Watershed and Stanford Launch Cornerstone to Maintain Key Scope 3 Emissions Models

Climate solutions company Watershed and Stanford University's Stanford Sustainable Solutions Lab have launched Cornerstone, a new initiative to maintain and expand the USEEIO and CEDA emissions models after the U.S. EPA stopped updating the database. The two models together underpin approximately 65% of corporate Scope 3 carbon measurements globally.

The Cornerstone initiative will act as an open-access hub for the U.S. Environmentally-Extended Input-Output model, the EPA's primary carbon accounting model, and Watershed's Comprehensive Environmental Data Archive, a global carbon accounting model. USEEIO's former EPA lead and architect, Dr. Wesley Ingwersen — who was let go from the agency after signing a letter urging the EPA administrator to reconsider new policy direction — will serve as Technical Director. CEDA was originally developed by environmental database provider VitalMetrics, which Watershed acquired in 2023.

The initiative addresses a significant risk to global corporate climate measurement: the U.S. EPA has reportedly announced it will no longer update USEEIO, threatening the continuity of Scope 3 accounting that underpins sustainability disclosures for thousands of companies worldwide. CDP data cited by Watershed indicates the two models are used for around 65% of Scope 3 measurements globally. Companies in India reporting under BRSR Core and those aligning with ISSB standards rely heavily on internationally recognised input-output models for value chain emissions estimates.

Under Cornerstone, USEEIO and CEDA will merge into a single global open multi-regional input-output model in the coming months, expanding measurement beyond greenhouse gases to include regional air and water quality, water use, and waste generation. The Stanford Sustainability Lab will lead research applying the model to energy and food systems sustainability challenges. Watershed plans to onboard additional open-source contributors over time to ensure the model remains current and independent of political influence.

Key figure — 65% of global Scope 3 corporate carbon measurements rely on USEEIO and CEDA