Welcome to WEAP's Website WEAP
WEAP is an initiative of the Stockholm Environment Institute.

About WEAP

What's New?
Sample Screens
History and Credits

Using WEAP
User Guide
Videos (YouTube)

User Forum
Members List
Edit Profile

Additional Support
University Courses

About Us
SEI-US Water Resources Program
Please Contact Us

Interested in Energy?
Read about LEAP: SEI's software for energy planning.

Link WEAP and LEAP for combined Water-Energy planning.
Watch a video demo!

History and Credits


WEAP was created in 1988, with the aim to be a flexible, integrated, and transparent planning tool for evaluating the sustainability of current water demand and supply patterns and exploring alternative long-range scenarios.

The first major application of WEAP was in the Aral Sea region in 1989 with the sponsorship of the newly formed Stockholm Environment Institute (SEI). SEI continued to support the development of WEAP through its US Center (SEI-US), which was established in 1989 and hosted by the Tellus Institute until 2006. Over the years WEAP has been applied in many countries and river basins. The software has been transferred to water planners throughout the world.


The development and distribution of the WEAP software is managed by Jack Sieber of the Stockholm Environment Institute (SEI).

WEAP was conceived by Paul Raskin, President of Tellus Institute, and developed under his supervision until 2001. Many have contributed to the development and application of WEAP since its inception. We would like to acknowledge, in particular: Paul Raskin, Charlie Heaps, Eugene Stakhiv, Ken Strzepek, Zhongping Zhu, Bill Johnson, Evan Hansen, Dmitry Stavisky, Mimi Jenkins, Jack Sieber, Paul Kirshen, Tom Votta, David Purkey, Jimmy Henson, Alyssa Holt McClusky, Eric Kemp-Benedict, Annette Huber-Lee, David Yates, Peter Droogers, Pete Loucks, Jeff Rosenblum, Winston Yu, Chris Swartz, Sylvain Hermon, Kate Emans, Dong-Ryul Lee, Si-Jung Choi, David Michaud, Chuck Young, Martha Fernandes, Brian Joyce, Chayanis Krittasudthacheewa, Andre Savitsky, Daene McKinney, Marisa Escobar, Amanda Fencl, Vishal Mehta, Johannes Wolfer, Markus Huber, Abdullah Droubi, Mahmoud Al Sibai, Issam Nouiri, Ali Sahli, Mohamed Jabloun, Alex Bedig, Jean-Christophe Pouget, Francisco Flores, Scott Ligare, Laura Forni, Anne Hereford, Stephanie Galaitsi, Nick Depsky, Bart Wickel, Matthew Holland, Manon von Kaenel, Susan Bresney, Doug Chalmers, Jeanne Fernandez, Nilo Lima, Angelica Moncada, Claudia Coleoni, Tania Santos, Angela Lavado, Doreen Brown Salazar, Marina Mautner, Chris Calderon, Sarah Wingfield, Mohamed Mowafy, Khanh Nguyen, Romina Díaz Gómez and Wendi Jiang.


Many organizations have generously contributed major funding for the development of WEAP. We gratefully acknowledge:

And to the many users of WEAP who have contributed to WEAP development by purchasing WEAP licenses.


Language translations have been generously contributed by:

Back to Home Page