In Bangladesh several policies have been taken from the beginning of irrigation development. But the irrigated area reached only to 4.00 million hectares against the planned target of 7.56 million hectares by 2002. Thus rice production as well as food demands could not be achieved. Presently minor irrigation systems namely DTW (Deep Tubewell), STW (Shallow Tubewell) and LLP (Low Lift Pump) covers more than 90% of the irrigated area in the country. In this study we considered only DTW irrigation because it needs higher management than STW and LLP. The present study tried to analyze the past experiences and future potentials of co-operative organization for effective management of DTW irrigation. To measure the effectiveness of irrigation management the study considered some essentials, which are a) soundness of irrigation management system, b) appropriate water supply for better yield, c) equity in the distribution of water, d) sustainability and continuity in the irrigation system, and e) welfare of the people in the area. The specific objectives of the study were to i) make a review of the development of agricultural co-operative and its impact on irrigation development, ii) compare the co-operative managed irrigation system with private group managed irrigation system, iii) find out the impact of individual ownership of irrigation equipment on present land distribution structure, iv) analyze the development of alternative co-operative approach and its impact on effective irrigation management system, and v) try to develop some suggestions for the development of an co-operative organization, which can manage the DTW irrigation effectively and workable for community development. Chapter I deals the statement of the issues regarding irrigation management, related studies, purpose of the study and objectives.

　The review of development of agricultural co-operative and its impact on irrigation development is described in chapter II. It revealed that, the two-tier (village and thana level) co-operative namely Comilla model co-operative developed through pilot experimentation and research and maintaining linkages with appropriate local government agencies and government functionaries made positive contribution in adoption of new farm technologies like irrigation equipment, HYV (High Yielding Variety) seeds, fertilizer etc. and increased production in the late 1960s. But over time it was argued that relatively large landowners dominated the co-operative, therefore the future of co-operative as well as management of the irrigation equipment by co-operative organization became uncertain.

　Chapter III describes methodology and gives some idea about the characteristics of the survey areas. The study was conducted three field survey from 1999 to 2000 in seven villages under three Thana in the Comilla District. Primary and secondary data were used for analysis. Necessary official records and reports were also consulted. For analysis different statistical tools, graphs, t-test and growth model were used.

　Chapter IV gives a comparative study of two different management systems of DTW. The data were collected from two villages (one is co-operative managed-CM and other is private 4 shareholder managed-PM) by direct interview with the sample villagers (water users) under the command area, managers and owners of the DTW. Basic characteristics of the two villages were almost similar with the Comilla District. Similar characteristics were also found between the two DTWs. The comparison of two management systems showed that in the CM area all decisions and work related to irrigation were done with the participation of all water users, therefore a participatory management system was found in this area. On the contrary, in the PM area only shareholders did the all jobs and took decisions regarding irrigation. Water users have no right to give their opinion in this respect. They only come to one shareholder to pay their water charge. Therefore a non-participatory management system was found. The users reaction on existing management system was analyzed to find out users feeling about their management system. The results showed that almost 100 percent of the sampled farmers in the CM area responded that their existing management system was good. In the PM area only about 22 percent farmers responded similarly. In terms of getting water on time and sufficiently in the CM area again 100 percent farmers responded that they got water on time and sufficiently, as against only 17 percent in the PM area. Farmers in the two areas were asked about their water distribution system, if it was good, average or bad. The data showed that in the CM area maximum number of farmers answered in favor of good water distribution system. In the PM area only 15 percent farmers reported the same. The major cropping pattern Aus-Aman-Boro-Winter crop with intensity about 248 percent was found in the CM area but in the PM area, Aman-Boro-Winter crop was found as a major cropping pattern with intensity about 197 percent. The cultivation of three rice crops need planning, particularly the timely planting and harvesting of Boro rice. Timely growing of Boro rice basically depends on proper water supply. In the CM area farmers were getting water approximately 4 days after placing their demand whereas in the PM area it was approximately 20 days after. For this reason farmers in the PM area could not apply good cultivation plan, which was found in the CM area. Per acre yield of Boro rice was found about 19 percent more in the CM area than PM area. In case of per acre fertilizer use, minimum differences were found. Return from per acre Boro rice production was found 45 percent more in the CM area than PM area. About 31 percent less water charge was found in the CM area than PM area. Water charge was not much higher than the operation and management cost in the CM area but in the PM area water charge was higher than the operation and management cost. Therefore the income from the CM-DTW was found less than the PM-DTW. But in the CM area income from the operation of the irrigation equipment was pooled to develop different funds like DTW maintenance or replacement, welfare of the village households, etc. In the PM area the income was mainly invested for personal development of the shareholders. They did not make any fund for DTW. Therefore the replacement of the DTW would be difficult in future in this case they might be fall back to the rain-fed agriculture or traditional system. Therefore it was observed that the essentials for effective irrigation management can fulfill if water users are participate in the irrigation related works.

　Chapter V revealed the impact of individual ownership of DTW on present land distribution pattern. Three private managed DTWs from three villages were selected. All the owners (Total 17) and 75 farmers of different farm size category were asked separately from the three villages (25 from each). The land ownership structural scenario showed skewed distribution pattern of land in the country and in the study villages. A few households control quite a substantial amount of land but many of them do not cultivate the land by themselves. Maximum land rented by them was found under 50:50 share arrangements that was considered as the most exploitative tenure system. The most of the DTW owners were the large landowners and the percentages were 42.86-100. The results also showed that these owners had purchased a large area of land after buying the irrigation equipment, the range were 36-100 percent. Therefore they were accumulating more land by DTW business and enhanced inequalities in land holding structures. Investment of surplus income by different farm size categories showed that the large farmers invested 18.80 percent of total income for agricultural production and processing purposes but the medium and small farmers invested 79.20 and 88.00 percent. In case of DTW owners only 5 owners replied that they invested their surplus income for agricultural production and processing purposes.

　Chapter VI gives an analysis on future potentials of co-operative. For this, the study considered the new co-operative system in the country. Three societies were selected randomly. All of which were regenerated their activities by adjusting the new objectives of co-operative more than ten years before. The data were collected from the farmers and managers level. To develop a community-based bottom up co-operative the new principles of co-operative have developed in the year 1989. Under this the two-tier co-operatives regenerated their activities and developed as a new co-operative namely Comprehensive Village Development Co-operative (CVDC). The field level survey showed that, in the CVDC societies a good management structure is formed in which all categories of farmers can become the members of the executive committee, which minimizes the dominance of large farmers. Because of year-round work, weekly meetings were held regularly with the active participation of members. The annual growth rate of savings capital was positive, and per person capital was higher than the other co-operatives in the Comilla District. Profit from the different business projects was positive in the selected societies.

　Since irrigation equipment is considered a major business therefore it is operated profitably in all societies. Almost 100 percent farmers in all villages replied that they receive sufficient supply of irrigation water. Water charges were also found less than the current market price of the local area, and water charge collection was found good in all villages. Annual growth rates of command area and number of beneficiaries were found positive because of good irrigation facility. Farmers of this area have got different agricultural training, which helped to increase the skills in terms of cultivation and crop management. As a result, cropping intensity and production of HYV Boro rice is increased. Farmers of this area have increased their farm and non-farm income by increasing crop production and different small farm businesses with the help of the co-operative.

　Chapter VII attempts to summarize the major findings in the previous chapters and also stated some recommendations. This chapter also tried to show a co-operative framework that would work for the co-operative in the future as well as irrigation development in the country. In fact the irrigation equipment under the management of a co-operative is a cementing factor for bringing village households together. The co-operative is played the main role in the expansion of irrigation in the country before privatization and still now plays an important role in the irrigation sector even after privatization. Policy depends on the organization of co-operative for rural development and how this could survive and deliver goods to the villagers. Presently the CVDC societies have shown very successful results. However, this could not be considered very solid. Because, CVDC is still supervised and partially financing by the government. But if it considers the present market situation, at present there is arising competition in the market by various organizations. Therefore CVDC should compete with these organizations. For this CVDC can develop them as a community-based business organization. As a community-based business organization they can develop storage facilities of farm and non-farm products and make co-operative marketing center, workshop for repair and maintenance of agricultural machinery and irrigation equipments and agricultural equipment selling center. And the co-operative can develop education and training center for the member workers to manage the business successfully. Also primary co-operative can work with the government bodies to develop irrigation infrastructure. For this, the co-operative can make plan for design and construction of irrigation system and can give financial and physical support.

　To develop effective irrigation management special attention should be given. Corrective action is needed for this as it is generally observed that a few rich and middle farmers continue to given preferential access to irrigation facilities before and after privatization of DTW irrigation. In this case the participatory irrigation management systems would be considered. The organization of the water users and the individual group owners should bring to a same bargaining table for a reasonable water charge and fair supply of water.

　バングラデシュでは灌漑の発展をめざしていくつかの政策がとられてきた。しかし、 2002年の計画目標756万</SPAN>haに対して400万</SPAN>haの達成にすぎない。 需要に見合った食糧（米）の増産は未達成である。今日、小規模灌漑すなわちDTW（深井戸管灌漑）、STW （浅井戸管灌漑）およびLLP（低揚程ポンプ）はその国の灌漑面積の90%以上を占めている。本研究はDTWの 有効なマネージメントのための協同組合組織について過去の経験と将来の可能性について分析しようとするもの である。その有効性を測定するために本研究では次の五つの基準を設けた。①灌漑マネージメント・システムの 健全性、②高収量を可能にする適正な水の供給、③水の公平な分配、④灌漑システムの永続性、⑤地域住民の 福祉、である。本研究の目的は①農業協同組合の発展史を概観し、灌漑の発展に与えた影響を検討する、②協同 組合と私的グループによる灌漑マネージメント・システムを比較・検討する、③灌漑装置の民営化が今日の土地 分配構造に与えた影響を解明する、④新たな協同組合のアプローチとその有効な灌漑マネージメント・システム に与えた有効性を分析する、⑤DTWの有効なマネージメントと農村コミュニティーの発展を可能にする協同組合 組織のあり方について提言する、ことである。

　第一章ではこの分野の先行研究について総括し、本研究の目的と課題を明確にする。第二章では農協の 発展と灌漑に与えた影響を考察する。そこでは、二段階（村と郡）からなるクミラ・モデルの先導的試行に よって1960年代後半から新しい農業技術すなわち灌漑装置、高収量品種、肥料などが導入され、増収に大きく 貢献したこと、しかし、次第に協同組合を支配する大土地所有者が出現し、協同組合の将来が灌漑装置の マネージメントと共に不確かなものになったこと、が論じられる。

　第三章は方法論と調査対象地域の特性について述べられる。1999年から</SPAN>2000年に かけて3回の実態調査がクミラ県の3つの郡で7つの村を対象に実施された。その１次資料と２次資料および政府 の統計や報告書などが活用された。分析は図解、ｔ検定、成長モデルなど主として統計手法が用いられた。

　第四章では、二つの異なるDTWのマネージメント・システムについて比較研究を行なった。二つの村が対象で、 ひとつは協同組合経営（CM）、もうひとつは４人の私的所有者による経営（PM）について、それぞれ</SPA N>DTWの水の利用者、マネージャー、所有者から聴取り調査を行なった。二つの村の基本的な性格はクミラ 県の他の村々と同じで、二つのDTWについても同様である。この二つのシステムを比較した結果、CM地域では灌漑 に関する全ての決定と仕事は水の利用者全員の参画にもとづいてなされていた。それに対してPM地域ではDTWの 所有者のみであった。

　後者では水の利用者は何ら発言権がない。彼らは、水の利用料金を支払うためにのみ所有者の所に来る。従って 非参加型マネージメント・システムである。この二つのシステムについて利用者の反応を分析した結果、CMでは殆ど 100％の回答者がこのシステムを良しとしたが、PMではそう回答したものは22％のみであった。必要な時に十分水を 確保しえたか、の設問に「はい」と答えたのはCMでは100％、PMでは僅か</SPAN>17％であった。これら の給水システムの農民たちによる評価はCMの場合は大半が「可」、であった。主要な作付方式はCMでは 〈アオス―アマン―ボロ―冬作物〉で土地利用率（延べ作付面積／純作付面積×100）は248％、PMでは 〈アマン―ボロ―冬作物〉で197％であった。稲の三期作にはボロ稲の適期作付と収穫を必要とする。ボロ稲の生育に とって適切な水の供給が決定的に重要である。CM地域では農民たちは水の発注後４日で確保しているが</SPAN> PMでは20日を要している。そのためにPMではCMのような作付方式を導入できずにいる。１エーカー当りのボロ稲の収量は CMが</SPAN>PMより</SPAN>19%多い。肥料の使用量は両者で大差は見られず1エーカー当たり の粗収入はCMの方が</SPAN>45パーセント多い。水の利用料金はCMの方が</SPAN>PM より<SPAN>31パーセント安い。その料金はCMでは経営費にくらべてさほど高くないが、PMではかなり高い。 従ってDTWから得られる所得はCMの方が</SPAN>PMに比べて少ない。そしてCM地域ではそれらの所得は DTWの維持、更新のための基金や村全体の福祉のために共有される。一方、PMでは主としてDTW所有者たちの利益の ために投資される。彼らはDTWの基金づくりはしない。だからその更新は将来、困難となり、再び天水利用の伝統的な 農法に戻らざるをえなくなるであろう。有効な灌漑マネージメントにとって必要不可欠な要素は水の利用者による灌漑の 仕事への参画であることが明らかになった。

　第五章はDTWの個人所有が現在の土地配分パターンに与える影響を調査した。3つのPMによる</SPAN>DTW を三つの村から選んだ。DTWの所有者は17名全員、農民（水利用者）は３つの村から各25名、計75名を階層別に選んだ。 土地所有構造のシナリオはこの調査地域でも全国と同じく歪んだ土地配分パターンになっていた。少数の農家が土地の 大部分を支配し、その殆どは自ら耕作をしていない。彼らによって貸付けられた土地の小作料は収量の50%という 小作制度の最高の搾取度であった。DTWの所有者の大半は大土地所有者でその割合は42.86～100%であった。彼らは 灌漑装置の購入後、多くの土地を入手しており、その割合は36～100％に及んでいる。従って、彼らはDTWの事業に よって土地を集積し、土地所有の構造を不平等なものにしている。階層別の余剰所得投資は大規模農家では全所得の 18.80%が農業生産と加工のためであるが、中および小規模階層ではそれぞれ</SPAN>79.20%、88.00%で あった。DTWの所有者のうち5名のみが余剰所得を農業生産と加工に投資した、と答えている。

　第六章は協同組合の将来についてその可能性を分析する。新しい農村協同組合のシステムを考察するために三つの 組合が任意に選択された。それらは全て10年以上も前に新しい協同組合の目標にむかって自己革新しつつある。調査は 農民とマネージャーに対して行なわれた。地域社会に根ざした協同組合の発展をめざして1989年以降、新しい協同組合 の原則が開発された。それが<SPAN>CVDC（包括的農村発展協同組合）である。実態調査の結果、CVDC では全階層の農民が執行委員会のメンバーになることが出来、大規模農家の支配を最小にすべくマネージメントの構造 が工夫されている。年間を通して積極的な参画がみられた。貯金の年々の増加率は高く、一組合員当りのそれはクミラ 県の他の農協に比べて高い。種々の事業からの利益も同様である。灌漑装置は組合の主要事業のひとつなので全ての 組合が収益を確保している。全ての村で殆ど全ての農民が十分な水の供給を受けていると答えている。水の利用料金は その地域の市場価格よりも安く、その徴収も良好である。灌漑面積と受益者数は共に増加傾向にある。農民たちは種々の 農業研修を受け、耕作や作物栽培の技術を高めている。その結果、土地利用率と高収量品種のボロ米の生産が増加 している。彼らは協同組合の支援で農業と種々の小規模な事業によって農業および農外所得を増加させている。

　第七章はこれまでの考証を総括し、若干の提言を行なう。と同時に、バングラデシュの灌漑のみならず、協同組合 の将来に向けたフレーム・ワークの提示を試みる。協同組合のマネージメントのもとで灌漑装置は村人を結束するひとつ の接着剤である。その装置が民営化される以前から灌漑の普及にとって協同組合は重要な役割を担って来たし、今なお、 然り、である。農村の発展と村人の生活向上に必要な政策は協同組合の組織に依存している。現時点ではCVDCの組合 は大きな成果を上げている。しかし、それは固定的なものではない。何故なら</SPAN>CVDCは政府に よって監督され、一部財政援助を受けているからである。今日の市場経済の動向を考慮すれば、種々の組織との市場競争 の激化が予想される。従ってCVDCは競争力の強化が不可避である。そのためにCVDCはコミュニティーに根づいた 事業組織としての展開が必要である。具体的な課題としては農産物および非農産物の貯蔵施設や共販センター、農業 機械や灌漑装置の修理や維持のための工場、農業資材の供給センターの設置などである。さらに、それらの事業の マネージメントに必要な組合員の教育と訓練センターも必要である。と同時に、基礎組合は政府諸機関と共に灌漑の ためのインフラストラクチャーの整備に努めなければならない。そうすれば、政府諸機関は灌漑システムの構築の ために計画を立て、財政的かつ人的支援が可能になる。

　有効な灌漑マネージメントの発展には特別の注意が必要である。何故なら、少数の中富農層 が</SPAN>DTWの民営化以前から以降にかけて灌漑施設を優先的に獲得する傾向が一般的に見られる からである。CVDCでは参加型灌漑マネージメント・システムが考慮されている。水の利用者組織と個人所有者グループ は適正な水の利用料金と公正な水の供給について同じ売買取引のテーブルにつかなくてはならない。