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Public Projects

Charles P. Johnson & Associates has been working in the Maryland, Virginia, Washington D.C. metro area since 1971. We have accumulated a diverse portfolio of projects from our four offices that show our array of skills and the breadth of our reach. We have planned, engineered, and surveyed everything from residential and commercial developments to roads, streams, and stormwater management systems. Many of our projects are from repeat clients, which demonstrates our commitment to excellence, and their satisfaction.

Public Projects: Projects
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Germantown Town Center Urban Park

Charles P. Johnson and Associates, Inc. (CPJ) was contracted by the Maryland-National Capital Park and Planning Commission Department of Environmental Protection (M-NCPPC) to provide civil engineering design services for the design of an urban park at the Germantown Town Center.  As part of these services, CPJ completed a stormwater management plan for the park that included retrofitting existing stormwater management and traditional drainage infrastructure, constructing low impact development (LID) practices to provide stormwater management, and converting the remaining open space to a park for public use.  After conducting a hydrologic and hydraulic study of the site, CPJ completed retrofit designs to bring the existing facilities into compliance with current stormwater management and safety standards. Once the designs were completed, approved and fully permitted by local and state regulators, CPJ assisted the M-NCPPC by completing a full set of bid documents for each facility and managing construction on behalf of the M-NCPPC.


Clean Water Partnership
Prince George's County, MD

  Since 2016, CPJ has been under contract as one of two main design consultants for the Clean Water Partnership.  CPJ has been tasked with finding, qualifying, designing and permitting stormwater management project for the Partnership. 

  The Clean Water Partnership was formed to meet the stormwater management treatment goals of the County’s Municipal Separate Storm Sewer System (MS4) permit issued by the Maryland Department of the Environment.  The goal of the CWP is to retrofit 2,000 acres of County-owned property with the installation or construction of BMP’s to store or treat storm water runoff in order to mitigate flooding, reduce pollution loads and achieve impervious area credits, which will be used by the County to certify stormwater compliance under the MS4 Permit. 

  Once a facility is identified, CPJ analyzes each facility to determine site constraints and develop a conceptual design that maximizes stormwater treatment.  CPJ presents the preliminary design to the Clean Water Partnership for acceptance and stakeholder coordination prior to obtaining permits and assists with community outreach by presenting the projects at community meetings.

  CPJ prepares the plans and documents necessary to obtain permits from the County and State agencies including stormwater management, sediment control, natural resources, dam breach studies, and utility coordination, working closely with the Peer Reviewers, regulatory agencies until approvals are received, and permits issued.

  To date CPJ has successfully permitted six stormwater retrofit projects totaling 75 acres of permitting credit.

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Upper Watts Branch Forest Preserve Stream Restoration and Outfall Stabilization

The City of Rockville contracted CPJ to work closely with the Upper Watts Branch Citizen Task Force to evaluate the entire Upper Watts Branch Forest Preserve Stream Valley, including two miles of stream, and make recommendations for the restoration of degraded channels, enhancements to wetlands, improvements to storm drain outfalls and protection of sanitary sewer mains. Over the course of the next several years CPJ and Hazen staff met with the task force on a monthly basis to both educate the members on the processes and data gathering process as well as report on the assessment and recommendations for restoration.  Ultimately, four separate outfalls with severely degraded channels and 1,210 linear feet of perennial stream channel were restored within the Park.

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Hollywood Tributary Stream Restoration

CPJ was awarded a task order contract to assess stream stability along an approximately one mile of Hollywood Branch, a second order tributary to Paint Branch.   The goals of the project were to design restoration approaches to stabilize erosive areas, improve floodplain access, enhance riparian conditions, enhance stream conditions and improve overall aquatic resources.  CPJ prepared full construction documents and acquired all required permit approvals and the design was bid through DEP’s prequalified stormwater management and stream restoration contractor program.

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