NV5 - Legoland


NV5 provided all civil engineering functions for the development of the 128-acre Legoland theme park in Carlsbad, California. The park is divided into 60 acres of “Inner Park” area, 63 acres of “Outer Park” development, and a 5-acre Service/Administration area. The Inner Park includes eight clusters (attraction areas), a three-acre lagoon with associated water features, and two expansion areas for future attractions. The attraction areas are separate, highly detailed productions of exhibits and ride features; all have required a well-coordinated design effort between landscape, hardscape, and utilities. Topographic relief across the Inner Park is approximately 50 feet in 950, resulting in a challenge to ADA standards. The Inner Park is encompassed by a 24 foot service road, which also acts as a corridor for wet and dry utilities. The Outer Park consists of parking for 5,000 vehicles, circulation roadways, and a 2.5-acre detention basin. The Service/Administration area contains a four-building complex of office and maintenance space, and a plant nursery.

NV5 was responsible for coordinating design of grading (2.5 million cubic yards of earthwork), substantial storm drain improvements, private sewer and water systems, reclaimed water systems, Lego Drive public improvements, and entitlement support through the City of Carlsbad. Design challenges included an aggressive schedule to meet the planned opening, quantifying substantial earthwork volumes within complex geotechnical layers (including notoriously poor and compressible soils), intricate routing of utilities in the attraction areas, evaluation of storm runoff, and design of detention basins. The detention basin design was complicated by a California Coastal Commission requirement that required fully developed runoff from a 100-year event be attenuated to a 10-year natural discharge volume.

Included in the design tasks was the design of 2,600 feet of Lego Drive, from Armada Drive to the main entrance of the park. Although Lego Drive is a private roadway, it is designed as a 48 foot wide public roadway, with a series of reversing curves and tangents; and features adjacent mounding of varying heights. The mounding is provided for landscape treatments to give the roadway a unique approach to the park’s main entrance. The infrastructure contained within the roadway alignment consists of sewer, water, and reclaimed water mains, as well as a major 60-inch storm drain. The depth of the storm drain varies to as much as 18 feet which required the installation of deep cleanout structures to 16 feet.


Carlsbad, CA




Key Facts

  • 125+ Acres
  • Earthwork 2.5M cubic yards
  • 2.5 Acre Detention Basin