De Haro, with his land rights already challenged and fearing that the United States government would now strip him of Potrero Nuevo, agreed to Townsend's suggestion. Together with famed surveyor Jasper O'Farrell, recent emigrant Cornelius De Boom, and Captain John Sutter hashed out the grid and street names. Even before
De Haro, who was already facing challenges over his land ownership and feared losing Potrero Nuevo to the US government, made an agreement with Townsend. Alongside surveyor Jasper O'Farrell, immigrant Cornelius De Boom, and Captain John Sutter, they planned out the layout of the streets and grid before its introduction.