Residential demolition and its impact on vacant lot hydrology: Implications for the management of stormwater and sewer system overflows

Increased residential demolitions have made vacant lots a ubiquitous feature of the contemporary urban landscape. Vacant lots may provide ecosystem services such as stormwater runoff capture, but the extent of these functions will be regulated by soil hydrology. We evaluated soil physical and hydrologic characteristics at each of low- (backyard, fenceline) and high-disturbance (within the demolition footprint) positions in 52 vacant lots in Cleveland, OH, which were the result of different eras of demolition process and quality (i.e., pre-1996, post-1996). Penetrometer refusal averaged 56% (range: 15-100%) and was attributed to high concentration of remnant buried debris in anthropogenic backfill soils. Both disturbance level and demolition type significantly regulated infiltration rate to an average of 1.8cmh^-1 (range: 0.03-10.6cmh^-1). Sub-surface saturated hydraulic conductivity (K_sat) averaged higher at 4.0cmh^-1 (range: 0-68.2cmh^-1), was influenced by a significant interaction between both disturbance and demolition factors, and controlled by subsurface soil texture and presence/absence of unconsolidated buried debris. Our observations were synthesized in rainfall-runoff models that simulated average, high- and low-hydrologic functioning, turf-dominated, and a prospective green infrastructure simulation, which indicated that although the typical Cleveland vacant lot is a net producer of runoff volume, straightforward change in demolition policy and process, coupled with reutilization as properly designed and managed infiltration-type green infrastructure may result in a vacant lot that has sufficient capacity for detention of the average annual rainfall volume for a major Midwestern US city.