WATER RESOURCES

Water is a critical resource in Florida fundamental to the residents, the natural environment, the agricultural economy and recreational opportunities. Balancing the demands of a growing population with the need to protect the natural ecology of rivers, lakes, wetlands and estuaries requires thoughtful planning and infrastructure investment. CMA is committed to providing innovative solutions that help manage and protect Florida’s most important resource.

Water Works

The natural climate of Florida often provides excess water during the wet season and a deficit of water in the dry season. The successful economic development of Florida relies on infrastructure that can store or divert excess water to provide flood protection as well as manage and store water to provide for potable and irrigation supply when resources are scarce. Because of the large volumes of water and minimal topographic relief, the type of infrastructure needed to manage water at a regional scale in Florida are large civil water works. CMA staff has experience in the design and construction of canals, gated control structures, pump stations that move millions of gallons of runoff, and above ground impoundments that store and treat thousands of acre-feet of water. CMA is invested in continuing our role in the design, construction, and operation of large-scale water works projects that allow Florida to continue to grow and thrive.

Hydrologic & Hydraulic Modeling

CMA has a long history of using hydrologic and hydraulic models as a tool to evaluate flood protection issues locally, regionally, and statewide. These models allow us to work with our clients to understand flooding issues and develop flood protection solutions at any scale. Our staff utilizes a wide array of hydrologic and hydraulic modeling tools from simple one-dimensional node-link simulations to fully integrated two-dimensional surface water models linked to finite difference groundwater models. Our staff includes several PhDs that act as technical leads in the development of models and post-processing tools that translate the results into illustrations and maps that can be shared with stakeholders in a public forum. In many cases, CMA has used these models to develop a list of flood mitigation projects with conceptual plans and cost estimates tailored for use in Capital Improvement Plans. These documents are implementable plans that provide our clients with guidance to program the funding and construction of each identified project.

Sea Level Rise & Resiliency

The Intergovernmental Panel on Climate Change (IPCC) has identified a range of potential sea level rise scenarios for the next 50 years that show the tidal conditions in Florida increasing anywhere from 21 inches to 64 inches. Because Florida relies on gravity discharge for excess runoff, has a high-water table, and virtually no topographic gradient, the potential sea level rise translates to significant uncertainty for the built environment. For every infrastructure project CMA looks at the criticality of the proposed improvements in comparison with the projected sea level rise and the conditions of the project location to determine exposure of the features during their expected useful life. If there is significant exposure, the design must include elevating, hardening, or water-proofing the features. If the sea level rise will not have adverse effects until after the project requires replacement, CMA evaluates the need for future adaptation. If the sea level rise will impact the features but they are not critical infrastructure CMA will develop a design that can accommodate intermittent flooding. As an example, if a new outfall to tide is being designed for a stormwater management system, CMA would determine if the seawall elevation needed to be increased or if a tidal check valve should be installed to prevent backflow and king-tide flooding. If projected sea level rise shows that the gravity discharge can be accommodated now, but it will not suffice in the future, CMA would recommend a configuration that can accommodate an upgrade to a pump station. Areas determined to be non-critical infrastructure green and blue solutions such as bioswales, rain gardens, and living shorelines would be recommended to mitigate the effects of intermittent tidal flooding and provide additional resilience.

Watershed Management & Water Quality

Since 1972 the Clean Water Act has facilitated the implementation of the National Pollutant Discharge Elimination System (NPDES) program in communities throughout the country. This program created a template for managing Municipal Separate Storm Sewer Systems (MS4) in urban areas and non-point pollution sources in rural areas. CMA has extensive experience managing the NPDES program for the various agencies and developing the necessary reports to ensure compliance. The data collected for drainage infrastructure or maintenance programs are formatted in a manner that seamlessly integrates with the NPDES requirements. CMA also works with regional agencies to evaluate monitoring and compliance plans for water quality programs as well as establishing the performance and benefits of implementing Best Management Practices (BMPs) for protecting Florida’s waterways.

Neighborhood & Municipal Drainage

Since our founding CMA has established an expertise designing and constructing retrofits to aging infrastructure in residential neighborhoods and municipal areas. Using survey data to build topographic surfaces and simple hydraulic models, CMA can diagnose the cause of anything from small ponding concerns to structural flooding, then develop the grading plans and specify the drainage infrastructure needed to address the concern. Our staff has designed and constructed a wide range of stormwater facilities to solve local flooding issues including detention ponds, bioswales, exfiltration trenches, and pump stations. Each solution is tailored to the three key project constraints: budget, schedule, and regulatory feasibility. Our experience allows us to foresee issues in each of these constraints and address them during preliminary design to allow our clients the opportunity to choose the project implementation path that best fits the situation.

Sea Level Rise

CMA applies a holistic approach to stormwater infrastructure, considering existing facilities, water quality, resiliency, and Sea Level Rise. Following the Urban Land Institute (ULI) recent recommendation for stormwater improvements in the face of Sea Level Rise, CMA will work with the City to incorporate not only “gray” infrastructure, but also incorporate “blue” and “green” infrastructure. “Gray” refers to engineered components, such as raising roads, drainage inlets, pipes, drainage wells, outfalls, and potentially pump stations. The “blue” and “green” infrastructure refers to natural methods of stormwater treatment and attenuation, such as bioswales, curbed rain gardens, and living shorelines. These components are additional tools in the toolbox to reduce rainfall runoff and add water quality treatment. In addition to building resiliency and sustainability into the stormwater system, items like bioswales reduce the heat island effect common to areas with large amounts of impervious area.

Flood Protection

As sea level rise and increased rainfall intensity has become a more evident driver of flooding, CMA has responded with infrastructure designs that improve resiliency within communities. In the City of Miami Beach, we provided engineering and construction administration on a design-build project for the Sunset Islands that elevated roadways and constructed stormwater pump stations to provide positive discharge and access to critical facilities even as the tailwater elevation rises. We have also provided engineering solutions to conveyance canals, bank stabilization, large culverts and water control structures. Each of these facilities are critical components of the infrastructure that provides flood protection in our communities

Stormwater Management Site-Specific Low Impact Design

Historically, the practice of civil engineering has focused on designing drainage systems that discharge excess runoff in a manner that protects on-site improvements and prevents negative impacts downstream. In recent years, there has been a recognition that a more comprehensive approach to managing stormwater provides additional benefits including improving water quality and promoting aquifer recharge for water supply. At CMA, we leverage the in-house expertise of our Landscape Architecture Department to promote the use of Low Impact Design (LID) techniques that reduce impervious surfaces and promote natural attenuation and infiltration prior to conveyance and discharge. On multiple municipal projects, our design team has identified opportunities to reduce pavement widths on roadway corridors and increase planting spaces. On every project, our design team looks for opportunities to incorporate Best Management Practices (BMPs) and pollution control devices to promote sustainability and resilience.

Stormwater Management: Basin Scale

CMA has prepared basin scale stormwater master plans for multiple municipalities and jurisdictional agencies. This experience has allowed us to understand how regional systems at the basin scale interact with local systems at the neighborhood scale. Our staff utilizes a wide array of hydrologic and hydraulic modeling tools to simulate the regional canals for representation of the tailwater conditions that secondary stormwater facilities rely on. These modeling tools are also utilized to simulate the conveyance capacity and available storage at the neighborhood scale. Over the years we have learned that although the development of a hydrologic and hydraulic model is critical for a good plan, it is not the most important deliverable. The true value of any stormwater master plan is an actionable plan for implementing practical improvements. Our decades of experience designing and constructing neighborhood improvement projects have served us well in developing conceptual plans and cost estimates tailored for use in Capital Improvement Plans that guide future programming for each municipality.

Water Quality

Since 1972 the Clean Water Act has facilitated the implementation of the National Pollutant Discharge Elimination System (NPDES) program in communities throughout the country. CMA has extensive experience managing the NPDES program for the various municipalities and developing the necessary reports to ensure compliance. This experience allows us to understand the value of making sure any data collected for drainage infrastructure or maintenance programs should be formatted in a manner that seamlessly integrates with documentation requirements.