El Caracol, Ecatepec

Approximately 3,200 m in diameter, the levee was part of the original plan to create a solar evaporation pond to extract sodium carbonate (soda ash) and calcium chloride (rock salt) from the mineral-rich underground waters of the former Lake Texcoco.

In 1967, it was discovered that the blue-green algae natural to Lake Texcoco's alkaline waters (which had previously been filtered and discarded) could instead be deliberately cultivated in the El Caracol basin, collected with screens and processed into Spirulina, a dry nutritional supplement powder, for commercial sale.

The Spirulina Mexicana brand remained the world's largest through the 1980s and was one of SOSA Texcoco's most profitable assets; unfortunately, the famous snail shape and repurposed nature of the evaporation basin actually hindered efficient aquaculture operations and forced much of the harvesting work to be done by hand.

However, the primary issue remained that El Caracol was never successfully automated and relied almost entirely on manual labor to harvest either salt or algae; the company's primary efforts were thus to renegotiate the unsustainably generous collective bargaining contracts for manual laborers (exclusively reserved for Institutional Revolutionary Party members in good standing) that were mandated upon SOSA Texcoco by the Madrid administration during the last years of the PRI's 70-year monopoly on Mexican politics as a one-party state ("la dictadura perfecta").

After the Mexican Supreme Court (which was still entirely composed of PRI loyalists) ruled in 1991 that the old contracts must be honored if any profit-seeking business was to resume operations on the site, the new company promptly admitted defeat and folded.