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INDUS DELTA, PAKISTAN: Economic Costs of Reduction in Freshwater Flows

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INDUS DELTA, PAKISTAN: Economic Costs of Reduction in Freshwater Flows water allocationdecisions. factored intoriverbasinplanning,or benefits of water-basedecosystemsarerarely economic users ofwater.Yettheeconomic schemes, Pakistan’secosystems,too,are hydropower dams, reservoirs,irrigationand as water tolarge-scale,commercialusessuch imperative that favours theallocationof Contrary tothedominantdevelopment economically norecologicallyoptimal. decisions beingmadethatareneither needs has oftenledtowaterallocation Failure torecognisedownstreamecosystem heavily byupstreamwaterabstraction. end of rivers,havebeenimpactedmost the at lie and marineregions,becausethey Coastal ecosystems. needs ofdownstream many cases, left insufficientflowtomeetthe of large volumesofwaterfromrivershas,in particular there isconcernthattheabstraction exacting a heavytollontheenvironment.In This impressive irrigationsystemis,however, world. the irrigated torain-fedlandratioin highest the farmland, affordingPakistan system feedsmorethan15millionhectaresof than 1.65 million km(IRIN2001).The more watercourses witharunninglengthof 89,000 conveyance lengthof57,000km,and head works, 43maincanalswitha or barrages 19 three majorstoragereservoirs, comprises Pakistan’s vastirrigationnetwork Pakistan Water-based developmentsin flows reduction infreshwater economic costsof INDUS DELTA,PAKISTAN: VALUATION #5:May2003 CASE STUDIESINWETLAND Integrating Wetland Economic Values into River Basin Management Managing freshwater flows in the The economic costs and losses arising from Indus River such omissions can be immense, and often The Indus River has a total length of more irreversible, impacting on some of the most than 3,000 km and a drainage area of some fragile ecosystems and the poorest and most 950,000 km2. Almost 90% of the water in the vulnerable human groups. This case study upper portion of the river basin comes from describes the economic costs that have glaciers located in the Himalaya and occurred as a result of inadequate freshwater Karakoram mountain ranges, which border allocation to the Indus Delta in Pakistan. China, Pakistan and India, and the Hindu Especially, it focuses on the crippling Kush, which borders Pakistan and Afghanistan. environmental economic costs that upstream The Indus travels southwards across Punjab water allocation decisions have incurred to and Sindh Provinces in Pakistan before poor local populations, manifested through entering the Arabian Sea through a delta close declining agricultural yields and fisheries to the border with India. production. Figure 1: The Indus Delta The Indus Delta is a typical fan-shaped delta, at this level the amount of freshwater reaching built up by the discharge of large quantities of the Delta was argued to be insufficient to silt washed down from upland and mountain maintain healthy natural ecosystems, and had areas. The present Delta covers an area of resulted in severe saltwater intrusion and about 600,000 hectares and is characterised by salinisation. With the existing reduction in 17 major creeks and innumerable minor creeks, flow, downstream Sindh Province already mud flats and fringing mangroves (Meynell and claims it is short of the minimum 12 billion m3 Qureshi 1993). The mangrove ecosystem of the of water needed to maintain the Delta. Indus Delta is perhaps unique in being the largest area of arid climate mangroves in the The economic significance of the world. As annual rainfall is so low in the region, mangroves are almost wholly Indus Delta dependent upon freshwater discharges from Loss of freshwater flow, and consequent the river, supplemented by a small quantity of saltwater intrusion, has had devastating effects run-off and effluents from Karachi. on the ecology and human economy of the Indus Delta. Land in the area has become The total available freshwater flow in the Indus unsuitable for agriculture, and potable water is about 180 billion m3, carrying with it some sources have become very scarce or have 400 million tonnes of silt (Meynell and Qureshi disappeared altogether. In Thatta, a 1993). Over the last 60 years a series of dams, predominantly agricultural District in Sindh barrages and irrigation schemes have been built Province which is situated where the Indus in upstream parts of the River Indus. Today, it river flows into the Arabian Sea, almost a third is estimated that up to 60% of the Indus water of land has been affected by saltwater is used to feed Pakistan’s irrigation networks, intrusion. It is estimated that up to 0.5 million and that the Indus watershed irrigates up to hectares of fertile land in Thatta and adjoining 80% of Pakistan’s farmland (Iftikhar 2002). areas (IRIN 2001), or about 12% of total There has for some time been a high level of cultivated area in the entire Province controversy surrounding the allocation of the (Government of Pakistan 2001), is now waters of the Indus River, in particular between affected by sea water intrusion. As well as crop competing uses in different Provinces. losses, this has resulted in severe damage to Recurrent disputes over water usage led the livestock through rangeland depletion, shortage government to set in place the Indus Water of fodder, pasture and watering areas, and a Accord in 1991, which apportioned the use of resulting mass migration of both livestock and the river’s water between the four provinces of human populations out of the area. Pakistan. It also recognised − for the first time − the need to allow some freshwater discharge The human population in and around into the delta to safeguard the ecosystem, mangrove forests on the coast of Pakistan is specifying a minimum flow of 12 billion m3. In estimated to total 1.2 million people, nearly 1994, because of drought and water shortages, 900,000 of whom reside in the Indus Delta Punjab Province however demanded and got a (Salman 2002). Of these, a predominantly rural break from the 1991 Water Accord and a population of more than 135,000 depend on subsequent higher reallocation based on mangrove resources for their livelihoods (Shah historical use. 1998). Reductions in freshwater inflows have had tangible impacts on mangrove ecology, and As a result of upstream water abstraction, on the fish populations that rely on them for mainly for irrigation, by the time the Indus breeding and habitat. At least three quarters of reaches the Kotri Barrage (some two thirds of the Delta’s rural population depend, directly or the way into Sindh Province, or 200 km from indirectly, on fishing as their main source of the Arabian Sea), there is inadequate flow to income, and most of Pakistan’s commercial maintain the natural ecosystems of the Indus marine fishery operates in and around the Delta. The annual flow reaching the Delta mangrove creeks on the coast of Sindh before the 1994 break from the Water Accord Province. A large proportion of fish and was less than 43 billion m3, and quantities of crustaceans spend at least part of their life cycle silt discharged estimated to be 100 million in the mangroves, or depend on food webs tonnes/year (Meynell and Qureshi 1993). Even originating there (Meynell and Qureshi 1993). The annual value of catch from mangrove- population of some 155,000 people. This area dependent fish species in the Indus Delta is has been most heavily impacted by seawater estimated at around $20 million. Shrimps are intrusion in the Indus Delta. Valuation relied also particularly important, with a domestic primarily on data collected at the Village, value of $70 million and an export value of Taluka and District levels. Primary data about one and a half times this figure, and the collection, through field visits, involved surveys export of mud crabs contributes an additional of farming and fishing communities, interviews $3 million to the regional economy (Mahmood with government line departments, and and Ali undated). consultations with other public sector and non- governmental organisations. Where data Over 60 percent of the rural population also already existed in the form of statistics from use the Delta’s mangroves as their major Federal and Provincial Government source of domestic fuel, estimated to account publications, these comprised the bulk of for around 18,000 tonnes of firewood (Khalil secondary sources. The study entailed 1999) which is worth up to $460,000 a year collecting data on the ecological impact of sea (Mahmood and Ali undated). Mangroves are intrusion and economic data on agricultural also used by coastal villagers as fodder for and fisheries products, and establishing a link domestic animals. In addition to cattle, sheep between reduced freshwater flows, saltwater and goats kept permanently in the Delta, it has intrusion, and loss of household production. been estimated that at certain times of the year about 16,000 camels are herded into the Using valuation to show the mangroves (Khalil 1999, Meynell and Qureshi 1993). In total, the Indus Delta’s natural economic benefits of allocating ecosystems are thought to contribute about water to ecosystems 67,000 tonnes of leaves and 20,000 tonnes of Analysis of the data collected during the study grasses as livestock pasture and fodder each showed that reduced freshwater flows, and year, together worth up to $1.35 million consequent ecosystem degradation, had (Mahmood and Ali undated). impacted heavily on local livelihoods and economic production in the Indus Delta area. Valuing the economic costs of Both aggregate crop production and fish catch saltwater intrusion had declined steadily as salinity had increased. The three Talukas or 30,000 households The
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