Rotational Water Supply (RWS) is a method of distributing. water to all farmers of the command area in proportion to

Transcription

1 I Chapter 6- COMPUTERS AND WATER DISTRIBUTION SYSTEM, ] Rotatonal Water Supply (RWS) s a method of dstrbutng water to all farmers of the command area n proporton to ther land hodng[68]. Ths method s becomng more and more popular n, the state of Gujarat. However, the whole process nvolved n ths system s a lttle more complex than one thnks of t and s not easy to explan n one go, to t'he engneers n the feld. We have desgned and developed a CAI package to explan the s' : followng through graphcs and audo-vsual effects. - (Jjoncept! of canal dstrbuton. / - Outlet ; dstrbuton and water allocaton to dfferent felds. The 'package s standardzed on the experences ganed by gettng the feedback from varous levels of people. Ths package has been mplemented at WALMI (Water and Land Management Insttute), Anand. Product brochure s provded at the end of ths chapter. t \ 1. Background Ponts. Snce ndependence, large number of rrgaton projects have been constructed and huge Irrgaton potental was created by harnessng rvers. Stll, there s a wde gap 1 between created rrgaton potental and rrgaton potental: used.! Many farmers do not receve water at rght tme and n rght quantty. One of the reasons for such a stuaton: s lack of proper method of water dstrbuton. For unform. and equtable dstrbuton of 130

2 ' water, prerequste s to understand about canal network as well as. water :d st r but 1 on methods. 2. Tradtonal and popular method of water dstrbuton SHEJPALI In Gujarat, for dstrbuton of water down the outlet, SHEJPALI method 1s practced n general. In SHEOPALI, 1 * Farmers submt applcaton forms. * Requrement of water s worked out by past experence. * Applcatons: are processed and passes are ssued. * Canals run as per farmers demands. j * Canals run wth partal dscharge.! * Tmngs fo;r rrgaton are not fxed. In an ' arbtrary manner rrgaton sequence s decded. 3. Rotatonal Water Supply (RWS). RWS s a methojd of water dstrbuton to all farmers of the command area! n proporton to ther land holdng. Ths type of water dstrbuton assures equtable water to all the farmers n ; proporton to ther land holdng. Ths method s beng apprecated and s expected to be followed wdely n Gujarat1. In RWS, * All farmers ;get equtable quantum of water. - * Tme allocated to each farm (Holdng or Feld) s predetermned by the weekly schedule. * All outlets of the mnor under a canal functon on twenty fou'r hour schedule. rrgaton clompulsory. Ths makes nght 131

3 * All channels'are operated at full supply level wth I- desgned dscharge. * Outlets are desgned to delver fxed dscharge n proporton to the command area. 4. Software Implementaton Methodology. Snce RWS s a new method of water dstrbuton and t s expected to be fol owed, t s necessary for the exstng engneers j n the feld to know about the whole system. It s not possble to explan about the whole process to the engneers n one go, because of ts comp!exty. To tran engneers on RWS usng computers, we have dentfed the followng components. ; \! - Structure of ;Canal Network. - Canal network and water dstrbuton termnology. - Preparatn of RWS schedule. - Smulaton of felds gettng water. - Preparaton!of RWS schedule by engneers wth ther own data. 4.1 Structure of Canal Network : Water of a rver ;1s dverted n to a channel whch s known as man canal usng a dverson. From man canal, water wll be dverted nto channels known as branch canals or dstrbutares. Each dstrbutory s dvded nto mnors or submnors. There are many outlets on a mnor (or sub mnor) whch connects the farmng localty to the publc water dstrbuton system. From outlets, water flows through water courses. On each water course, there are turnouts whch are. jused to connect felds and Water courses through a feld channel. Each feld wll be havng feld 132

4 Inlet through wh;ch felds get water. Ths s the structure of the canal network whch should be clear to the engneers those'who deal wth water dstrbuton. Vsual presentaton of the canal network.s dscussed n software mplementaton whch s descrbed n the followng pages. 4.2 Canal Network and Water Dstrbuton Termnology : Man Canal : A channel carryng water from a reservor usng a dverson 'bcrossa rver. Branch Canal : A ( channel carryng water from man canal wth a \! dscharge more than 100 cusecs. In general, there wll be more than onelbranch canal comng out of a man canal. Dstrbutory : A branch canal s known as dstrbutory, f the dscharge s between 25 cusecs to 100 cusecs. Mnor : A channel carryng water from man canal, branch canal, dstrbutory wth a dscharge capacty less than 25 cusecs. ; Chak :! ; Command area about 30 to.60 hectares wth ungated outlet havng fxed dscharge of water correspondng to the peak demand. Sub-Chak : Sub dvson ofa chak, typcally about 5-8 hectares n s^ze. 133

5 Outlet : Inlet to a chak wjth ungated fxed dscharge devce. Water Course : Channel off-takng from mnor and havng dscharge between 0.5 to 1.'5 cusecs. Turnout : Inlet to a sub-chak wth an open shut gate. Feld Channel : Channel takng supply from water course.e from turnout to feld rnlet. Feld nlet : ; Inlet to a farm., 4.3 Preparaton of RWS schedule : To prepare RWS schedule the followng crtera should be consdered. I - The tme allocated to each farmer should be on the bass of week: and for day and nght rrgaton,.e. total tme^ to be consdered s 168 hours. - The allocaton of rrgaton tme for each holdng should be proportonate to ts Culturable Command Area (CCA). : - The desgn of RWS schedule should am at achevng equtable d1 str but on of water wth the nvolvement of farmers.! - The schedules' are to be prepared by consderng a fxed outlet dscharge but varyng ntervals between waterng, dependng upon needs of crops. Water dstrbuton j consdered to be completed n a base 134

6 tme of 7 days (.e. one week) accordng to the followng ponts. * Transt 1 o; s s e s n the feld channel are I compensated ; by enhancng the area of the feld. Ths area s known as notonal area. Notonal area of the chak 's worked out by enhancng the physcal area by dvdng by a factor dependng upon the extent of the seepage losses n the relevant length of feld channel. * Transport tme shall be allowed from the common pool at th;e rate of 1.0 hr/100 mts ^ (consderng velocty of water at 0.30 mt/sec.) for the effected le;ngth of feld channel to the concerned /farmers. * Base tme n hours of CCA per week s equal to total transport tme of chak total notonal area of chak 4.4 Steps requred for preparng RWS schedule ; Step 1 : Fnd the servce area at the outlet head. Step 2 : Determne the CCA of chak. Step 3 : Determne 'the dscharge requred for the outlet usng the followng formula. Servce Area.e. I Command area of outlet Step 4 : Enlst names of farmers under column 3, survey numbers under column 4, and CCA under column 5. Step 5 : Fnd the ;length of feld channel from turnout (.e. dstance of the nlet from the turnout) and enter under column 6.! 135

7 Step 6 : Workout relevant dstance from one nlet to subsequent nlet and efter under column 7., Step 7 : Workout dstance between one turnout to subsequent turnout for calculatng transport tme and enter under column 8. Step 8 : Calculate percentage seepage loss at the rate of 3% per 100 meters^ for the dstance under column 6 and enter under column 9. Step 9 : Calculate dvdng factor by deductng losses from column 10 and by dvdng t wth 100. Step 10: Calculate notonal area by dvdng CCA by dvdng factor and enter under column 11. Step 11: Calculate the transport tme (TT) at the rate of 0.1 v hr/100 mts ;of related dstance (under column.7 and dstance between T.O. to T.O.) and enter under column 12. : Step 12: Calculate base tme (BT) from the followng formula 168 -total of column 12 BT = Total Notonal Area (.e. total of column 11) Step 13: Calculate tjme allocated and enter under column 13. Tme allocated «= NA * BT = column 11 * BT Step 14: Calculate f;1nal tme allotted and enter under column 14. Fnal tme Tme allocated + TT Step 15: Convert fnal tme nto hours and mnutes and enter under coluum 15. Step 16: Prepare the! weekly schedule startng from 8.00 A.M. and go on addng the fnal tme and obtan tmngs for each r feld. 136

8 4.5 Smulaton of felds gettng water : Man objectve of ths smulaton s to show the learner, the dstrbuton of water under dfferent outlets concurrently. To acheve ths objectve, a mnor s taken wth three outlets and a water course comng out of each ( t- outlet. A few number of felds are taken under each outlet. Felds fllng wthwater are shown slowly and effectvely wth dfferent fll desgns. Whenever a feld s flled wth water, that feld gets sold desgn and system beeps. Ths package uses colour graphcs of VGA montor to show the fllng of felds and other thngs very effectvely. For example, whenever a fled s flled wth water, feld s flled wth bluecolor. Care has been taken n fllng the felds wth water n terms of area of the feld and dstance of the feld from the outlet. 4.6 Smulaton of preparaton of RWS schedule : A screen s provded to the learner for ths ' purpose. In ths screen, a mnor wth two outlets and a few felds s are shown. Here. learner s asked to supply dfferent fgures regardng the networkng system and accordng to these,f1gures, the RWS schedule s prepared. 5. Software Implementaton. The whole package s dvded nto fve screens to facltate the learner to learn about all the components dscussed above. When the frst tme package s nvoked, system dsplays a screen (Fg. 6.1) showng the canal; network. In ths network man canal, branch, dstrbutory, mnor/sub mnor, outlets, 137

9 turnouts, feld channels, feld nlets and felds are shown. In ths screen, learner s provded wth a help faclty through pressng FI key. When FI key s pressed, a help wndow wth network termnology s dsplayed (Fg. 6.2). Learner gets-, more nformaton on network termnology by usng PgDn/PgUp keys. Components of canal network are shown n dfferent shapes and they are hghlghted wth dfferent colors. Optons are provded to the user to go to the next screen, to go to the prevous screen or to ext from the system. Next screen opton takes the learner to the next screen and prevous screen opton takes the learner to the prevous screen (except wth the frst and last screens). Second screen shows the part of canal network whch s used to prepare the RWS schedule. In ths screen, a mnor wth three outlets and a few number of outlets are dsplayed as shown n Fg Am of ths screen s to make. the learner to understand some of the terms whch are mportant n RWS schedule preparaton n 1 more detal. Ths s acheved through provdng explanaton n the- nstructon wndow and dsplayng the name of that term on the screen at the approprate place. Terms explaned through ths screen are as follows : - Outlet - Turnout (T.O.) - Feld Channel t - Dstance between T.O. to T.O. - Felds and survey numbers - Dstance between feld nlet and T.O. 138

10 Thrd screen presents the learner, the mportance of the RWS schedule and the mportant data tems that are requred, to prepare the RWS schedule (Fg. 6.4). Fourth Screen (Fg. 6.5) s dvded nto two wndows. In one wndow steps requred to prepare the RWS schedule are presented step by step. Another wndow shows the RWS schedule where columns gets flled wth data when a partcular step s executed. To prepare the RWS schedule, part 'of canal network shown n the second screen has been taken wth some relevant data. Care has been taken n creatng ths data by consderng the szes of felds and the dstances between dfferent turnouts and between turnouts and feld nlets. Learner s asked to press a key after each step, to execute another step. Each step s explaned n the wndow and accordngly the correspondng column of RWS schedule n another wndow would be flled wth data At the end, RWS schedule s ready wth tmngs shown aganst each survey number of feld. These fnal tmngs presents the day name, startng tme and' endng tme. Farmers are expected to follow these tmngs durng those days. Ffth screen s a;n mportant screen of ths system whch shows the smulaton of felds, flled wth water. Intally, learner s provded wth general nstructons reg ar dng fllng (Fg. 6.6) and later on, system wll start fllng the felds wth water wthout the nterventon of the learner. To show the fllng the felds 139

11 wth, water, dfferent fll dsgns are used to make the learner to understand the percentage of fllng. Whenever a feld s flled wth water that feld s flled wth a sold blue color and system beeps. Also to show the number of felds flled wth watpr under each outlet, a small wndow wth empty square boxes aganst outlets are provded. Intally these square boxes are empty and flled wths sold blue color, whenever a feld s flled wth water. Ths s just to make the learner to know the status of felds ;at a gven tme. At the end of the /. \ process, learner can vsualze that all the felds under dfferent felds wll be flled wth water almost at the same, t me. Last and fnal screen (fg. 6.7 and Fg. 6.8) allows the learners to prepare the RWS schedule wth ther own data. To prepare such a schedule, screen s dvded nto dfferent wndows. In one wndow, a small canal network wth a mnor, two outlets and a few felds are shown. Learner s asked to provde data regardng fejds such as survey numbers, area n hectares, dstance between turnout to turnout and the dstance between the turnout and the feld nlets.. Ths data s valdated whle acceptng as nput. After acceptng the data, system shows each step and prepares the RWS schedule. Learner can repeat ths process wth dfferent sets of data. Through thd process, learner gets understandngs about the Importance of transportaton tme, transportaton losses I (seepage losses), notonal area and base tme. 140

12 6. Advantages of CAI package. 6.1 Provdes good understandng about the Water Conveyance System as a whole and the general termnology because t s shown on the screen and explaned through help. 6.2 Shows the mportance of dstance between dfferent turnouts and: the dstance between the turnout and feld nlets jn preparng the RWS schedule. 6.3 User gets an opportunty to go through dfferent \ ; steps nvolved n the RWS schedule. 6.4 Provde clear understandng about the concurrent /water fllng: of felds under dfferent outlets. 6.5 System ncreases the confdence of users regardng the RWS schedule by allowng them to prepare RWS schedule wth; the r. own data. 7. Lmtatons of CAI package. 7.1 Shapes of felds are lmted to only a few predefned shapes for the convnence of fllng the felds. 7.2 Canals, mnors, sub mnors are shown straght for the convnence o.f showng the flow of water. 7.3 User s allowed to supply data regardng a few felds for! preparng the RWS schedule to the lmted space avalable on screen. I 141

13 Fg Screen showng Herarchcal Water Conveyance System. Fg Herarchcal Water Conveyance System wth Help Screen. 142

14 Fg. 6.3 Part of Canal network wth detals. Mar va fvtlv wth tn follow* tana : OUTLET, TERCOURE nd TUNOT (T.O.) * lstnca baton T.O. to T J. (T(K->T0) «Fald Chmal, Fald, FaU tan* IMar «Feld Inlat nd lstnca baton Tanwt nd Fald Inlat <FI<->TI) To have a glnpse of the above TERNS on graphcs press P to revew, Wth such understandng, let us nov prepare the nportant RMS Schedule. Fg Terms used n RWS Schedule Preparaton. 143

15 ysten calculates fnal tne (tne allocated^!) allotted for each feld nd enters under Col L n L2R 112 UN R UR a* I UR IN m too JM 182 UR » UR UN n ue 1R0 2UR IN L R UN UR 102 M2 131 UO w UR UR Fg Interactve RWS Schedule Preparaton. Fg Concurrent Water Supply Smulatons. 144

16 Fg Ste Engneers tool for RWS preparaton Screen I Fg Ste Engneers tool for RWS preparaton - Screen

17 ntellgent tutorng system WITH SIMULATIONS OF RWS OUTLET COMPLEXITIES. Software package: RWS 3.1 TOTAL SOLUTION FOR UNDERSTANDING OF THE OUTLET COMPLEXITIES OF RWS. The purpose of ths software package s to explan the fundamentals of Rotatonal Water Supply system to a novce. Ths system provdes an ntellgent user nterface. The system s desgned and developed nvolvng experts n the subject matter and computer professonals. Informatcs Rural Foundaton has coordnated the development of ths tool, n an effort to assst n mprovng the understandng of the emergng methodologes of water dstrbuton through RWS, whch are gong to help the rural sector at large n the country. Hardware Requrement to run tlls package : Any IBM PC Compatble Computer wth mnmum of 640 'KB RAM, VGA montor, at least one floppy drve. Software Requrement :. MS-DOS 3.1 or later verson How to run 'ths package The Floppy can be placed n A or B drve. Aganst the DOS command prompt under that drve, type RWS <enter>. The package s user frendly wth context senstve help