Introduction and training resources for the Water Evaluation and Planning (WEAP) tool

Submitted by Sari Ohsada | published 8th Dec 2020 | last updated 24th Feb 2023

Climate Adaptation Training Annotation

  • Level: Introductory
  • Time commitment: 1 hour 
  • Learning product: Tool/method summary
  • Sector: Water 
  • Training language: English 
  • Certificate available: No 
Marisa Escobar discusses the WEAP model


WEAP ("Water Evaluation And Planning" system) is a leading integrated water resources planning tool used by hundreds of organizations worldwide. It provides a comprehensive, flexible and user-friendly framework for policy analysis.

Over the last decade, an integrated approach to water development has emerged that places water supply projects in the context of demand-side issues, water quality and ecosystem preservation and protection in various locations including California in the USA and countries including Lesotho, Kenya and Tanzania in Africa. WEAP incorporates these values into a practical tool for water resources planning.

WEAP is distinguished by its integrated approach to simulating water systems and by its policy orientation, integral to SEI's conceptual five water solutions for an uncertain climate future. WEAP places the demand side of the equation – water use patterns, equipment efficiencies, reuse, costs and allocation – on an equal footing with the supply side – streamflow, groundwater, reservoirs and water transfers. WEAP thus provides a laboratory for examining alternative water development and management strategies.

Institutional background and trainers

Marisa Escobar is the Water Program Director at SEI US. Her work focuses on creating linkages between physical processes and socio-ecological systems. She uses her expertise on water, including water quality, the physics of water, and the movement of water through watersheds, to produce information on the implications of decisions about water on the overall ecosystem.

Jack Seiber, David Purkey, Hector Angarita, Angelica Moncada, Orn-uma Polpanich, Kennedy Muthee, Mario Cárdenas, Dhyey Bhatpuria, Tania Santos, Claudia Coleoni, Emily Ghosh, Nilo Lima, George Ogol, Karthikeyan Matheswaran, Simon Okoth, and many others have also contributed to the development and application of WEAP since its inception, and is now translated in over 25 languages.

Who will find this useful?

The introduction to the WEAP software is designed for participants who:

  • Are entry-level or senior researchers interested in integrated water resources planning that attempts to assist rather than substitute skilled planning
  • Are water professionals seeking for a useful addition to their toolbox of models, databases, spreadsheets and other software

Training materials

Further introductory training videos are available below:

User-defined Variables narrated by Stephanie Galaitsi, SEI US (7:48)


Export WEAP Results to Google Earth narrated by Jack Sieber, SEI US (6:51)


Linking WEAP and LEAP (Long-range Energy Alternatives Planning System) - Energy planning models narrated by Jack Sieber, SEI US (8:35)

If you wish to participate in additional introductory training courses offered throughout the year or participate in the more advanced Q&A see online community forum.

For more videos, click here.

 WEAP Tutorials (English) (Installation, First steps, Basic tools, Scenarios, Hydrology)
 Tutoriales WEAP (Español)
Please also make use of the WEAP YouTube Channel where all training videos can be found.

Learning outcomes

WEAP tool provides:

  • Decision-support through data and/or process collaboration that supports decision-makers in both planning and policy.
  • Awareness raising and learning that helps raise awareness/supports dialogue on specific issues.
  • Research/Analytical perspectives that is helpful towards conducting research, especially for analysing large datasets.
  • Knowledge sharing/network building that enables knowledge sharing and/or networking between people.
  • Guidance to facilitate and improve processes around local, urban, national and regional water resource challenges.

Further resources