HOME / INDUSTRY OUTREACH / TECHNICAL PAPERS Retrofit of Storm Water Treatment Controls in a Highway Environment A storm water treatment control pilot program was developed to assess the costs and benefits of retrofitting conventional structural Best Management Practices (BMPs) into highway infrastructure. The program was unique in that thirty-nine installations were sited, designed, constructed, operated, and maintained using consistent criteria, monitoring and testing protocols over a five-year period. Consequently, this study is thought to be the most comprehensive investigation of conventional structural BMP performance completed to date. Design and Permitting Challenges of Highway Constructed Treatment Wetlands Over the past several years, the California Department of Transportation (Department) has initiated various pilot projects to assess the performance and applicability of multiple storm water Best Management Practices. In 2001, the Department embarked on a multi-year pilot project to design, construct, and investigate the water quality performance of a CTW and wet detention pond along State Route 73 (SR-73) in southern California. This paper primarily focuses on the design and permitting challenges from the 2001 project in southern California. For the SR-73 project, water quantity and quality data from flow-composite samples of storm water runoff will be collected over a three-year period. Other factors such as maintenance thresholds, the ability to produce vectors, and cost to construct and maintain these wetland-type BMPs will also be investigated. Stormwater Pollutant Removal in Roadside Vegetated Buffer Strips The Roadside Vegetated Treatment Sites Study was a two-year water quality monitoring project undertaken to evaluate the removal of storm water contaminants by existing vegetated slopes adjacent to freeways. The objectives of this study were to determine if standard roadway design requirements result in biofilter strips with treatment equivalent to those specifically engineered for water quality performance, and to generate design criteria. Design and Construction Experiences with Three Variations of Austin Style Sand Filters in the Transportation Environment The California Department of Transportation (Caltrans) has initiated a three-year pilot project to investigate the water quality performance of two Austin Sand Filters designed incorporating alternative configurations and/or alternative construction materials to reduce capital costs while maintaining water quality performance. This paper presents: (a) a discussion of the design methodologies for the full and partial sedimentation Austin Sand Filters; (b) comparison of construction costs between three variations of Austin Sand Filters (EPSF, EFSF, and CFSF); (c) the preliminary water quality data for the Northern California pilot project; and (d) a preliminary comparison of water quality performance between the Northern California pilot project and the Southern California pilot project. Optimal Pump Operation of Water Distribution Systems Using Genetic Algorithms The water utility industry has started investigating the integration of on-line telemetry and optimal computer control systems in an effort to reduce operating costs and provide more reliable operations. This paper presents a new management model, H2ONET Scheduler, for optimal control and operation of water distribution systems. The proposed model makes use of the latest advances in genetic algorithm optimization to automatically determine the least-cost pump scheduling/operation policy for each pump station in the water distribution system while satisfying target hydraulic performance requirements. Constructing a Pipeline to Partnership The Otay Water District, located in San Diego, California, identified the need to replace 3,000 feet of deteriorating pipeline. As the Inter-Connection Project was developed, the pipeline grew from 3,000 feet to over 12 miles. Through the utilization of a pipeline, the District optimized their storage capacity of potable water, and increased service reliability to their customers. The project has provided several opportunities for partnerships through the creativity of the District. This project, which many viewed as impossible, stands as an example of what can be accomplished when partnerships are created to overcome the largest obstacles for projects today, no longer the engineering aspects, but the institutional factors. A Stable Channel Design Approach for the Rio Salado, Salt River, Arizona Planned environmental restoration of the Rio Salado (also known as the Salt River) involves the design and construction of a stable soft-bottom low flow channel through a 8-kilometer (5-mile) project reach in Phoenix, Arizona. This paper presents a design approach for a stable low flow channel on the Rio Salado. A Wet Pond as a Storm Water Runoff BMP - Case Study The California Department of Transportation (Caltrans) has initiated a five-year study in San Diego to examine the benefits, technical feasibility, costs, and operation and maintenance requirements of using a wet pond to treat storm water runoff from an existing freeway. The purpose of this program is to study the opportunities and constraints, relative to siting, design, construction, operation and maintenance, associated with retrofitting highways with this type of stormwater Best Management Practice (BMP) and to evaluate the efficiency of the device for removing pollutants of concern. Five aspects of this wet pond case study are discussed here -- siting, design, construction, operations and maintenance, and efficiency evaluation. Constraints, problems, and solutions of the siting, design, and construction are presented along with the and the study design for the operation, maintenance, and efficiency evaluations. Development of Appropriate Stormwater Infiltration BMPs: Part II - Design of Infiltration BMPs Infiltration BMPs treat a portion of Stormwater runoff or "capture" volume by infiltrating a portion of the runoff into the soil. Infiltration practices include basins, trenches and porous pavement. This paper presents design guidance for infiltration basins and trenches. Three primary topic areas will be discussed; 1) Site selection, 2) design guidance and 3) maintenance and operation. Sizing Water Distribution Mains for Fire Protection Fire demands can have a significant impact on the size of a water distribution system. These demands create additional localized stress on the water system and may induce undesirable areas of low pressures. Sound engineering design practice dictates that the distribution system be capable of delivering all fire flows at the required minimum pressure. This paper describes an explicit and rigorous model that is able to directly perform accurate fire flow calculations under a wide range of network loading and operating conditions. Enhancement of distribution system design, planning, and management is a principal benefit of the methodology. Receiving Water Quality Monitoring for Assessment of Storm Water Runoff Impacts, A Case Study Traditional storm water monitoring programs fail to provide a link between the sampled parameters and pollution in the receiving water because it is necessary to try to extrapolate from the concentrations of a constituent in the runoff to a water quality impairment in the receiving water. A receiving water quality monitoring program termed 'evaluation monitoring' was developed to directly assess whether there is a real water quality impairment in the receiving water due to a constituent rather than assuming a problem is present through proxy chemical sampling. The implementation of evaluation monitoring discussed in this case study focuses on toxicity in San Diego Creek and Upper Newport Bay in Southern California as an identified priority for the receiving water. The program ultimately includes identifying the cause of toxicity, determining the cause (constituent(s)), and developing a cost-effective control program. Construction of a New Tollway Below the Groundwater Table with Nitrate Remediation A new tollway presently under construction in Orange County, California will extend over 38 km linking three existing freeways. About 2 km of this new roadway construction will occur below the existing groundwater table. The roadway intersects a shallow unconfined aquifer comprised of a highly heterogeneous soil structure, making discharge predictions a challenge. A history of farming in the area has left the shallow aquifer with high TDS and nitrate concentrations, effectively prohibiting the discharge of the groundwater to surface waters and limiting the water's beneficial use opportunities. A significant number of alternatives were investigated for use and/or disposal of the effluent over the long term.