Stormwater Quality Master Plan

E Sciences developed and is currently implementing a Stormwater Quality Master Plan for the City of Melbourne. The master plan optimizes the approach to meet recently expanded water quality regulations. The City of Melbourne currently participates in two ongoing Basin Management Action Plans or BMAPs. Typically, these BMAPs require the implementation of Best Management Practices (BMPs) and projects to reduce nutrients and other stormwater pollutants prior to discharge to impaired water bodies. E Sciences’ innovative approach to address these needs included a citywide water quality model to identify “hot-spots” of highest nutrient loads and development of a prioritized implementation strategy of specific projects to reduce nutrient loading.

An updated stormwater quality model was developed for all areas within the 35-square mile city. The Pollutant Load Screening Model (PLSM) was selected from amongst several potential models primarily due to the spacial model framework within GIS. Additionally, the PLSM was used by FDEP in the creation of the nutrient load allocations in the Indian River Lagoon BMAPs and the model results can be easily compared to the FDEP model. With a thorough understanding of the source of the water quality issues, projects were developed to target specific areas to optimize improvements to the existing stormwater system.

In an effort to better understand the drainage characteristics within the City, E Sciences developed a stormwater infrastructure inventory using a variety of data sources. An ArcGIS geodatabase was developed to store the combined data in a single repository. Data sources included the City’s existing infrastructure database, a hard-copy stormwater inventory developed in 2003, FDOT as-built plans, St. Johns River Water Management District (SJRWMD) Environmental Resource Permit database, and the City’s archive of AutoCAD files, permit documents and construction plans dating back to the 1950s. The stormwater infrastructure inventory provided a strong foundation for the location and design of new water quality BMPs.

With the most current stormwater infrastructure and high pollutant load areas identified, E Sciences developed conceptual designs for more than 50 projects in order to estimate project construction and implementation costs compared to the anticipated project-specific pollutant removal benefit. Project development efforts focused on the areas within the City with the highest concentration of pollutant loads and locations that have high stormwater runoff. Project areas were identified in GIS by evaluating watershed characteristics using LiDAR for basin delineation and flow routing. Project BMPs were designed based on existing stormwater infrastructure and using GIS land use/land cover layer, soil type layer, and ERP design files from nearby projects. Our staff analyzed the attributes of potential projects using a comparative matrix to establish a prioritized list of projects. The prioritized list provides the City with a strategic and cost effective plan for implementation.

Throughout the process of locating and designing projects, E Sciences consulted with staff to ensure that the projects were practical and consistent with the development goals of the City. This included meetings with the City’s Engineering Department, GIS Department, Parks Department, Golf and Leisure Services Department, Public Works and Utilities Department, Environmental Community Outreach Division and the Planning and Economic Development Department. Communication and coordination with each of these groups was essential to ensuring that the development of water quality improvement projects leveraged the full potential resources of the community.

Funding for water quality improvements is available from national, state and regional sources. The stormwater master plan identifies these sources and the criteria for which funding can be requested. When funding from these sources becomes available, having a list of projects to choose form can make the process and application much more efficient. E Sciences has been able to provide successful support for the application and acquisition of grant funding. Currently, E Sciences is assisting the City in obtaining over $100,000 for water quality project development identified in the stormwater master plan.

E Sciences continues to work with the City of Melbourne on design, permitting, real estate acquisition, grant award/management, construction, and water quality monitoring of recommended projects.