Issues Magazine

Expansion without Extinction

By Kiribandage Jinapala

Managing agricultural development while conserving biodiversity is a challenge for practitioners of development and conservation.

Ecosystem and biodiversity conservation are seriously threatened in countries pursuing irrigation as a strategy for economic development. Sri Lanka, for instance, has been implementing large irrigation projects since the country gained independence, but has not paid adequate attention to the protection of its natural resources. As a result, degradation of natural ecosystems is now widespread, with some 560 animal and 690 plant species under threat of extinction.

At the same time, irrigation development is essential for agriculture in the dry zone areas of the country, especially where there is high variability in rainfall. This is the challenge for development and conservation practitioners: to seek innovative strategies to conserve biodiversity while implementing irrigation development programs.

The International Water Management Institute (IWMI), together with the World Conservation Union (IUCN, Sri Lanka) and the Mahaweli Authority of Sri Lanka (MASL) in collaboration with Nippon Koei Japan, implemented a project under the name “Expansion without Extinction”. This project, which ended in December 2005, looked at how biodiversity can be preserved in irrigation systems. It was funded by the Royal Netherlands Embassy of Sri Lanka, and provided an opportunity to get involved in research that would create valuable lessons and generate new knowledge on this topic for the first time.

The project focused on the left bank of the Walawe Irrigation Scheme in southern Sri Lanka. The project area covers two different types of irrigation development: the rehabilitation of the upper portion of the left bank and new construction to create irrigation infrastructure in the lower part of the left bank. This also provided an opportunity to compare irrigation development-induced impacts on biodiversity and the livelihoods of communities.

The overall project goal was to ensure that agro-ecosystems were managed within a sustainable development framework that would contribute to improved livelihoods and biodiversity conservation. The main project objectives were:

  • monitoring trends in biodiversity and socio-economic conditions during the construction and irrigation phase of the project;
  • using monitoring outcomes to identify and strengthen existing biodiversity conservation and livelihood-support activities in the project area through awareness creation and social mobilisation;
  • developing, promoting and implementing a range of eco-agriculture strategies and practices with the active participation of the Mahaweli Development Authority and other relevant government agencies, non-government organisations and local communities. The emphasis was also on institutional and technical capacity building and knowledge sharing;
  • establishing and strengthening of institutions and other mechanisms for participatory conservation-based management in irrigation projects; and
  • structured monitoring and documentation of the processes of implementation and capacity building.

While the upper left bank of the Walawe was developed for irrigation, the southern part of the left bank remained undeveloped. Phase II of the Walawe Left Bank Irrigation Upgrading and Extension Project (WLBIUEP) was initiated for this purpose. It was the last large-scale irrigation development project, and a significant aspect of this project was that it set environmental conservation as one of its main project objectives.

Some of the eco-agricultural strategies put in place by the project were the identification and designation of biodiversity “refuges” in the project area during the pre-development assessment, prior to clearing and development activities. Small tank systems that support dry zone aquatic biodiversity were incorporated into the main system through carefully planned rehabilitation. A biodiversity park was constructed and used as a community education centre, a repository for dry zone biodiversity (genetic material) and a potential eco-tourism location.

Other conservation-relevant measures to mitigate the adverse impact of irrigation development on the environment included the protection of tank reservations and large trees of high resource value, as well as the establishment of a high proportion of indigenous trees in road reservations and fuel wood plantations. The project promoted the development of home gardens with live fencing (shrubs and vines) and other measures to enrich vegetation. A comprehensive action plan was developed with the participation of MASL agency officials, local farmers and other community members for biodiversity conservation and enrichment of natural resources in different locations.

The project created a conducive environment for stakeholders to plan and implement biodiversity and eco-friendly irrigated agriculture development strategies in the project area. Lessons learned from the research project are generic and replicable in Sri Lanka or elsewhere for helping to develop biodiversity- friendly irrigation.