
EWA Effectiveness Studies
The purpose of the Monitoring and Assessment permit requirement in the Eastern WA Permit is to conduct studies to determine the effectiveness of the Stormwater Management Program and communicate the findings to the region.
The effectiveness studies focus on Best Management Practices (BMPs) used by Permittees and include studies focused on operational, or structural BMPS, or education and outreach practices.
2014-2019 Permit Cycle
This study aims to investigate whether the frequency of street sweeping significantly influences sediment accumulation in catch basins (and transport from catch basins) during the dry season in a semiarid location.
The goals for this study will be achieved by conducting field testing two bioretention cells with 18-inch and 12-inch depths of BSM. The field testing will involve using automated equipment to collect data at a site at Gonzaga University in Spokane.
– Bioretention Soil Media Thickness Study QAPP
The goal of this study is to evaluate the effectiveness of the proposed BMP. Effectiveness will be based on the following: 1) The ability of the BMP to infiltrate stormwater during 6-month 24-hour storm events without overflowing into the bypass system within the maintenance cycle 2) The efficacy of the BMP to reduce the concentrations of total suspended solids (TSS), dissolved copper (Cu) and zinc (Zn), and oils, which will be evaluated to determine whether the BMP can achieve the respective Ecology treatment goals
– Sand Filter Sidewalk Vault BMP QAPP
The focus of this study is to evaluate the effectiveness of a non-vegetated filtration swale.
The focus of this study pertains to real-world field application of a storm garden with engineered soil amended with biochar. Garland Avenue was the location selected for the construction of the gardens, and this study measured the percent reduction of nutrients, selected heavy metals, and petroleum hydrocarbons.
The goal of this study is to assess the effectiveness of permeable pavements concerning durability, infiltration rates, and water quality of infiltrated stormwater effluents.
The goal of this study is to assess the effectiveness of the recorded O&M agreement as a regulatory mechanism to educate all owners within a subdivision about the BMP serving their neighborhood and the responsibility of the HOA or other neighborhood organizations to maintain and inspect the BMP by evaluating the level of BMP owner awareness throughout the entire subdivision.
2019-2024 Permit Cycle
The study results indicate that the Drain Rangers program has a very positive effect on educating students about stormwater effects and solutions. This included a 22% increase in expressed actions to address stormwater issues, a 67% increase in scoring for stormwater knowledge and solutions, and a 17% increase in expressed attitude that personal actions can make a positive difference in keeping waterways clean and healthy.
This study aimed to assess the effectiveness of the Dump Smart education and outreach program in eastern Washington, specifically for carpet cleaning contractors.
– Mobile Contractor Illicit Discharge E&O QAPP
This study aimed to evaluate the effectiveness of a non-vegetated filtration swale BMP. Effectiveness was based on whether the BMP was able to provide basic treatment (80% reduction of total suspended solids [TSS]) in accordance with Ecology treatment performance goals as defined in the Technology Assessment Protocol – Ecology (TAPE) Guidance Document (Ecology, 2018).
– Non-Vegetation Filtration Swale QAPP
This study will evaluate the effectiveness of an E&O program for the City of Ellensburg and measure the adoption of targeted behaviors by the target audience. The stormwater pollutants of concern addressed by the E&O Program are cooking-related F.O.G. and wash water. F.O.G. and wash water are commonly created at restaurants and can create an illicit discharge if improperly disposed of. The E&O program will, therefore, focus on restaurants located within the city limits of Ellensburg, Washington, specifically fast-food establishments.
The focus of this study was to evaluate procedures developed by other jurisdictions to meet inspection, maintenance, and enforcement (O&M) permit requirements for structural best management practices (BMPs) on privately owned property.
The goal of the study was to evaluate the effectiveness of a new education program that informs the public about preferred car-washing BMPs to prevent runoff from entering storm drains and discharging to receiving water bodies.
– Car Wash Wastewater E&O QAPP
(Site Construction to begin June 2024; Sampling August 2024-September 2024)
This effectiveness study will evaluate the infiltration ability and treatment efficacy of two non-vegetated bioretention cells. to 1) determine how the infiltration behaviors of non-vegetated cells change with respect to season and in the presence of deicer, and 2) determine if the pollutant removal efficiencies are impacted with respect to variable temperature, pollutant loading rates, and pollutant species across the seasons and in the presence of deicer. The objective of this study is to determine the effectiveness of a non-traditional approach to bioretention design that would be easier to maintain and less costly to install. The study is being performed cooperatively by the City of Spokane, the City of Spokane Valley, and Spokane County.
– NOTE: Ecology review of the QAPP is not complete; therefore, the final QAPP is not yet ready to be posted.