INTEGRATED WATER RESOURCES MANAGEMENT Lectures – 5 & 6.

INTEGRATED WATER RESOURCES MANAGEMENT Lectures – 5 & 6

Miscellaneous definitions/concepts  Goals:  Objectives:  Strategies:  Criteria:  Indicators:  Scenarios:  Constraints: Measures performance of formulated strategies in terms of stated objectives Broad, qualitative statements about what to be achieved or what problem is to be solved What should be achieved to reach a goal Individual or combination of measures identified to accomplish objectives (infrastructural, management instrument, institutional arrangements) Criteria translated into indicators; represent the behavior or performance of the systems under consideration in more general terms Changes beyond the control of managers Pose limitations to possible measures and solutions

 With and Without Project  Triggers - not same as ‘now’ and ‘future’ or ‘before’ and ‘after’ - ‘Problem’ or an ‘undesirable event’ - meeting unsatisfied demands - developing under-utilized resources - achieving national development objectives -other planning efforts (landuse, energy or agricultural development)

Conceptual Framework for Analysis: Planning Steps Step-1: Analysis of problems and identification of possible measures Step-2: Specification of objectives and criteria Step-3: Delineation of analysis conditions Step-4: Analysis of possible measures and promising strategies Step-5: Implementation assessment of selected strategies Step-6: Evaluation of selected strategies Step-7: Presentation of results

Step-3: Delineation of analysis conditions Step-2: Specification of objectives and criteria Step-1: Analysis of problems and identification of possible measures  Identify all possible present and future problems  Quantify the problems; first screening of possible measures with respect to their costs and effectiveness. Criteria should be: substantial, factual, plausible, obtainable, independent Can be of following two broad types: qualitative:good/bad, high/low, positive/negative quantitative: physical or economic quantities Valued: monetary terms (NPV, IRR) non-valued: e.g. no of people affected, people displaced) *Scenarios*Time horizons*Areal boundaries *Discount rate /base year*Hyd. & meteorol. conditions

Step-5: Implementation assessment of selected strategies Formulating strategies Specifying cases for analysis Step-4: Analysis of possible measures and promising strategies possible under existing institutional arrangements? capable to implement strategy? conflicts of interests? any constraints in financing and staffing?)

Step-5: Implementation assessment of selected strategies (i)Management tasks (possible under existing institutional arrangements?) (ii) Responsible agencies and corresponding institutional linkages (capable to implement strategy?) (iii) Existing policy intentions (conflicts of interests?) (iv) Financing and staffing (any constraints?)

Step-6: Evaluation of selected strategies Consists of two parts: Assessment (and comparison) of effects or impacts of all strategies in terms of criteria formulated - objective process - sound scientific analysis and judgment - models and methods of physical and social sciences. Arrive at a ranking of proposed strategies (indications of relative importance) - subjective process - ‘value’ judgment based on moral, cultural and political factors - analytical tools/techniques

Step-6: Evaluation of selected strategies Ranking procedure includes: Cost-effectiveness analysis (CEA) Benefit-cost analysis (BCA) Multi-criteria analysis (MCA)

Step-6: Evaluation of selected strategies CEA compare costs of alternative strategies which comply with targets When applied? - objective can not be valued - long-term environmental or sustainability targets are set as fixed objectives (constraints) - most economic approach is sought

Step-6: Evaluation of selected strategies BCA All (social and economic) direct and indirect benefit and cost translated into monetary units (NPV, IRR, B/C ratio) by different evaluation techniques Benefits are measured (ideally) in terms of people’s willingness to pay; costs are measured in terms of “opportunity cost” of the value of benefits forgone Main technique for assessing economic efficiency Examples of Costs - project preparation, implementation, compensation & mitigation, administrative Examples of Benefits - higher (or lower) economic activities, changes in flood damage, safety, public health, living conditions, environment, historical and cultural systems

Step-6: Evaluation of selected strategies BCA

Step-6: Evaluation of selected strategies BCA IRR (i) ---

Step-6: Evaluation of selected strategies Limitations of BCA  Concept of benefits depends on a demonstrated willingness to pay – also depends on ability to pay - constraint of income levels  ignores distributional effects (aim: maximize net benefits)

Step-6: Evaluation of selected strategies Limitations of BCA  practice of discounting has limitations oPV of B & C can be a small fraction of future value ohigh ‘i’ – favors strategies/projects with a quick return olow ‘i’ – favors strategies/projects with long term benefits oMany actions –- short term economic benefit and deferred costs to future generations (e.g. damaged or rehabilitation costs of degraded farmlands, fish habitats and polluted water ways) oconflict with objective of “sustainability”  uncertainty in valuing social and environmental effects (especially ecosystem)

Step-6: Evaluation of selected strategies

Step-6: Evaluation of selected strategies MCA  Not to be considered as an alternative to political decision making process

Step-6: Evaluation of selected strategies MCA  Not to be considered as an alternative to political decision making process  Many different methods and techniques

Step-6: Evaluation of selected strategies MCA  Not to be considered as an alternative to political decision making process  Many different methods and techniques  Often different methods used to compare and test sensitivity of method

Step-6: Evaluation of selected strategies MCA  Not to be considered as an alternative to political decision making process  Many different methods and techniques  Often different methods used to compare and test sensitivity of method  Ideal platform for participatory planning, involving stakeholders, technical experts and analysts

Step-6: Evaluation of selected strategies MCA  Not to be considered as an alternative to political decision making process  Many different methods and techniques  Often different methods used to compare and test sensitivity of method  Ideal platform for participatory planning, involving stakeholders, technical experts and analysts  All effects need not be translated into a common unit of value or significance

Step-6: Evaluation of selected strategies Scoring (performance with respect to criteria) Standardization (reduce scores to same type of unit) Weights (relative importance of criteria) %, $, fractions, Volume Good/bad/fair, Yes/no, ++/+/0/-/-- Etc. Steps Determine actual scores with respect to criteria Determine the standardized scores Determine the weights of the criteria Select an MCA (arithmetic) technique Present the results of ranking procedures Perform a sensitivity analysis on method

Step-6: Evaluation of selected strategies CriteriaAlternative strategies ABC Investment costs (M$)706540 Irrigated area (ha)20,00025,00018,000 GWL draw-down (m)1.09.015.0 Marketing opportunitiesgoodbadFair People displaced500010002000 Environmental deteriorationyesnoUncer. Flood security (T yrs)100 50 Scorecard (project – exploitation of SW in combination with GW)

Step-6: Evaluation of selected strategies Beware of double counting Highest score is always not the best!!! Different scorecards for different scenarios Different scorecards for different time horizons Different scorecards for different clusters Screen out infeasible strategies

Step-6: Evaluation of selected strategies CriteriaAlternative strategies ABC Investment costs (M$)706540 Irrigated area (ha)20,00025,00018,000 GWL draw-down (m)1.09.015.0 Marketing opportunitiesgoodbadFair People displaced500010002000 Environmental deteriorationyesnoUncer. Flood security (T yrs)100 50 Scorecard with different units Methods of standardization (K – alternative; J – criterion) 1. Best strategy scores 1; relative ranking not influenced by other strategies 2. Best strategy scores 1 (or 100); worst strategy scores 0 3. Standardized scores add up to one

Step-6: Evaluation of selected strategies Criteria Alternative strategies ABC Investment costs (M$)706540 Irrigated area (ha)20,00025,00018,000 GWL draw-down (m)1.09.015.0 Marketing opportunitiesgoodbadFair People displaced500010002000 Environmental deteriorationyesnoUncer. Flood security (T yrs)100 50 Criteria Alternative strategies ABC Investment costs (M$)00.171 Irrigated area (ha)0.2910 GWL draw-down (m)10.430 Marketing opportunities100.5 People displaced010.75 Environmental deterioration010.75 Flood security (T yrs)110 Scorecard with different units Standardized scores

Step-6: Evaluation of selected strategies Criteria Alternative strategies ABC Investment costs (M$)706540 Irrigated area (ha)20,00025,00018,000 GWL draw-down (m)1.09.015.0 Marketing opportunitiesgoodbadFair People displaced500010002000 Environmental deteriorationyesnoUncer. Flood security (T yrs)100 50 Criteria Weight coeff. Alternative strategies ABC Investment costs (M$)200.171 Irrigated area (ha)10.2910 GWL draw-down (m)110.430 Marketing opportunities1100.5 People displaced1010.75 Environmental deterioration2010.75 Flood security (T yrs)1110 Total score3.295.774.75 Scorecard with different units Weighted sum

Methods of determining weights Giving a rating to each criterion on an appropriate scale such as 0-10 Placing the criteria in a priority order (e.g. most important = 1; 2 nd most important = 2; etc.); normalizing them by applying “expected value method” Pair-wise comparisons of criteria, with numerical scores indicating importance with which each criterion meets the overall planning objective relative to some other criterion.

Remarks Again – highest score is not always the best Number of strategies may influence the standardized score, and nay consequently influence the ranking of strategies (first screen out weak strategies) Standardized method chosen influences standardized score and may consequently influence ranking of strategies With standardization, ordinal (qualitative) --- cardinal (quantitative) scores; need careful attention!!

Sensitivity analysis Show how the strategies perform and consequently are ranked under different assumptions for variables, parameters and evaluation method Ask “what if” about the effects of scores and weights used in an MCA Whether some options are clearly superior or inferior to others (sometimes regardless of the importance of weights applied).

A River Basin Planning Project Project: Allocation of surface water to two main users: (i)an agricultural area, and (ii) a city while the fish production in a downstream lake depends heavily on water quality

INTEGRATED ENVIRONMENTAL MANAGEMENT A Case Study on Shrimp-paddy Land Use Strategies in the Southwest of Bangladesh EGIS Technical Note 19 EGIS II Alternating crops between shrimp and paddy is widely practiced. In the northern part, the Boro- Golda crop cycle is becoming common In the southern part where salinity is higher, the Bagda-Aman crop cycle is more common. Bagda harvesting overlaps with Aman plantation giving rise to land use and therefore social conflicts. There is no overlap between Boro and Golda cultivation seasons.

Strategies Bring all suitable land under shrimp cultivation Bring all suitable land under paddy production Allocate land to an appropriate crop regime according to its suitability Goal: ‘optimize use of land resources for shrimp-paddy cultivation in the study area’

ObjectiveCriteriaIndicator Increase economic growthNational economyRegional income Foreign currency earning Economic efficiencyEmployment Net economic return Improve social well-beingQuality of lifeNutrition Sanitation Education Housing Public health Access to opportunitiesUnskilled job opportunities Female work opportunities Access to resourcesAccess to common properties Access to small holdings Protect environmentEcological integrityAquatic bio-diversity Terrestrial bio-diversity Mangrove bio-diversity Physical qualitySoil condition Groundwater salinity

Likely scenarios:  Economic scenario: Export price of shrimp may fall making paddy production attractive once again;  Climate change scenario: Rise in sea level will push the salinity front inwards making Bagda production profitable in more areas;  Water resources management scenario: Likely increase in the Gorai flow will push salinity front downstream making Golda/paddy farming profitable in more areas. The value of indicators depends, directly or indirectly, on the different land uses under different salinity regimes according to a particular land use strategy. Relative importance was attached to each type of land use under a salinity regime through the pair-wise comparison technique.

Max Shrimp is an economically attractive strategy. From a social point of view, however, the Max Paddy strategy is superior.

Environmentally, Balanced Land Use is better than the other two strategies. For a set of representative weights assigned to economic, social and environmental objectives, the Max Shrimp is the preferred strategy in the study area.

The rankings do not change with an increasing flow through the Gorai River. However, increasing flow through Gorai would have a better impact on environmental aspects compared to the economic and social aspects

The Max Shrimp strategy in the study area comes out better because of its emphasis on Golda cultivation in the fresh water zone. Previously, all shrimp cultivation was based on Bagda cultivation, which is economically, socially and environmentally not as attractive as Golda cultivation. Golda cultivation is a recent phenomenon in the study area and has less social and environmental impact than Bagda cultivation. Table 8.13 shows the change in values if the Max-Shrimp strategy is based on only Bagda cultivation instead of a mix of Golda and Bagda. The performance of Max-Shrimp strategy is not satisfactory. With an increasing Gorai flow, which favors paddy production, it is only as good as the Max-Paddy strategy

Course Outline  Planning fundamentals and processes Management cycle Conceptual framework of analysis (planning steps) Strategies, criteria, indicators  Multi-criteria analysis Concept Score card Standardization  Sustainable development Definition Different approaches of evaluation Natural capital theory Indicators  Sectoral demands and resource allocation Economic dimensions of water management Demand of water in different sectors of Bangladesh Water allocation mechanisms (principles and examples)  Management of water demand and use Economic instruments Social instruments Institutional/regulatory instruments  Institutional aspects and people’s participation

Sectoral demand Economic dimensions of water management Demand management Economic instruments Social instruments Institutional/regulatory instruments Assessing demand

Monsoon Season Demands  In general, water shortages do not occur during the monsoon season from June to October. (demand is only a small fraction of supply) PET ~ 0.56m Rainfall ~ 1.8m inflows > 10m  In early part of monsoon, rainfall can be variable (significant to farmers who plant aman at this time; supplementary irrigation is practiced by few)

Demands fall into two basic groups Consumptive: those that consume water, essentially by evaporation (including ET) Non-consumptive: those that need water, but do not consume it. ET from vegetation is a consumptive use but percolation losses that return to the groundwater reservoir are not, because the water returns to the resource pool. Whether a demand is consumptive or not also depends on the location and the quality of any return flow. Any flow allocated for navigation may not be consumptive provided it can be used for other purposes before it reaches the sea, such as being used to control saline intrusion.

Dry Season Water Demands Consumptive demands (44% of total) o evaporation from forests, water bodies, charland, urban and rural environments (9% of total) o rainfed and irrigated agriculture (32% of total) o water supply and sanitation (3% of total) In-stream demands (56% of total) o Salinity and pollution control o Navigation o Fisheries.

1.Water Supply and sanitation (given highest priority in NWPo) Have low consumptive demands (3% of total demand) but are ascribed the highest priority under the NWPo. Water for domestic use is a basic human need, while commerce and industry are so important to Bangladesh that they should not be constrained unnecessarily by water availability.

1.Water Supply and sanitation (given highest priority in NWPo) 1.1 Domestic demand Domestic demand based upon estimated populations, standards of living and per capita consumption NWMP estimates for average consumption: Rural – 102 lpcd Urban – 119 lpcd SMA - 139 lpcd NWMP estimates for return flow: Domestic – 50% 1.2 Commercial and industrial demands Good data is not available; Industries tend to use own boreholes. Future demand estimation difficult; no industrial and land use policies. WB data: commercial – 8-11% of total supply industrial - 10–15% of total supply NWMP estimates: commercial demand - 10% of domestic urban demand industrial demand - 15% of domestic urban demand. Return flow: 75%

1.Water Supply and sanitation (given highest priority in NWPo) Source meeting demand SMAs - 50% of demand from SW; 50% from GW. Other areas - from GW

1.Water Supply and sanitation Domestic, Commercial and Industrial Demands Statistical Metropolitan Areas (SMA), namely Dhaka, Chittagong, Khulna and Rajshahi.

1.Water Supply and sanitation Domestic, Commercial and Industrial Demands

1.Water Supply and sanitation (given highest priority in NWPo) Demand also depends on water accessibility and quality of service Mondal (2005): NWMP figures are over-estimated Rural – 25 lpcd(NWMP – 102 lpcd) Urban – 110 lpcd(NWMP – 119 lpcd) (water pumped to the households; many activities (bathing,laundry, etc) undertaken at ponds outside the households) Mondal (2005) on return flow: Rural – 25%(NWMP – 50%) Urban 30%(NWMP – 50%) Commercial & Industrial – 50%(NWMP – 75%) (Much of the discharge into rivers are fugitive, unless utilized within 2-3 days)

Evaporation (including ET) takes place from all land types and needs to be accounted for in any assessment of resources and demands. The demand is estimated by multiplying the area of the surface for each land type by potential evapotranspiration ETo and a crop coefficient Kc. 2. Environmental, Fisheries and Forestry Evaporative Demand (not covered by agriculture) The gross evaporation is reduced by dry season rainfall (average rainfall is subtracted to assess net evaporative losses). Each land type is associated with a dominant nature of use, classified as environment, forestry and fisheries. Since the area of the land type has been estimated for each District, the analysis permits the evaporation losses to be associated with these three uses, and they form the demand by that use. regional non-agricultural evaporative demands is calculated on a month- by-month, Thana-by-Thana evaluation for each land type

2. Environmental, Fisheries and Forestry Evaporative Demand (not covered by agriculture)

2.Environmental, Fisheries and Forestry Evaporative Demand (not covered by agriculture) (average) 2.1 Environmental evaporative demands From rivers, urban (e.g. parks, gardens, bare soil, leaks in water distribution and sewerage systems), rural (sullage water, trees, bamboo clumps, small gardens, veg. plots, grass/scrubs) and other land types (e.g. charlands, brickfields). 2.2 Fisheries evaporative demands Under natural conditions, evaporative losses are normal and no additional water is needed to compensate for them. Problems arise when farmers drain the water either for irrigation of adjacent lands or to grow crops in the bed of standing water body itself. 2.3 Forestry evaporative demands Forest trees will abstract water from perched water tables, lower water tables and irrigation returns.

2. Environmental, Fisheries and Forestry Evaporative Demand (not covered by agriculture)

highest overall consumptive demand Effort has been into intensification of agriculture by promotion of dry season cropping through irrigation. The NWPo - a lower priority in future to water for agriculture compared to domestic, municipal, and non-consumptive uses. 3. Agricultural Demand The agricultural land type can be considered as: - Rainfed- Fallow- Irrigated Actual ET is estimated as: total demand by summing up crop water requirements for all crops. Effective rainfall GW irrigation needs are based on actual ET less average rainfall SW irrigation needs are based on actual ET less dependable rainfall. RECAP

Cropping patterns Records of crop patterns (area under each crop), crop sequences (which crop follows which) and planting/harvesting dates are poor and projections are very uncertain. 3. Agricultural Demand Cropping patterns depend on - Government policies - markets for irrigated crops - costs of irrigation equipment, water and other inputs (All subject to influences far beyond the control of WR planners) NWMP assumption - demands for increased production will increase pressure on farmers to obtain the maximum value from their land by introducing innovations in cropping and irrigation technologies; this will ultimately lead to continuous cropping in the dry season. - all land that could be irrigated is irrigated.

Crop coefficients For commonly grown crops, average Kc: Onion - 0.9Vegetable - 1.0Rice - 1.1 Future dry season patterns are likely to continue to be dominated by rice and to be followed or preceded by another crop. 3. Agricultural Demand On irrigated land -- an effective Kc of 1.1 for rice throughout the growing season -- an effective Kc of 1.05 when rice is combined with other crops On rainfed land, the Kc (for wheat, pulses and oilseeds, and vegetable later in the season) will be lower. On fallow land, most dry-season rainfall is evaporated, as is residual soil moisture and water drawn up by capillary action.

Irrigation efficiency Calculation of irrigation efficiency is meaningful for individual farmers, plantations and estates, but much less so for water system as a whole. In Bangladesh, few losses return to the main SW system. Most losses return to GW reservoir, refilling the upper aquifer and slowly lower aquifer over a period measured in days rather than months. Water then becomes available again for irrigation, water supply and trees and overall demands for these uses are correspondingly reduced. In an open system, where some of the return flow escapes to rivers, an allowance for < 100% efficiency must be made, particularly with SW irrigation. 3. Agricultural Demand NWMPP assumes 100% efficiency for SW and GW irrigation in areas where GW is usable, and 75% for SW irrigation in areas where it is not.

3. Agricultural Demand

4.In-stream demands (salinity control, navigation, fisheries, environment) Needs from various sources are not additive; need to determine the largest need in each river system, so that it can if possible be met. Any excess of flows over in-stream needs can be abstracted and used for irrigation wherever this is economically viable. NWPo makes clear that the priority lies with meeting in- stream needs before abstraction, other than that needed for water supply.

4.1 Salinity control Total minimum water requirements for salinity control are estimated as:  2000m³/s in the Lower Meghna  1000m³/s is through the SC region (Arial khan & Tetulia channels)  250m³/s through the Gorai for the SW region  150m³/s for other outflows in the SW region  56m³/s for the SE region  36m³/s for the EH region.

4.2 Navigation 4. In-stream demands Many are in tidal area & little affected by freshwater flow Class-I: from B. Bazar to Dhaka, Chandpur, Ilsaghat and from there to chittagong and Khulna Class-II: Chandour to Indian border in Assam, Bhairab to Sunamganj and Chhatak, Khulna to Calcutta and around Tetulia channel. Class-III: Aprt from Bhairab to Indian border (Kushiyara), Chittagong to Kaptai dam (karnaphuli), and short lengths around Dhaka and lower Atrai, all are in SW and SC regions Class-IV: The Ganges, Atrai and Old Brahmaputra (upto Mymensingh)

4.2 Navigation 4. In-stream demands How to maintain navigability:  Dredging at critical points  Level control to maintain the minimum depths with structures  Maintenance of flow

4.3 Fisheries (for flowing water) The minimum dry season water requirements for fisheries in rivers are in the form of pools of water for refuges. However, from April onwards through the monsoon season there is a need for flowing water along the migratory routes with a depth of over 1m. These routes are of two types: (i) those to upstream spawning areas (rivers which have historically had adequate flow); (ii) those connecting rivers to waterbodies and flood plains. In-stream needs for fisheries concern only the routes to upstream spawning areas. The minimum flows necessary to maintain the target depths in individual rivers will depend on the river widths. The required flows are similar to those required for navigation. 4. In-stream demands In general, it may be assumed that if navigation depths are maintained, fisheries needs will be satisfied.

4.4 Environment Some flows are normally set aside to ensure minimum flows in the river system. Needed to provide dilution of effluents from sewage treatment works, untreated effluents and for maintenance of aquatic life. In case of seasonal rivers, aquatic life is adapted to little or no flow in the dry season; hence little justification in increasing flows. NWMPP approach: maintain up to 40% of flows in-stream to meet environmental needs 4. In-stream demands

4.4 Environment 4. In-stream demands

4.5 Pollution control Aquatic environment is under great pressure from industrial and urban waste water pollution. Treatment works need to be built and sited with disposal of effluent in mind. Although rivers are capable naturally of reducing their BOD to a limited extent, it is poor use of limited resources to reserve flows in rivers to meet effluent dilution needs, which are often as high as 30:1. Initial identification of pollution ‘hot-spots’ for which it may be necessary to allocate flow to improve water quality. 4. In-stream demands

INTEGRATED WATER RESOURCES MANAGEMENT Lectures – 5 & 6.

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INTEGRATED WATER RESOURCES MANAGEMENT Lectures – 5 & 6.

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