In late August 1857, workers began building fences, clearing vegetation, draining the land, and leveling uneven terrain.[105][70] By the following month, chief engineer Viele reported that the project employed nearly 700 workers.[70] Olmsted employed workers using day labor, hiring men directly without any contracts and paying them by the day.[95] Many of the laborers were Irish immigrants or first-or-second generation Irish Americans, and some Germans and Italians;[106] there were no black or female laborers.[107][108] The workers were often underpaid,[108][109] and workers would often take jobs at other construction projects to supplement their income.[110] A pattern of seasonal hiring was established, wherein more workers would be hired and paid at higher rates during the summers.[108]