Civil Site, Drainage and Floodplain Coordination

What the scope can include

Select the work and handoff your project needs. The agreement identifies the included deliverables and responsibilities.

• Site geometry and earthwork

  Coordinate surveys, boundaries, grading limits, earthwork, building placement and interfaces with adjacent land. Keep field data, proposed elevations and constraints aligned across disciplines.

• Parking, paving and transportation

  Bring parking, loading, driveways, circulation, pavement and roadway interfaces into the package. Larger transportation or civil structures require the applicable specialist design and owner review.

• Drainage and water quality

  Coordinate stormwater collection, conveyance, detention, discharge and water-quality work with the responsible designer. Record off-site connections, maintenance responsibilities and dependencies on receiving-system information.

• Floodplain and construction disturbance

  Track flood-related studies, authority decisions and construction stormwater documentation, including SWPPP/SWP3 scope where applicable. Operational drainage design and construction controls are distinct responsibilities and deliverables.

Prepare for the assignment

You can start with incomplete records. Tell us what is available and what still needs to be established.

• Information to bring

  Current survey and topography, proposed site layout, existing drainage and utilities, available geotechnical information, access constraints and prior civil approvals.

• The agreed handoff

  A coordinated site/civil package, supporting study register and approval dependencies, with unresolved off-site or authority requirements clearly identified.

Decisions, fees and timing

Scope and dependencies determine the proposal. No universal price or approval date is assumed.

1. Confirm the basis and responsibility

   Review the available records, intended endpoint and authority to use the information. Assign missing inputs, technical decisions and the parties who can authorize changes.

2. Coordinate and review the work

   Prepare the included documents from agreed inputs, resolve interfaces with responsible specialists and track revisions. Record external decisions and conditions separately from work prepared for review.

3. Account for project-specific dependencies

   Site size and grades, downstream information, flood-related studies, off-site improvements, earthwork and revision of the building or access layout.

4. Deliver the defined milestone

   Provide the controlling documents and remaining-action record. Identify what is accepted, what still requires a decision and what belongs to a separately contracted next stage.

Choose the access and circulation deliverable

Parking layout, driveway permits, culvert design, traffic studies and swept-path analysis answer different questions. Begin with a survey, property/access rights, roadway ownership and the vehicles and activities the site must serve.

• Parking and turning movements

  A parking layout coordinates spaces, aisles, loading, accessible routes and fire access with grades and drainage. Swept-path analysis checks the space a defined vehicle occupies while turning using agreed vehicle dimensions and movements. Provide delivery, refuse, emergency and customer vehicle needs. The output is a layout or turning exhibit with conflicts identified; it does not measure surrounding traffic capacity.

• Driveway permits and culverts

  Identify which agency controls the road and where private work meets its right-of-way. Driveway exhibits may need location, width, sight-distance information, grades, sidewalks and utility conflicts. A culvert additionally needs drainage-area and flow information, inlet/outlet levels, roadway loads and erosion/maintenance interfaces from the responsible designers. Confirm application and review requirements before choosing a connection detail.

• Traffic study

  Traffic analysis evaluates how a proposal affects travel demand, access or roadway operations within an agreed study area. Supply the operating program, scale, phasing, existing access and available counts. The transportation specialist and authority establish methods, data and mitigation questions. Coordinate the resulting report and recommendations with the site plan; a simple stall layout is a different scope.

Drainage studies, H&H and detention design

A drainage study establishes how existing and proposed runoff can be managed. Bring a current topographic survey, existing drainage records, proposed grading, surface areas and known outfall or downstream constraints.

• Hydrologic and hydraulic analysis

  Hydrologic analysis estimates runoff for the selected rainfall and watershed conditions; hydraulic analysis evaluates how that flow moves through pipes, channels, culverts or storage. Together, H&H can support calculations, models and a drainage report. The designer must establish accepted criteria, survey levels, contributing areas and downstream assumptions with the relevant authority; different projects need different study limits.

• Impervious cover and detention

  An impervious-cover calculation measures existing and proposed roofs, paving and other surfaces under the applicable local definitions. It informs runoff assumptions and any related development review. Detention design, where required or selected, coordinates temporary storage and controlled discharge with grading, outlets, access and maintenance. Neither a new paved area nor a particular label proves a detention facility is always required; confirm the criteria and receiving-system conditions first.

Floodplain records and map-change requests

These documents answer different questions. Start with the property location, effective flood information, survey/elevations, prior determinations and the proposed or completed work. Confirm the required pathway with the local floodplain administrator and responsible specialists.

• Elevation certificate and LOMA

  An elevation certificate records building and elevation information for floodplain/insurance purposes; a qualified preparer must establish the applicable certified information. A Letter of Map Amendment (LOMA) seeks FEMA’s determination concerning a property or structure shown in a mapped hazard area, generally using better natural-ground information. Coordinate the survey and application evidence; the certificate itself does not amend the flood map or grant a building permit.

• CLOMR and LOMR

  A Conditional Letter of Map Revision (CLOMR) concerns the effect of a proposed project on mapped flood information; a Letter of Map Revision (LOMR) is an official revision based on supporting technical data. Coordinate the engineering models, survey, proposed/as-built geometry and community records appropriate to the request. A conditional review is not a final map revision or construction authorization; confirm separate local approvals and any later completed-condition submission.

• No-rise analysis

  A no-rise analysis evaluates a project’s effect on flood levels under the applicable floodway criteria. It needs the accepted existing model, survey, project geometry and qualified hydraulic analysis. The responsible engineer determines the evidence and certification appropriate to local review. Do not substitute an elevation certificate for this analysis or assume an unsupported drawing proves no impact.

• Substantial-improvement review

  For improvement or repair to an existing floodplain building, assemble the scope, cost documentation, valuation information and prior work records requested by the local administrator. The authority evaluates the applicable substantial-improvement rules and resulting design obligations. Coordinate the determination with repair and permit plans; do not infer an exemption from a small-looking work area or assume every community counts costs identically.

Docks, shorelines and dredging coordination

Waterfront work connects property rights, water conditions, structural design and environmental review. Bring the survey, shoreline/access records, existing approvals, proposed dimensions/use and available water-depth and ground information.

• Dock permits and pier plans

  Define fixed or floating construction, intended vessels/users, access, utilities and attachment locations. Coordinate qualified structural, foundation and access design with water-level, wave/current and navigation constraints applicable to the site. The package may include plan/profile exhibits and specialist documents for the relevant owners and authorities. Confirm land/water access rights and agency jurisdictions before treating a dock permit as the only approval.

• Bulkheads and shoreline stabilization

  A bulkhead retains the shoreline through a structural system; shoreline stabilization can involve other engineered or vegetated approaches. Provide erosion history, survey, soils, neighboring features and proposed limits. Specialists compare appropriate approaches and coordinate drainage, structural support, habitat and water interfaces. Document the selected concept, investigations and approvals instead of assuming a wall is the correct solution everywhere.

• Dredging and layers of authority

  Dredging coordination needs the proposed area/depth, material characterization, removal method, access and placement/disposal location. The U.S. Army Corps of Engineers may review navigable-water work under Section 10 and discharges under Section 404; state, local, landowner or reservoir requirements may also apply. Coordinate the actual permit path and specialist exhibits through environmental review below. Design support does not authorize dredging or include every field operation.

Before you begin

Common questions