Irrigation projects can have far-reaching, damaging ecological impact. The government must pay more than lip service to environmental concerns.
The Government of Nepal, with financial and technical assistance from the Asian Development Bank, began to plan the East Rapti Irrigation Project (ERIP) in the mid-1980s, showing little concern over how the project might affect the environment of the area. The feasibility report does not even mention the world-renowned Royal Chitwan National Park, whose northern boundary is the Rapti river. The ADB’s appraisal report of 1986 states blandly that “ERIP…is not expected to have significant negative environmental impact.”
ERIP is a large-scale surface irrigation project, which, when completed, will provide irrigation facilities to 9500 hectares of land in the eastern Chitwan Valley. The planners have suggested building a low diversion weir across the Rapti. The site of the permanent intake structure is actually inside the park. The designs of the weir and the channel are almost complete, and the project is awaiting final approval.
More than 40 species of mammals, 49 species of reptiles and amphibians, 113 species of fish, and 489 species of resident and migratory birds are found within the 93,200-hectare park area. The sanctuary has been recognised as a World Heritage Site for its biological diversity and pristine representation of the Churia Valley/Inner Tarai environment. Some notable endangered species found here include the one-horned rhinoceros, tiger, gharial, gaur and the Gangetic dolphin. The wetlands formed by three major rivers, of which the Rapti is one, provide a habitat for unique species, including the extremely vulnerable mugger crocodile.
Implementation of ERIP is likely to have dire consequences on the park ecosystem. Some of these will be easily identifiable and therefore correctable; other impact can be indirect but disastrous in the long term.
ERIP planners hope to expand irrigation of winter and spring paddy crops by diverting the Rapti flow mostly during the winter and spring months, which is when the river is at its lowest. Wildlife that specifically depend on wetlands would suffer significantly from this change. The reduced flow of water would disrupt the habitat for resident populations of gharial, mugger and tortoise, up to about 20 km downstream from the dam site. This stretch of water from Sauraha to Kasara is especially important for muggers, which need a constant flow of deep water all year around for survival. The irregularity in the water flow could disrupt access to nesting sites and flooding could destroy the nests and eggs. Similarly, the increased discharge of agricultural effluents could be lethal to the reptile and fish species.
Some local fishermen fear that the decrease in the volume of Rapti water, particularly during spring, will directly affect their fish catch. The most abundant fish species, Punctius, Barilius, and Aspidoparia, which will be affected by this change, also constitute important diets for otter, fishing cat, gharial, mugger, tortoise, fish-eating birds, besides the subsistence fisher-folk of the Rapti. Other prized fishes are also likely to dwindle in number. The ERIP planners have made provisions for a fish-way, but this is not enough, since water depth is also vital.
The endangered species which will be affected by the decline in fish will include birds such as the Fishing Eagle, Fish Owl, Osprey and Stork. Almost all the 160 wintering birds recorded in Chitwan, including over 20 waterfowl species, about 30 birds of prey and 16 waders, are likely to be affected by the reduced volume of the Rapti.
GRASS AND TOURISTS
Chitwan’s floodplain of kans grass (Saccharum spontaneum) provides one of the quality habitats of the park, providing ideal forage for wild herbivores like the rhinoceros. The floodplains and riverine forests together support a richness in wildlife that is comparable to that of sanctuaries in East Africa.
The maintenance of Chitwan’s forests depends upon the support of the local people, who rely upon the park for steady supply of grass. Every year, more than 60,000 people participate in the 15-day grass-cutting season, bringing out 11,000 tons of grass products. If the reduced water table in the floodplains affects the growth of kans grass, the rhinoceros and other herbivores will be in trouble and the park would also be less useful for the local people.
The tourist industry in the eastern end of the park could also be hurt, since ERIP could hamper eco-tourism activities like canoe rides and bird watching. In 1989, an estimated 19,000 tourists visited the national park, generating a gross income amounting to one million US dollars. The Park supports a fulltime staff of 565 employees and an equal number of seasonal staff.
IS ERIP NECESSARY?
Does Nepal need ERIP? The answer will depend upon how much importance is given to environmental issues when the final decision is made.
There is no basis, under existing law, on which to stop ERIP. Even the National Parks and Wildlife Conservation Act (2029) is not strong enough. Its article which prohibits diversion of water from any river flowing into the national park can easily be overruled by the government. Says B.N. Upreti, Director-General of the Department of National Parks and Wildlife Conservation: “Our Department’s history shows that we have always lost in all major battles with the development projects that affect the national parks or reserves. Therefore, it is difficult to be optimistic about ERIP, particularly if the battle has to be won based on environmental grounds alone.”
Fortunately, ERIP cannot be justified even on economic grounds. The existing small irrigation schemes have been found to be much more cost-effective. Furthermore, they run according to traditional methods of sharing water and repair work. These smaller schemes also provide a platform for social cohesion in a diverse and stratified society made up of local ethnic people and hill migrants. An estimated seven cubic meters/sec of Rapti water is being diverted into channels for irrigation to more than 8,000 hectares of land. In a way, ERIP would only be duplicating work in an area which is already benefiting from irrigation. The farmers are bound to resent a project that will bring unnecessary additional burden through future water tax.
If the East Rapti Irrigation Project is given the green signal in its currently proposed form, the Royal Chitwan National Park ecology will see devastating changes, immediately and in the long-run. Nepal will loose its face internationally for backtracking on its support of conservation. International support of wildlife projects might also see a decline as a result. Why risk all this when there are already small but active irrigation schemes at work? Approval of ERIP could, furthermore, signal a go-ahead for other similar projects, such as the Babai Irrigation Project, next to the Royal Bardia National Park in the western Tarai.
It is time that the Nepali government stood up for the environment and bridged the gap between its commitment to environmental policies as stipulated in the National Conservation Strategy, and actual practice.
U.R. Sharma is working for a PhD in wildlife management. He was warden of the Royal Chitwan National Park.