An Issue of Sewerage: The role of Ellen Swallow Richards in Broad Irrigation at Vassar College and the present day impacts of excavation on Haven Loam soil

From 1896 to 1909, a system of sewage disposal existed on the Vassar farm, purifying sewage through sandy soils and irrigating the adjacent crop fields. This system was ecologically innovative in its time and Ellen Swallow Richards, a Vassar alumna, professional chemist, and pioneer in ecology, played an instrumental role in the placement of this sewage disposal system. Today, this area is part of a revegetated deciduous forest on the Vassar Farm and Ecological Preserve, but disturbance from more than one hundred years before is still evident in the composition and texture of the underlying sandy, permeable soil called the Haven Loam (HeA). This study explores Ellen Swallow Richards’ role in the commissioning of the sewage system and surveys the Haven Loam soil at the site of the system on the Vassar Farm. Archived minutes of the Vassar College Board of Trustee Meetings, personal letters, and academic publications suggest that Ellen Swallow Richards’ was very influential in the decision to build a sewage farm and knew the system would be successful due to the sandy quality of the soil. Physical properties of Haven Loam soil were examined for field texture, structure, consistency, and permeability. Organic matter content (% LOI) and hydrometer fine fraction tests were performed. Additionally, X-ray diffraction was performed for sampled soil and experimental patterns were modeled to generate clay mineral compositions for different sites. Disturbance from excavation of soil to build the sewage system has resulted in alterations to soil stratigraphy and reduced Cation Exchange Capacity of subsoil beneath the infiltration beds.