Stormwater, Drainage and Flood Risk

How stormwater, drainage and flood-risk design differs on a data center site, and where to start reading.

The problem this page addresses

Stormwater design on a data center campus differs from ordinary commercial development in three ways that change the civil engineering.

Impervious coverage is very high. Buildings, generator yards, transformer pads, security roads and parking leave little pervious surface, so runoff volume and peak rate are large relative to the site area.

The site has to stay operational and accessible in extreme events. Drainage is not only about meeting a discharge limit. Access roads for fuel delivery, emergency response and maintenance need to remain passable, and critical equipment pads need to stay above the design flood level.

Utility corridors constrain where water can go. Power, fiber and water routes are fixed early and are difficult to move, so the drainage design has to work around a utility layout that is often already committed.

What RSP Engineers does on these sites

RSP's scope is the civil site engineering:

  • Stormwater management design — conveyance, detention and retention, outfall design and discharge permitting.
  • Grading and earthwork design that sets pad elevations relative to the design flood level.
  • Drainage for access roads, including routes intended to remain passable during a design storm.
  • Coordination of drainage with the utility corridors and easements crossing the site.
  • Permitting support with the local drainage authority, the water management district or equivalent, and federal agencies where wetlands are involved.

Scope boundaries

RSP Engineers performs the civil site engineering described above and also provides mechanical, electrical and plumbing engineering through its own licensed staff. Where a project uses both, the interfaces between building systems and site infrastructure are designed together. Structural engineering and the other project disciplines deliver their own scopes, and how a completed facility performs — its energy use, the redundancy of its systems, its availability in service — depends on the owner's requirements, the equipment selected, the serving utilities, the construction and how the facility is operated. It is not determined by any single discipline's design.

Related reading

The 66 articles RSP Engineers has published on this subject, grouped by question. Titles are as published.

Modeling and analysis

Floodplain and extreme events

Ponds, storage and infiltration

Conveyance, outfalls and easements

Water quality, erosion and construction

Cost, strategy and permitting

Other data center pathways

Related services

Discuss a site

If you are evaluating or developing a data center site, tell us about the project and we will come back to you about the civil scope.