Comparison of Maintenance Cost, Labor Demands, and System Performance for LID and Conventional Stormwater Management

Abstract

The perception of the maintenance demands of low impact development (LID) systems represents a significant barrier to the acceptance of LID technologies. Despite the increasing use of LID over the past two decades, stormwater managers still have minimal documentation in regard to the frequency, intensity, and costs associated with LID operations and maintenance. Due to increasing requirements for more effective treatment of runoff and the proliferation of total maximum daily load (TMDL) requirements, there is a greater need for more documented maintenance information for planning and implementation of stormwater control measures (SCMs). This study examined seven different types of SCMs for the first 2-4 years of operations and studied maintenance demands in the context of personnel hours, costs, and system pollutant removal. The systems were located at a field facility designed to distribute stormwater in parallel in order to normalize watershed characteristics including pollutant loading, sizing, and rainfall. System maintenance demand was tracked for each system and included materials, labor, activities, maintenance type, and complexity.

Assessing cost-effectiveness of specific LID practice designs in response to large storm events

“…In Hong Kong, the annualized O&M costs are expressed as a percentage of the capital costs -4% for porous pavement and 8% for bioretention (Houle et al, 2013). The O&M costs of green roof are extracted from Townshend and Duggie (2007 Table 3 presents some example O&M activities.…”

Review and Research Needs of Bioretention Used for the Treatment of Urban Stormwater

“…Since maintenance requirements for bioretention practices are still being established [30], costs will then very substantially based upon what activities are conducted. In a recent study, Houle et al [142] provided insight into maintenance activities by tracking costs and labor demands for bioretention practices over a period of 2-4 years. The authors found that despite conventional wisdom, LID practices such as bioretention, which typically require proactive rather than reactive maintenance, experience lower marginal costs than conventional practices.…”

Comparative analysis of modeled nitrogen removal by shellfish farms

“…Nonpoint sources of nitrogen, due to their diffuse nature, are more challenging to address on an ecosystem scale. Typically, runoff from agricultural fields and stormwater are two of the major focus areas of management plans for reducing nonpoint sources of nitrogen (Collins et al, 2010;Houle et al, 2013;Passeport et al, 2013).…”