Command Area for ..................................................... 41 Figurc 3.24. Piezomctcr locatiw and avcragc watcrtablc dcpth for Kliarif 1997 ....................................................... 42

Figurc 3.20. Discharge of Kliidwari Minor and somc sample outlet (21122 August 1997) .................................. .. ..... 33

ii

ACKNOWLEDGMENTS

Tlic authors of this rcport exprcss their profound thanks to thc Projcct Lcadcr, Mr. D.J. Bandaragoda, Scnior Management Specialist, for his guidance and encouragcnicnt in utidcrtaking most of thc nctivitics rcportcd hcrc. Wc also convcy our gratitudc to Dr. Yamccn Memon, Teani Leader and Sociologist, for his support in conducting thcse activities. Thanks arc due to Mr. Abdul Hakccin Khan, Mi. Nisar Hussain Bukhari and Miss Rubina Siddiqui who helped in calibrating thc outlet structurcs and mcasuring flows.

Special thanks arc due to Mr. M. Wasi Shcikh, Mr. Alisan Ali Kazi, Mr. Ayaz Anwar Solangi and Mr. Faisal Mcmon for assisting in several ways during report prcparation in thc Hyderabad Officc of IIMI Pakistan.

Also, we are ,very gratcful to Mr. Manzoor Hussain for his cfforts in formatting and compiling this report.

iii

1. INTRODUCTION

1.1 BACKGROUND

Tlic International Irrigation Managcnicnt lnstitutc (IIMI) is iiiiplcmcnting tlircc pilot projccts on Faniicr-Managcd Irrigated Agriculturc since July 1995, in collaboration with tlic Agricultural Engincering atid Watcr Managcincnt Dircctoratc of tlic Dcpartnicnt of Agriculturc, Covcrnnicnt of Sindli. Tlic tlirce pilot projects sclectcd from tlic LI30D projcct arca, onc from each of tlie tlirce districts of Nawabsliah, Sangliar and Mirpurklias, arc to assist fariiicrs in undcrtaking Opcration and Maintenancc (O&M) of thc combined irrigation and drainagc facilities. This would bc acliicved through assisting faniicrs to organizc thcmsclvcs into Watcr Uscrs Associations (WUAs) at tlic watercoursc level and into Watcr Uscrs Fcdcration (WUF) at tlic distributary Icvcl. Tlic expericncc gaincd from these pilot command arcas would also Iiclp in idcntifying and dcveloping an appropriate institutional process, along with lcgal requircnicnts, for effective iniplcineiitation on a broadcr scalc for all of thc distributarics in a CiItIal comnianti nrca.

1.2 PURPOSE

The purpose uiidcrlying tliesc pilot projccts is that the WUAs and WUFs woultl evcntually bc accountable for thc water reccivcd at the hei~d of tlic distributary, rcsponsiblc for watcr distribution among tlic niciiibcrs, collcction of watcr charges, along with opcration and iiiaintcnancc (OSLM) of tlic coiiibiiicd irrigatioii and drainagc Tacilitics in thcir distributary command arca. TIicy niay also adopt rcviscd proccdurcs on watcr allocation, distributioii, watcr charges asscssniciit and collcction with the agrecmcnl of tlicir niembcrs. WUFs would bc cxpcctcd to cntcr into agrcenicnts with their own members and the Sindh Irrigation and Draiuagc Authority (SIDA) for iniplemcntation of tlie proposed activities. The broad piirposc of tlicsc pilot projects is two fold:

(i) to test tlic viability of farnicrs' managing parts of irrigation systems, niorc spccifi'cally distributarylminor canals, so that more cfficicnt aiid cqiiitablc distribution of water can be achieved; and to make rccommeiidations related to futurc extcnsioiis on tlic basis of rcsults from t hc pi lot projcc t s

(ii)

1.3 ACCOMPLISIIMENT IN IlERAN DISTRIBUTARY COMMAND AHISA

Tlie Hcran Distributary command area, Sangliar District, is oiic of tlic tliree pilot projccts. Coiisidcrablc progrcss lias bccn iiiadc i i i thc iniplcnicntation of projcct activitics at this sitc. Tlic project staff lias assistcd farmers to organizc tlicmsclvcs into Watcr Uscrs Organizations (WUAs) in iill of tlic 31 watcrcoursc coniniands. Using tlic WUAs as basic organizations, a Watcr Uscrs

1

Fcdcration (WUF) has bccii fornicd at thc distributary Icvcl. At prcscnt, a Joint Managcmcnt Agrccmciit (JMA) is being ncgotiatcd bctwccn thc Sindh Irrigation & Droiiiagc Authority (SIDA) and the Heran WUF. According to this agreenicnt, thc Hcraii WUF would undcrtakc opcration of tlic combinccl irrigation and drainagc facilitics including cotlcction of watcr chargcs, improving watcr nianagcnicnt and drainagc practiccs, and carry out othcr rclatcd activitics, including tlic niaintcnancc of irrigation and drainagc facilitics in tlic IIcraii Distributary command arca.

Thc main purposc of this cfrort is thc involvcnicnt of fanncrs in opcration and niaintcnancc of thc conibincd irrigalion and drainagc systcms, which has ncvcr bccn succcssfully accomplishcd beforc in tlic country. Thcrefore, there is a strong nccd and justification for monitoring tlic proccss cmploycd and its impact towards acliicving thc objcctivcs.

1.4 MONITORING AND EVALUATION OF IiERAN DISTRIBUTARY

(i) allow tlic SIDA and WUFs to adjust thcir activitics to thc nccds and cotistrains of the irrigation and drainage management turnover projects; and

(ii) provide policy-makers and planners with up-to-datc iiiforniation about thc consequences of appropriate nianagenient changes for planning ncw projccts that could bc cxtcnded to othcr distributary command areas.

As a first stcp, Monitoring and Evaluation (MScC) of the irrigation dclivcry and drainagc disposal systcms was undcrtakcn to documcnt thc on-going situation bcforc tlic nianagcnicnt turnover of thc Hcran Distributary coininand 'arca to the WUF. A dctailcd nicthodology was dcveloped for data collection and analysis. Actual ficld data collcctioii was starkd in April 1997. This is an intcriiii report that suniniarizcs tlic results and findings of tlic M&E activitics undertaken so Far.

2

2. DESCRIPTION OF IIERAN DISTRIBUTARY

2.1 LOCATION

The Hcran Distributary takcs off from tlic right bank of Nara Canal at KD 129, thcn flows from East to Wcst from thc Nara Canal. The command area is situated to the north of Sanghar City. Tlic road from Sangliar to Gujri crosses the Heran Distributary at RD 11. Thc tail of thc distributary lies in between Chak No. 9 and Chak No. 11. The Heran Distributary also has a minor known as Khadwari Minor. Thc Khadwari Minor takcs off from tlic lcft bank of thc l-icran Distributary at RD 10 and flows from North to South (parallcl) to thc Sangar-Gujri Road, whereas the tail is near Chak No. 10. A location map of the project area is shown in Figure 2.1 and a command map of thc distributary is presented in Figure 2.2.

2.2 SALIENT PHYSICAL FEATURES

The head regulator consists of three gates. Two of them are closed and thc middle one is fLtnctional. Tlic cross ,rcg:ulator i l t RD 10 is dysfunctional. Thc distributary channcl has a turn of about 65 dcgrcc at KD 19. l’hc inspcction path is in good condition. l’hc distributary has onc minor called Khadwari Minor which offtakcs from it at RD 10. Thc hcad rcgulator of thc minor is functional. Thc salient fcaturcs of the Hcran Distributaty are shown i n Table 2.1.

2.3 CLIMATE

The cliiiiatc is arid sub-tropical with vcry hot suninicrs and niild wintcrs. Thc mean daily maximum tenipcratures in suninicr rangcs from 39°C to 41°C and the mean monthly maximum tcmpcrature is about 43°C to 45°C. I n wintcr, .the mean daily minimum temperature is about 7°C with tlic incan monthly inininium tcmpcraturc falling to 2.5”C. The m a n monthly sitmnicr rainfall varies from 32 nim in thc North to 46 inn1 in the South. Thc wintcr is practically rainless. I n gcneral, the cliniatc is typically dcsert typc with very hot days in thc summer and cold nights in wintcr with frost and fog frcquently appcaring. Dust stornis arc coninion during thc sumnicr.

2.4 IRRIGATION SYSTEM

Thc climax in thc devclopmcnt of thc canal irrigation system in Sindh was achicvcd i n 1932 whcn tlic Sukkur Barragc, thc lilrgcst canal irrigation systcm in thc world, was commissioncd. Thc Sukkur Barragc provcd to bc a grcat succcss. The Nara canal command arca has a gravilatiotial systcni (canal walcr). This systcm consists of niain canals, branch canals, distributarics atid minors. Tlic 1-Icran Distributary offtakes from thc Nara Canal. Thc Nara Canal is part of an old rivcr, which was an inundation canal with its soitrcc of supply from tlic foot of thc Putijab hills.

3

Figute2.1. Location map of the three pi lot distributaries in Sindh Province.

4

W

9

a

4. 0 x

2 W bi a OD

Lrc ..I

N 5

Tablc 2.1. Salicnt fcaturcs of thc 14craii Distributary, Sangliar.

Dcscription

Lcngth

Old dcsign discharge

Old dcsign dcpth at tlic licad

Old design dcpth at thc tail

Nunibcr of outlcts

~ ~-

Detail

1O.G kin

58.0 cfs

2.6 rcct

1.1 fcct

24

Lined watercourscs

APM outlcts

Tlic salicnt fcaturcs of tlic minor arc givcn in 'I'ablc 2.2.

23

20

Tablc 2.2. Saliciit fcaturcs of tlic Kliadwari Minor (Hcran Distributary), Sangliar.

II Dcscri p tion I Dctail

Lcngtli of minor 5.12 kin

Old dcsign discliargc 10.62 cfs

Nunibcr of outlcts 7

Liiicd watcrcoiirscs 4

Unlincd watcrcourses 3

11 Culturcable Command Arca (CCA) I 3,065 Acrcs

Tlic Sukkur Bairagc scrvcs to inaintain watcr lcvcls i n thc liidus Kivcr in ordcr to pcmiit adcquatc irrigation flows to bc divcrtcd inlo a total of SCVCI~ canals ofnaking on both sidcs of thc Borragc. Tlic Nara Canal is thc largcst offtaking canal of llic Sukkur Barrage. Nara Canal is irrigating tlircc districts: Sangliar, Mirpurklias and Thurparkar. Thc tieran Distributary was constructcd during the construction period of Sukkur Barragc. Prior to its construction, most of tlic ilrcil was bnrrcn land. Wlicii thc British Govcrniiiciit distributcd tlic land of this arca to tlic Ex-Amy pcoplc, then cultivation startcd.

G

Application of irrigation watcr li-oni tlic Ilcran Distributary to tlic Fi~riii ficlcls is through w i i t c ~ c o ~ i ~ ~ c ~ which arc coiitrollccl by outlets (moglias). Within a watcrcoursc c~niiiiaiiel ;ircii, which is ranging from 200 to 700 acres in s i x , tlic sliarcholdcrs receivc a supply of watcr proportional to tlicir land Iiolding s i x . 'Tliis is acconiplislicd by assiining tlic cntirc flow of thc watcrcoursc, usually bctwccii oiic and tlircc cusccs, to onc farn1 for a spccificd tinic pcriod on iI scvcn-day rotation. Tlic rotation sclicdulc, callcd tlic warabantli, was cstablishcd by tlic Irrigation Dcpartmciit, i f not mutually agrccd by tlic fiirnicrs.

Nanic of drain

MBD

M-IRA

M - I R

s- 1 R

2.5 DRAINAGE SYSTEM

discliargc ('") Total Icngtli (km) Lciigtli in conimand arca (km)

96.6 20.73 9.75

17.60 7.10 3.70

79.50 23.29 3.00

43.00 I 1.30 11.21

Land is said to be watcrloggcd when its productivity or fcrtility is affcctcd by liigli watcr tablc. Tlic ~ ~ V C ~ S C cffccts of high watcr tablc lipoli tlic yicld of crops also dcpciitls up011 thc natiirc of tlic crop grown. If tlic watcr tablc is in a statc of cquilibriuiii naturally, tlic aiiiouiit or inflow is practically cqual to tlic amount of outflow. This cquilibriiiiii is iipsct by tlic liugc flow of watcr in thc Niiril Ciillill : i i d construction of iicw brriiicli CiiIiiilS, wliicli contrihutctl to tlic \viltcr tablc through sccpagc and tlccp pcrcolation. I-Icncc, tlie watcr tablc has riscii to a significant Icvcl. Iii Ilic pilot conimand arca, tlic LBOD spread a nctwork of surfacc drains anel saliiic anel scavcngcr tubcwclls, but Ilic luhcwclls ilrc still unclcr thc proccss of installation. 'I'lic following arc tlic conipoiicnts of tlic scliciiic to conibat tlic problciii of watcrlogging and salinity in Ilic arca:

A iictwork of surfacc drains discharging to tlie sca via a spinal drain and t iclal link.

- Deep tubcwclls to intcrccpt sccpagc watcr and coiitrol tlic ground watcr tablc by

Special wclls to scavcngc ficsli wntcr lciiscs Tor usc in irrigation.Buricd intcrccptor

On-Fmii watcr Iiiiilii1~Ci1iciit to improvc watcrcourscs and watcr usc IJrilct iccs.

puiiipiiig ground watcr into the surface drainagc nctwork.

elrains bcsidc ciiiials to rccovcr tcsli watcr sccpagc for iisc in irrigation. -

-

Tlic tlrains which covcr thc I-lcraii Distributary command arca arc givcn bclow.

Tlic subdrain M- 1 RA discliargcs into tlic branch elrain M- 1 K and this branch drain dischargcs into MUD. Tlic MUD cntcrs inlo Sangliar Main Drain, wliilc S-1 R dircctly disposcs

7

into Sanghar Main Drain. Undcr thc LBOD projcct, thc salinc and scavcngcr tubcwclls arc bcing installcd and linkcd with thcsc subdrains and branch drains for tlic purposc or disposal. I’hcir dctail is prcsciitcd in Tablc 2.4.

MBD

Tablc 2.4. Salient featurcs of tubcwclls in the Hcran Distributary coniniand area.

Draiiiagc 07 2.0

~ ~~ ~~

Nanic of drain 1 Typc of tubcwcll- 1 Nuniicr ~~~ 1 Capacity (cfs)

M-IRA

S-1 R

Sc;ivangcr 02 2.0

Scavangcr 17 2.0

M-IR I Driiinagc I 2.0

S-IR I Drainngc 108 I 2.0

2.6 LANDUSE

Most of this area compriscs arable irrigatcd land, with small patches of unuscd land that has becomc saline and alkalinc. TIicrc arc distinct cropping pattcrns that cmcrgc in accordaiicc with the varying availability of water.

lrrigatcd agriculturc is thc pi-cdominant land usc of tlic arca. Mostly, soils arc loamy and sandy loam soil. About 85% of thc land is uscd for growing crops, 3% of tlic land is uscd for gardcns, whilc 12% of thc land is not uscd for any purposc iiiid rcmains fallow laiitl.

2.7 CROPS

The climatic coiiditioiis and soil structure both arc favorable for cultivating diffcrcnt crops. The major crops in the distributary coiiiniand area arc cotton, whcat, sugarcanc, oil sccd, berseem, maizc, vegetables, ricc and groundnuts.

2.8 GROUNDWATER

In tlic command wc;i of tIic I Icriin Distributary, thc canal watcr is bcing usctl for Thc ground watcr had bccn cxploitcd but not found fit for irrigation

Ncvcrthclcss, tlic canal watcr is availablc i n sufficicnt quantity and thcrcforc, irrigation purposcs. purposcs. groundwatcr is not in dcniand.

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2.9 I KR1 C AT1 O N I'HAC'I'I C ES

Eficicnt nianagcnieiit of irrigation water is important for boosting tlic agricultural ccononiy. Tlic propcr application of irrigation watcr plays an important rolc in watcr savings and iiicrcasing agricultural productivity. 'I'lic Hcran Distributary command srca is mostly bcing irrigated by tlic basin irrigation mcthod, which lias traditionally bccn in existcnce sincc thc fiuictioning of tlic distributary. This nictliod is bcing uscd for all crops, cxccpt vcgctables.

At prcscnt, thc cotton crop is bcing cultivatctl on ridgcs (Currow iiicthocl), with this prnclicc bciiig inilialccl diiriiig the lust two or tlircc ycars. Tlic iiiuin rciisoii for colton crop cultivntioii oii ridgcs / fiirrows is to avoid salinity atid watcrlogging problcms.

Lift irrigation for cultivation of crops wiis iiot sccn in tlic arca. t Iowcvcr, it lias bccn rcliably dctcniiincd that sonic fiiniicrs usc lin irrigation to fctch watcr from drains during thc pcriods of watcr shortage.

3. HESULTS AND DlSCUSSION

Tlic rcsults of the iiionitoring and evaluation activitics untlcrtakcii i n tlic I Icran Distributary command arca sincc April 1907 arc discussed bclow. The focus was 011 captiiring thc on-going coiiditions and practiccs (pliasc I of ilic moilitorin!: and evaluation proccss) which rcprcscnts thc status of '%cforc" thc irrigatioii nianagcmcnt turnovcr.

3.1 IRRIGATION I)EI,IVE:HY SYSTEM

3.1 .t Operations ot' lrriptioir I)clivcry System

Tlic most important operational olijcctivc of a11 irrigation dclivcry systciii is considcrcd to be the provision of rcliablc arid cquitablc irrigiition watcr supplics to all of thc secondary and tci-tiiiry units scrvcd by thilt systciii. 1 laving this in niind, opcralions ofthc 1 Icran Distributary wcrc nionitorcd to dctcnninc tlic naturc and cxtcnt of Iluctuations occurriiig in canal watcr supply and tlicir cffccts 011 watcrcourscs. I~Iows wcrc iiicasurcd twicc it wcck on the sanic days at tlic hciid rcgulator as well ils at all ol'tlic oiitlcts ~I'tlic I lcraii Distril~iiIi~~y.

3.1.1.1 Irrigation Supl)lirs at Ilcad Kegillator of tlic 1lrr;rn Distributary

Avcragc monthly vnlucs for dischargc at tlic hcild rcgulator 01' tlic Mcran Disrributary froiii April to Scptciiibcr 1997 arc prcsciitcd in Figurc 3.1. 'fhc rcsults show that the avcragc iiionthly dischargc receivcd at tlic licad of thc ltcran Distributary was much niorc as compnrcd with its old dcsigii dischargc, which would bc cxpcctcd. Tlic dischargcs wcrc also not vciy di ffcrciit from onc month to tlic otlicr cxccpt for tlic month of April, wlicii thc avcragc dischargc was signi ficii1itly lowcr than tlic othcr months. Tlic rcason for the low supply in April could bc rcliitcd to a transition bctwecii the rabi and khari f scasoiis.

Thc avcragc tctiiporal cocfficiclits of variability calculatcd for thc monthly supplies at tlic licad rcsulator arc prescntcd in Figurc 3.2. They wcrc found within acccptablc rangc i.c. bcing in thc fair to good category according to Moldcn and Gatcs ( I 990) critcria. This mcans that thc variations obscrvcd in thc irrigation supplics at thc licad of thc f Icran Distributary wcrc acccptablc and tlic iiiain systciii opcrations wcrc foiind to bc rcliablc.

10

la

9

8

7

6

5

4

3

2

1

0

/

/

/

/

/

/

/

/

/

.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...................... ......... ...

................ ......... ..... .. ........ -. ...... ...

.................... ~- -_- .... ....

c 77 7.04

d APRIL MAY JUNE JULY

Months

I I

AUGUST SEP

Figure 3.1 Monthly average discharge entering Heran Distributary for Kharif 1997.

1

0.9

0.8

0.7

+ C 0) '6 0.5 5 0 0 - [ 0.4 E 2

0.3

0.2

0.1

0

~ .. ... . - . . . . _ _ ..... ..

0.1 0.1 0.1 1 0.12

A . A v

0.09 0.08 I I I I

APRIL MAY JUNE JULY AUGUST Months

SEP

Figure 3.2 Temporal Coefficient of Variability at head regulator of the Heran Distributary for Kharif 1997.

I2

3.1.1.2 Irrigation Supplies at Watercourse Outlets

Thc typc of outlct and its opcrating condition for all of thc outlcts froin thc Hcrati Distributary arc shown i n Tablc 3.1.

Tablc 3.1 Typcs of outlcts and their operating condition (Heran Distributaly).

.# OUTLET # TYPE OF OUTLET FLOW CONDITION

I -I, AI’M Submcrgcd Ori ticc

2-R APM Free Orifice.

3-L AI’M Submcrgcd Orilicc

I. 4-I< APM Submcrgcd Orifice

1. 5-L A I’M Frcc Orifice.

1. 0-1, APM Suhmergcd Ori licc

’. 7- L Al’M Frcc Orifice.

i. 9-AR APM Submcrgcd Orifice

1. 8-L AI’M Frce Orificc.

10. 9-I< AI’M Frec Orifice.

11. 10-I< AI’M . Submerged orificc

12&13 I1+12-R A I’M Submcrgcd Orificc

14. 13-R AI’M Free Orifice

15. 14-1, APM 1:rcc Ori ficc

16. 8-AL APM Frec Orifice

17. 15-L APM Free Orifice

18. 16-K APM Submcrgcd Orifice

19. 17-AL APM Frcc Orifice

20. 16-AR Opcn Flume Submcrgcd

21. I7-Dla AI’M Frcc Orificc

22. 18-R Opcn Flume Submerged

23. 17-T Open Flume Submerged

, 24. 18-T Open Flume Frce Flow

13

Tlic type of outlct and its opcl-rrting conditi.on for all of tlic outlcts li.oni tlic Kliadwari Minor arc shown in Table 3.2.

Tablc 3.2 Typcs of outlcts and thcir opcrating condition (Kliadwari Minor).

Irrigation supplics iIt watcrcoursc outlcts wcrc mcasurcd at thc saiiic timc as tlic discliargc mcasurcments at tlic head rcgulator. Tlic monthly data (eight obscrvations i n cadi month) wcrc nornializcd on tlic bilsis of watcr duty in cfs/lOOO acrcs. Tlic avcragc monthly discliarge valuc for cach outlct is prcscntcd in Figurcs 3.3 through 3.8.

Figurc 3.3 shows that tlicre is no pattcrn of watcr distribution among tlic outlcts. Two watcrcoursc outlcts (Outlets 7-L and 10-R) arc drawing cxccptionally high discliargcs. About lialf of tlic outlcts wcrc drawing liiglicr dischargcs comparcd with the rcst. Wlicrcas two watcrcoursc outlcts (Outlcts 2-K and 3-L) wcrc drawing significantly low discliargcs whcn comparcd with tlic rcst. This trciid niorc or less continucd during otlicr niontlis us wcll. From tlicsc figurcs, it is c l c ; ~ that tlicrc was a li\rgc variation i n iiliiol1Iits of watcr bcing clrawn by cli ffcrciit outlcts.

Tlic distribution of watcr among thc outlcts is the niain conccrn of the watcr uscrs / fam1crs. Tlicreforc, thc distribution of watcr among thc outlcts was cvaluatcd using tlic tcrin "cquity", wliicli indicatcs the ability o f a systcni to distribute water uniformly ovcr space. Thc distribution of watcr is usually influcnccd by a number of potential factors, which cause a non-unifonn watcr distribution along a parent clianncl. They niay includc lack of propcr maintcnancc, scdimcnt dcpositioii, tanipcring ofoutlcts, and illcgal watcr abstractions.

Tlic data wcrc dnalyzcd to dctcrminc tlic spatial coefficient of variability for cach month. Tlic rcsults arc shown in Figurc 3.9. Figurc 3.9 shows that thc spatial coeffcicnt of variability for thc outlcts rangcd from 0.39 (39%) to 0.48 (48%) wliicli imylicd that tlic watcr distribution along tlic outlcts was in tlic "poor" catcgory according to Molden and gatcs ( 1 990).

14

I

I

I

- - .---- .. - . . .. . -. ..

1 t-t-t-tl-+--t--1--t-l-t----~ -+---k-l--i--t--t-- 2-R

3-L

4-R

5-L

6-L

7-L

9-AR

6-T

6-T

F 4

t

I

1 -

R e nr

2-R

3-L

4-R

5-L

6-L

7-L n 5.

s 9-AR

4 1 1 1 I + - t - + - + - f - $ - t - . 1 t i - M + 1

I

\ I / \ I I

.-

1

c Y

(D (D

c_ 4

Y

\ I

i ' I

5-T

6-T

.- 6-T

s 10-R 2 11+12-R e

a

I I

I I

l I I

I t I

16-AR

17-BL

18-R

17-AT

18-AT

R r" ar

I \ I \ \

1 T I

- m 3 4

i

I

-..-. . . ^-

-9

1-9

1%

t l -P

1%

t l -2

1- 1

WY 1V-1

lV -8 1

I V - L 1

t l -8 1

iw 1

tlv-9 1

1V-L 1

tl-9 1

1-S 1

1-P 1

W E 1 I I

t l - Z l + l l

tl-0 1

1V-8

tl-6

1-8

tlV-6

1-L

1-9

1-S

t l -P

1-C

L Q) n E 3 z Q)

$

4 0

0) 2 4

19

2 0

Temporal coefficients or variability at outlcts wcre calculated to see thc fluctuations over time. These are presented in Figure 3.10. The temporal cocfficicnt of variability'varied from 0.18 (1 8%) to 0.24 (24%), which is comparatively small, thereby implying that cach outlet was drawing proportionally the same amount whcthcr the distributary had incrcascd or Jccrcascd irrigation watcr supplies.

Date 2R 2RDay 11+12R Night Night

The results presentcd above imply that the watcr distribution was not cquitable and, therefore, cquity may be ratcd as poor. Dctails of thc tlischargc mcasurcmcnt data arc prcscntcd in Annex A.

18R HR HR Day Night Day Night Day

11+12R 18R

3.1.1.3 FIuctuations in Watercourse Supplies

Flow measurements on sarnplc watercourses selected from thc hcad, middlc and tail portions of the distributary wcre undertaken continuously for 6 days to dctermine the fluctuations in the watercoursc supplics. Tlic rcsulting data arc prescntcd in Figurcs 3.1 1 through 3.10 ror thc Heran Distributary and Figurcs 3.17 through 3.22 for the Khadwari Minor.

0.000

0.004

0.002

0.004

Tlic figures show that thcrc wcre rclativcly sinall variations in irrigation supplics during thc measurement period. Also, variations between the day and the night irrigation supplics wcrc not significant.

1 1

0.002 0.0 10 0.024 0.050 0.030 0.000 0.000

0.008 0.018 0.032 0.025 0.050 0.000 0.006

0.005 0.04 1 0.01 1 0.066 0.049 0.001 0.001

0.004 0.04 1 0.021 0.056 0.02 1 0.00 1 0.001

Cocfficicnts of tcinporal variation for clay and night dischargc mcasurcnients wcrc calculatcd for the head regulator, as well as for the thrcc sarnplc watcrcourses. Thcy arc prcscntcd in Tablc 3.3.

Table 3.3. Coefficicnt of temporal variation for day and night discliargc mcasurcnicnts of Heran Distributary, Sanghar.

18-19

19-20

20-2 1

2 I -22

I 23-24

21

3 E .; 0.6 L a

$

- 0.3 -

0.2

0.1 - , --_

0

L ,o ,g 0.5 ).

,- g Q 0

2 m 0.4 c c. m P v)

-- - _-

0.47 0.48 0.48 *

4r - 0.46

0.4

APRIL MAY JUNE JULY

Months AUGUST SEP

Figure 3.9 Spatial Coefficient of Variability among the outlets from the Heran Distributary for Kharif 1997.

22

1

0.1 -

0.9

0.8

0.7

* 0

- e Op. 0.4 E c

0.:

0.:

0.1 8

o ! I , APRIL MAY JUNE JULY

Months AUGUST SEP

Figure 3.10 Temporal Coefficient of Variability at outlets from the Heran Distributary for Kharif 1997.

23

Q)

P

I

25

I a 0

Ip t 8 "

1

8.00

E

n f 4.00

2.00

+2R

-#- HR

-A

- 11+12R

+ 18R

, 0.00

J ,

,

20 21

22 23 24

1 2

3 4

5 6

7 8

9 10

11 12 13 14

15 16 17 18

Tim

e (h

ours

)

Figu

re 3

.14

Dis

char

ge of H

eran

Dis

trib

utar

y an

d its

sam

ple

outle

ts

(Aug

ust 2

1122

,199

7).

0 4.00

n 5 c f 2.00

+ 11+12R 11

-- --

, I

I

Figu

re 3

.15

Dis

char

ge o

f Her

an D

istr

ibut

ary

and

its s

ampl

e ou

tlets

(A

ugus

t 221

23,1

997)

.

6.00

3- 4

.00

a s L z

2.00

--t 2

R

-C-

HR

' +-

11+1

2R

+18R

0.00

! f

, I

I I

I I

, ,

20

21

22

23

24

1 2

3 4

5 6

7 8

9 10

11

12

13

14

15

16

17

18

Tim

e (h

ours

)

Figu

re 3

.1 6

Dis

char

ge o

f H

eran

Dis

trib

utar

y an

d its

sam

ple

outle

ts

(Aug

ust 2

3124

,199

7).

6-

W

25

0

0' 2" L2

Q

) C

I

1

-m-

K.W

Min

or

I +4-R

0 1

t t

8 I

20

21

22

23

24

1 2

3 4

5 6

7 8

9 10

11

12

13

14

15

16

17

18

19

Tim

e (h

ours

)

Figu

re 3

.17

Dis

char

ge o

f Kha

dwar

i Min

or a

nd a

sam

ple

outle

t (18

/19

Aug

. 199

7).

7 6 1 0

-a-

K.W

Min

or

I_L/1(

I

I I

I

20

21

22

23

24

1 2

3 4

5 6

7 8

9 10

11

12

13

14

15

16

17

18

19

chou

w

Figu

re 3

.18

Dis

char

ge o

f Kha

dwar

i Min

or a

nd a

sam

ple

outle

t (19

/20

Aug

. 199

7).

d

2 E

W

w

L2

d

1 0

- \

1 I

I L

1

20

21 22

23

24

1 2

3 4

5 6

7 8

9 10

11

12

13

14

15

16

17

18

19

Tim

e (h

ours

)

Figu

re 3

.19

Dis

char

ge o

f Kha

dwar

i Min

or a

nd a

sam

ple

outle

t (20

121

Aug

. 199

7).

- -- .-. . .- . . . .- .. -. - .- . .- ... . . . - - ... . . .

0

cc 0

35

Also, cocfficients of tcmporal variation on an hourly basis wcrc calculated for tlic head regulator, as wcll as for tlic threc samplc watcrcourses. Thcy arc prcscntcd in Tablc 3.4.

2R - Date

18-19 0.000

19-20 0.007

20-2 1 0.005

2 1-22 0.004

22-23 0.007

23-24 0.009

HR - - - - -_ - __. .__-_-_I--_ - 11+12R 18R . ___

0.0 1 0 0.060 0.000

0.04 1 0.041 0.007

0.037 0.06 1 0.00 1

0.046 0.052 0.001

0.065 0,062 0.001

0.021 0.038 0.005

3.1.1.4 Irrigation Delivery I’crformance

The summary of irrigation dclivcry pcrformancc is given in Tables 3.5. Thc summary indicates that thc most scrious problcnis arc at tcrtiary lcvcl rathcr than at tlic main systcm lcvel. Thesc problcnis can succcssfully be rcsolvcd tllrough tlic coopcration of concerned farmers and their WUAs.

Average Dischargc at head

regulator (cfs/lOOO acres)

4.85

6.3 1

6.6 1

7.04

6.44

6.77

Table 3.5. Performance summary of irrigation dclivcry system of the Hcran

Temporal Spatial cocfficicnt of Tcmporal cocflicicnt of variability cocfficicnt of

variability at head at outlets variability at regulator outlets

0.12 0.47 0.24

0.09 0.48 0.2 1

0.1 I 0.46 0.1 8

0.10 0.48 0.20

0.10 0.39 0.20

0.18 0.08 0.40 ~-

Months

Apri 1

p August

1 September

36

3.1.2 Maintenance of Irrigation Delivery System

3.1.2.1 General Maintenance

The Heran Distributary was monitored periodically for documenting the rnaintenancc conditions and practices. The monitoring of general maintenance activities revealed that the only maintenance activity undertaken was “desilting** which was done during the annual canal closure period. No other maintenance activity was undertaken subsequently. Most of the outlets were found tampered and, therefore, draw more water than their due share.

3.1.2.2 Physical Conditions

The physical condition of a channel has considerable bearing on the conveyance and distribution of water among the outlets. Walk-thru surveys and farmers’ interviews were undertaken to assess the physical condition of the channel. During these surveys, efforts were made to record vegctation growth, wcak points of banks and bcrms, condition of thc inspcction path (bcnn used for travelling) and non-inspcction path (berm on oppositc sidc of thc clianncl from thc inspection path), and physical condition of thc outlets.

Presence of vegetation in the irrigation system is a niajor source for disturbing the flow of water. This also leads to changes in flow conditions such as from free-flow to submerged-flow. The vegetative growth was classified as follows:

Class I : Clean (vegetation less than 1 foot high)

Class I1 : Very little (Vegetation betwccn 1-2 feet high)

Class 111 : Little (Vegetation between 2-3 fcet high)

Class 1V : Moderate (Vcgetation between 3-5 fcet high)

Class V : Thick (Vegetation grcatcr than 5 fcet in height)

The average physical conditions observed during the surveys are presented in Table 3.6. The data on vegetative growth show that the Heran Distributary has high vegetative growth at some locations on both sides of the channel. This disturbs the smooth flow of water by decreasing the velocity and consequently, sediment dcposition takcs place. Thc banks were obscrvcd to bc in good physical condition cxcept at a few placcs.

37

3.2 DRAINAGE DISPOSAL SYSTEM (DDS)

The Hcran Distributary command arca has a nctwork of surfacc drains. In addition to the drains, thc compound (scavcngcr) tubcwclls and drainagc tubcwclls havc bccn installed in the command area. Specific details on drainage facilities arc providcd in Table 2.4.

38

3.2.1 Operations of Drainage Systeni

3.2.1.1 Drainage Emuent

The tubewells are not yct operational. The surfacc drains arc functioning and contributing drainage effluent to the drainage disposal system. The network of surface drains in the Heran Distributary command area were identified. The inflow (source) and outflow (disposal) points of the drainage effluent were located. The term %ourcel' indicates thc inflow of drainage effluent from thc upstream command arca cntcrs into the Hcran Distributary command arca and thc term "disposal" indicates the outflow of tlic drainagc cmuent leaving from thc Hcran Distributary command arca (inflow at sourcc siibtractcd from outflow at disposal, gives the net drainage effluent from thc comniand arca). Thc discharge of the drainage cffluent was measured at the source and disposal points by currcnt metering oncc cvcry month. Tlic rcsults arc prcscntcd in Table 3.7.

Tablc 3.7. Contribution of thc surfacc drains in Iicran Distributary command arca, Sangliar.

Tlic rcsults show that thc driliI1ilgc cfflucnt is vcry smnll. This will bc incrcasctl when the drainage tubewells become operational.

3.2.1.2 Watcr Table Depth

There were 86 piezomctcrs installed in the conimand arca of tlic llcran Distributary to monitor watcr tablc fluctuations. Thc watcr tablc fluctuations wcrc obscrvctl on a monthly basis. Tlic avcragc monthly willcr tablc dcpllis arc shown in Figurc 3.23.

As shown in thc figurc, thc avcragc watcr table dcpth in the Hcran Distributary command area is high (about 2.6 fcct). This certainly has dctrinicntal cffccts on crop production. No significant variation in thc water table dcptli was observcd during thc kharif season. With conimissioning of thc drainagc tubewclls, the watcr tablc will inovc downwards.

39

The piezometer location and averagc watertablc depth in each piezometer is shown in Figure 3.24.

3.2.13 Groundwatcr Quality

To monitor groundwater quality, water samples wcre collected from each piezometer on a monthly basis and the electrical conductivity was mcasured. Also, a detailed chemical analysis of these samples was done on a quarterly basis. The results arc presented in Table 3.8. The results of the water quality analysis indicate that most of thc watcr samplcs wcrc in thc rangc of marginal quality to hazardous. Thcrcforc, tlic ground water cannot bc used directly for irrigation purposes. Even after mixing, or treating, care has to be taken for its long term effects on the soils and crop production.

3.2.2 Maintenance of Drainage System

The surface drains lying in the command arca wcrc survcycd. Thc obscrvalions have been summarized in Tablc 3.9. The physical condition of the drains was found satisfactory. Tlic only major problcni idcntificd was tlic vcgctative growth.

40

/ / / /

R x l7

41

N

P

t4

' 0

4.9

0

t 0 I

I

f 0

I 2*z

I 2.

91

1"'-

------J

.*

,' I

LEG

EN

D

P;e

rom

e:er

0

Dra

in

----

I

. Fi

gure

3.2

4 Pi

ezom

eter

loca

tion

and

aver

age

wat

erta

ble

dept

h fo

r Kha

rif 1

997

in th

e co

mm

and

area

of H

eran

Dist

ribut

ary,

San

ghar

.

43

Table 3.9. Vegctative growth anti wcak-portion survcy of surface drains in thc Hcran Distributary command. area, Sanghar.

0 to 6.56

6.56 to 8.2

Distance Vcgetativc Growth Comments RD

I I Le Tt Right Bottom

S- 1 I< Drain

0 to 6.56 1 5 1 Dank Sr Bcrm almost good all along its Icngth

6.56 to 9.84 1 1 1 do

9.84 to 13.12 1 5 1 d 0

13.12 to 16.4 1 5 1 do

1 5 1 do

1 2 1 do

16.4 to 19.68 1 5 1 do

19.68 to 22.90 I 5 I

I . ~ ~~

22.96 to 26.24 I

0 to 6.56

6.56 to 11.81

I

1 5 1 d 0

1 5 1 do

0 to 9.84 1 5 1 do

9.84 to 14.70 1 5 I do

14.76 to 18.37 I 5 1 do i

44

4. CONCLUSIONS

From thc rcsults and discussions prcscntcd in Scctions 2 aiid 3, tlic following conclusions wcrc rcachcd.

- The actual irrigation watcr supplics at tlic hcad rcgulator o f thc Hcran Distributary arc morc than the old designcd discliargc (1930s). Thcir "reliability" at tlic licacl rcgulator is within an acceptable rangc according to Moldcn and Gates (1990) critcria. Tlicrcforc, thc main systcm pcrformancc is ratcd as satisfactory.

- Irrigation water distribution aniong the outlcts (cquily) is found to bc very poor according to tlic criteria of Moldcn and Gates (1990). This situation nceds to bc improved through coopcration and conccrtcd cfforts to bc madc by tlic watcr tiscrs thorough thcir WUAs

, and WUF.

- DUC to a lack of propcr tnaintcnancc, uni forni watcr distribution is grcatly arrcctcd. Particularly, tlic prcscncc of high vcgctation on thc banks or llic I-lcraii Distributary rcduccs the vclocity of flow and incrcascs scdinicnt dcposition. Bccausc of this silt dcposition, the flow dcpth (hcad) iiicrcascs and niorc watcr is- drawn by thc surrounding out~cts.

- The watcr tablc dcpth has gonc high and iiccds immcdiatc attcntion. Commissioning of the drainagc tubcwclls may bc undci-takcn quickly to lower the watcr tablc.

- The ground water quality is brackish as the watcr samples collcctcd from the piczonictcrs were in the niarginal and hazardous range. Hcncc, this groundwatcr cannot be uscd for irrigation purposcs.

- The surface drains wcrc i n good physical condition. Howcvcr, vegctativc growth nceds to bc chcckcd for thcir crficicnt functioning.

1W FERllN CES

Moldcn, D. and Gatcs, T. K. 1990. Mcasurcs of Evaluation 01' Irrigation Watcr Dclivcry Systciiis. In Journal of Irrigation aiid Drainagc Enginccring, Volumc I 16, No. 6, ASCE, USA.

45

4. CONCLUSIONS

From tlic results and discussions prcscntcd in Scctions 2 and 3, thc following conclusions wcrc rcaclicd.

- The actual irrigation water supplics at thc hcad rcgulator of thc Hcran Distributary arc morc than the old designcd discliargc (1930s). Thcir "reliability" at tlic hcad rcgulator is within an acceptable rangc according to Moldcn and Gates ( 1 990) critcria. Thcreforc, tlic main systcm pcrformancc i s ratcd as satisfactory.

- Irrigation water distribution among the outlcts (cquity) is found to bc very poor according to thc criteria of Moldcn and Gatcs (1990). This situation nceds to bc improved through cooperation and conccrtcd cfforts to be niadc by tlic watcr uscrs thorough thcir WUAs and WUF.

- Due to a lack of propcr niaintcnancc, uni forni watcr distribution is grcatly affcclcd. Particularly, tlic i>rcscncc of high vcgctation on thc banks of tlic I-lcran Distributary rcduccs the vclocity of flow and iiicrcascs scdimcnt dcposition. Bccausc o f this silt dcposition, the flow dcpth (hcad) incrcascs and moic watcr is- drawn hy tlic surrounding outlets.

- The watcr tablc dcpth has gonc high and nccds ininicdiatc attcnlion. Coniniissioning of the drainagc tubcwclls may bc undci-takcn quickly to lower the watcr tablc.

The ground water quality is brackish as the watcr saniples collcctcd from thc piczomctcrs were i n the marginal and hazardous range. 1-icnce, this groundwatcr cannot be uscd for irrigation purposcs.

I -

- The surface drains wcrc in good physical condition. Howcvcr, vcgctativc growth nceds to bc chcckcd for thcir cfficicnt functioning.

KEFERENCES

Moldcn, D. and Gatcs, T. K. 1990. Mcasurcs of Evaluation of Irrigation Watcr Dclivcry Systems. In Journal of Irrigation and Draiiiagc Enginccring, V O ~ U I T ~ C 1 16, No. 6, A X E , USA.

45

ANNEX A. DISCHARGE MEASUREMENTS

46

Table A 1. Actual Discharge at thc head of Heran Distributary and Kliadwh-i Minor.

Mcasuring Date Hcad of Khadwari Minor c fs

.4.97 1 73.91

1.4.97 1 08.95 ~~

0.4.97 1 67.5

6.4.97 1 54.29 18.93

18.7 :2.4.97 I 84.17

84.15

106.55

16.15

16.15

13.4.97

10.4.97

!.5.97 108.191 17.85

9.5.97 1 10.27 17.33

5.5.97 89.47 12.98

90.32 1.5.95

14.5.97

15.08

16.09 110.84

16.5.97 110.4 16.64

10.03

15.98

97.12 21 S.97

24.5.97 103.43

2.6.97 97.86

6.6.97 103 I 15.6

9.6.97 89.47 13.6

1 1 1.35 15.69 13.6.97

18.6.97 08.93 I 15.0

2 1.6.97 113.75 19.5

116.88 17.97 26.6.97

28.6.97 124.99 I 19.03 I

2.7.97 114.06 I 17.54

47

Table A1 . (CoiiiDlete)

48

Table A2. Dcsigri and avcragc cxisling duty at licad rcgulator of I-Icran Distributary and Khadwari Minor.

Moiitli H cra 11 D i s t r i IN t ary Khatlwari Minor

Desigii Duty Avcragc Dcsign Duty Avcragc Existing Duty (cfs/lOOO ucrc) Existing Duty (cfs/I000 acrc) (cfs/lOOO acrc)

(c fs/ I 000 acrc)

April 77 3.75 5.27 3.43 5.70

May 97 3.75 6.64 3.43 4.93

Junc 97 3.75 6.90 3.43 5.43

July 97 3.75 7.36 3.43 0.0 1

August 97 3.75 6.76 3.43 5.02

Scptcmbcr 97 3.75 7.09 3.43 0.02

49

Table A3. Discharge measurement at each outlet through tape readings for the month of April 1997.

Table A4. Discharge measurement at each outlet through tape readings for the month of May 1997.

Table A5. Discharge measurement at each outlet through tape readings for the month of June 1997.

52

Table A6. Discharge measurement at each outlet through tape readings for the month of July 1997.

53

Table A7. Discharge measurement at each outlet through tape readings for the month of August 1997.

16-AR 2.32 2.85 2.20 3.16 2.87 3.20 1.61 1.98 2.52 17-BL 2.55 2.22 2.48 2.95 . 2.96 2.88 1.71 2.20 2.49 18-R 2.73 2.37 2.77 2.32 2.47 2.68 2.03 2.38 2.47 17-AT 3.78 2.84 3.69 3.85 3.65 3.91 2.32 3.1 6 3.40

54

Table A9. Average discharge measurement for Kharif 1997.

10-R 5.97 5.61 5.87 4.57 5.97 6.41 6.52 6.30 5.90 11+12-R 7.40 7.69 8.71 8.24 7.30 9.86 9.40 9.09 0.47 13-R 2.45 2.33 2.74 1.64 2.46 2.62 0.00 0.00 1.78 14-L 3.14 3.01 3.29 0.00 3.09 3.1 8 3.26 3.20 2.78

-

Table A8. Discharge measurement at each outlet through tape readings for the month of September 1997.

17-AT 18-AT

1-AL KM 1 -L

1

5-L 1.56 2.28 2.58 2.44 3.56 3.95 2.73

6-L 7.64 9.00 7.99 7.77 3.26 3.1 1 6.46

2.50 4.38 3.60 4.30 3.40 4.16 3.72

3.03 4.55 3.80 4.55 4.30 4.44 4.1 1

1.99 2.20 2.54 2.61 2.1 5 2.81 2.38

1.68 2.38 2.95 2.83 2.00 2.45 2.38

7-L 2.85 4.45 4.67 4.58 5.1 6 5.79 4.58

9-AR 1.79 2.1 1 2.25 2.1 8 2.1 4 2.33 2.13

8-L 3.45 4.03 4.80 4.97 4.93 4.76 4.49

9-R 4.59 6.08 6.13 5.68 6.04 5.54 5.68

4-R 5-T 6-T

Total Head

8-AL 3.02 3.58 3.78 4.36 3.41 3.83 3.66

1 O-R 4.27 4.51 5.29 5.71 5.94 5.90 5.27

11+12-R 6.70 7.07 7.32 7.69 9.56 8.47 7.80

13-R 2.03 2.59 2.36 2.54 2.31 1.78 2.27

14-L 2.26 2.80 2.99 3.1 5 3.09 2.78 2.85

2.08 2.39 2.47 3.41 2.61 3.02 2.66 2.26 2.34 2.49 3.00 2.98 4.02 2.85 0.34 1.06 1.19 1.77 1.17 1.58 1.18

80.61 101.48 104.47. 109.74 102.32 106.37 100.83

81.36 102.51 107.03 1 13.71 104.37 109.55 103.09

~~

15-L 1 1.76 I 2.17 I 1.83 I 2.02 I 1.86 I 1.95 I 1.93 11 16-R 3.37 4.05 3.63 3.76 2.86 3.71 3.56

17-AL 2.51 3.70 3.71 . 3.87 3.47 3.95 3.54

16-AR 1.97 2.89 3.23 3.1 4 2.52 3.73 2.91

17-BL 1.45 2.57 2.54 2.64 2.49 2.51 2.37

18-R 1.81 2.34 2 -36 2.68 2.47 2.41 2.34 1

2-R I 1.37 I 1.94 I 2.68 I 2.68 I 2.06 I 1.78 I 2.08 11 3-L I 1.82 I 1.54 I 1.62 I 1.94 I 1.83 I 1.87 I 1.77

56

r ,