This project began as a typical DC Row House Renovation project. The existing 3-story row building was cleaned down to the floor joists and walls, which served as the starting point to begin this building’s transformation. DeMarr Civil Engineers walked the property with the Project Architects during the project kickoff meeting to fully understand the vision and project goals. The DeMarr Civil Engineering Team worked closely with the owner and Architects to provide all of the Land Surveying and Civil Engineering services needed for this Manifest Project.
DeMarr Engineering began its civil engineering services with surveying the location and elevations of all the exterior features on and around the site with high precision surveying equipment. This included surveying the location and invert elevations of the public storm and sanitary sewer mains in the street (Figure 2).
With a focus on efficient service, detailed civil engineering design, and constructability of our designs, DeMarr employs an in-house survey crew to collect complete and precise survey measurements for our Civil Engineers to use for design (Figure 3). In order to meet our own high quality standards and project deadlines for our clients, DeMarr Engineering prefers to avoid sub-contracting out surveying work in order to have more control of survey data collection process in-house.
After the field survey work was complete, DeMarr Engineering produced an Existing Conditions Plan (Figure 4) showing the location of the row house, property lines, trees, sidewalk, topography, impervious areas, public street frontage, and underground utilities. This survey drawing served as the basis for DeMarr to begin designing the DC Water Plan, E&S Plan, and Site/Grading Plan. DeMarr shared this document in both PDF and DWG format with the owner and Architecture Design team for the Project Architects to use the measurements from our survey.
With any building renovation project in Washington, DC, adding bathrooms and water fixtures to the building will require a DC Water Plan. On small projects in DC, the existing sewer lateral can typically be reused; however, the existing water service line is usually inadequately sized to meet the new water supply demand of the building. Even if the existing water service line is adequately sized, a separate fire service line will be required if sprinklers are required for the building.
On this particular Manifest project, DeMarr prepared the DC Water Plan (Figure 5) to reuse the existing sewer lateral but added a new sewer cleanout pipe to the sewer lateral to add future maintenance capability. Then DeMarr designed a new domestic water pipe and separate fire service pipe connection from the building to the city water main in the street. To ensure proper sizing of the fire and domestic water connections, DeMarr Civil Engineers worked with the interior MEP Engineer to confirm the service connections would meet the water supply demand of the building. DC Water reviewed and approved the plan for permits to begin construction.
After plan approval, DeMarr Engineering advised on the construction work of tapping into the public water. The installation work for larger water connections, typically for fire sprinkler service, requires temporarily turning off the water main for the entire city block and is supervised by DC Water inspectors. Therefore, this work is performed around midnight so that the water main shutdown of a few hours does not inconvenience residents in the affected city block (Figures 6 & 7).
Figures 6 & 7: Water main connection work being performed at midnight.
DeMarr Civil Engineers worked with the Landscape Designer and Architects to incorporate planters, seating areas, a walkway, steps, and a green roof to the Site Plan. DeMarr prepared the Site Plan proposing all of the desired site improvements in relation to the property lines and designed a grading plan to specify elevations for all of the steps leading to the site and building. DeMarr also designed the slope of the walkways and yard for proper water runoff drainage.
In addition to the Site/Grading Plans, DeMarr also prepared the Erosion Control Plans (Figure 8) showing the limits of disturbance, then location, notes and details of all perimeter control silt fence. DeMarr submitted the E&S Plan to the City to be reviewed, approved, and permitted by the Department of Energy and Environment (DOEE).
Any construction project in Washington DC that proposes work past the private property line and into public space owned by the city will require a Traffic Control Plan. The District Department of Transportation (DDOT) reviews these plans to ensure that the proposed construction activities in public space will protect the safety and flow of both pedestrians and vehicular traffic around the project site.
On this particular project, DeMarr Engineering prepared the Traffic Control Plan to allow step repair and replacement in the public right of way, street tree protection, as well as temporary parking restrictions to reserve two parking spaces for construction vehicles to park during construction. The Traffic Control Plan prepared by DeMarr (Figure 9) also included the route of pedestrian traffic around the site, with flaggers proposed as needed, and various required warning signs to warn motorists passing by the project site to be aware of road work ahead.
With our company mission of providing high quality civil engineering solutions to our clients, DeMarr went beyond the traditional permit plan scope with preparing lease area and construction exhibits to the client (Figures 10, 11, & 12). These exhibits conveyed important elevation and renovation location area information with bright highlight colors and easy to read text for the layman to understand. These exhibits reassured the neighboring condo association that noises from construction would not disturb neighboring residents through the shared party wall along the property line.
Figures 10, 11, & 12: Lease Area & Construction Exhibits prepared by DeMarr
If you have a building renovation, addition or new build project in Washington DC, please contact our civil engineers for a quote.