A set of maps from the United States Geological Survey website has sparked debate about the development of affordable housing on the Spenger’s Fresh Fish Grotto’s parking lot, because of information gleaned about the site’s environmental history.

The maps — dating back to 1857 —  reveal that the project site, located on 1900 Fourth St., is a former marshland area not conducive to habitation because it was located predominantly underwater, according to the site’s Draft Environmental Impact Report (EIR). The Ohlone Indians, however, consider the site to be a part of the West Berkeley Shellmound, a city-designated historic landmark, and therefore sacred.

According to the EIR, data for the maps came from field surveys completed by the US Coast Survey in 1856 and depict two mounds to the east and west of the project site on the north bank of Strawberry Creek. The northernmost portion of the site was part of a land mass outside the marsh area.

The maps were referenced in the Draft EIR when it was first published. The EIR, a part of the California Environmental Quality Act, informs governmental agencies and the public about a project’s environmental impact.

Lauren Seaver, vice president of Blake Griggs Properties, a partner in West Berkeley Investors — the company developing 1900 Fourth St. — said these maps were found as part of a “thorough” geological and archaeological research conducted in 2014. According to Seaver, marsh deposits found on the site reveal that it was “uninhabitable” because it was mostly underwater.

“While important in the context of being in an area that is culturally important, the 1900 Fourth Street site has proven to be void of being culturally rich with artifacts and of culturally important discoveries that will have an adverse impact to the historic resource,” Seaver said in an email.

Corrina Gould, co-founder of Indian People Organizing for Change and a descendant of the Ohlone Indians, said the more recent city of Berkeley map, which includes the Spenger’s parking lot within the Shellmound perimeter, takes precedence over the older 1857 map. Gould added the maps do not change the sacredness of the site, citing that she and the Ohlone “came directly from this place.”

“For the developers, it might just be a piece of land,” Gould said. “But for us, it is a place where we pray and honor.”

Seaver said she is sympathetic to Indian People Organizing For Change but feels efforts to preserve the Ohlone cultural heritage are misdirected.

“We believe Corrina’s efforts would be better suited to get the Landmark Commission to broaden the designation of the landmarked area around West Berkeley … which may have potential adverse impacts to the Chochenyo Ohlone cultural heritage if later redeveloped,” Seaver said in an email.

In an email, city spokesperson Matthai Chakko said the 1856 Coast Guard Map was reviewed as part of the preparation of the Draft Environmental Impact Report. According to Chakko, both the Landmark Preservation Commission (LPC) and the Zoning Adjustments Board (ZAB) have held public hearings on the Draft EIR in 2016.

Going forward, city staff will work on creating a final EIR, which will include a response to comments submitted and the Draft EIR. ZAB will hold public hearings in the future to consider certification of the final EIR. After certification, LPC will hold public hearings to consider approval of the Structural Alteration Permit.