U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet 2019–3029, ver. 1.1

June 2019

The 3D Elevation Program—Supporting California’s Economy

Introduction

California faces unprecedented challenges presented by shifting weather patterns 

that are defining a “new normal.” The result 

has been extreme weather events, prolonged 

drought, flooding, and debris flows. These 

conditions drive severe tree mortality, increase 

wildfire occurrence and intensity, reduce water 

availability, and hasten subsidence in groundwater basins. Collectively, these challenges 

threaten public safety, compromise infrastructure, and adversely impact the economic 

well-being of California’s citizens. Critical 

applications that address these issues depend 

on light detection and ranging (lidar) data that 

provide a highly detailed three-dimensional 

(3D) model of the Earth’s surface.

The 3D Elevation Program (3DEP; see 

sidebar) works in partnership with Federal, 

State, Tribal, U.S. territorial, and local agencies to acquire consistent lidar coverage at 

quality level 2 or better (table 1) to meet the 

needs of California (Roth, 2018) and the 

Nation. The status of publicly available lidar 

data in California is shown in figure 1. The 

National Enhanced Elevation Assessment 

(NEEA) (Dewberry, 2012) identified user 

requirements and conservatively estimated 

that availability of lidar data would result in 

at least $28 million in new benefits annually 

to the State. The top six California business 

uses for 3D elevation data, which are based on 

the estimated annual conservative benefits of 

3DEP, are shown in table 2.

Table 1. Data quality levels, pulse spacing, 

and pulse density. Quality level 2 or better 

lidar data meet 3DEP requirements.

[Specifications are from Sugarbaker and others 

(2014, table 1). In the quality level column, QL0 

represents the highest level of quality. RMSEz , 

root mean square error in the elevation (z) dimension; cm, centimeter; m, meter; pls/m2

, first return 

pulses per square meter; ≤, less than or equal to; 

≥, greater than or equal to]

Quality 

level RMSEz

Aggregate 

nominal 

pulse 

spacing 

(m)

Aggregate 

nominal 

pulse 

density 

(pls/m2

)

QL0 ≤5 cm ≤0.35 ≥8.0

QL1 ≤10 cm ≤0.35 ≥8.0

QL2 ≤10 cm ≤0.71 ≥2.0

EXPLANATION

Lidar data that meet 3DEP 

requirements (quality 

levels 0, 1, and 2)

Non-3DEP lidar data

No publicly available 

lidar data

100 KILOMETERS

0 100 MILES

0

Figure 1. Map of California showing the 

areal extent and quality levels of existing 

and in-progress publicly available lidar data 

as of June 2019. Quality level 2 or better lidar 

data meet 3DEP requirements. See table 1 for 

quality level information.

Infrastructure and Construction 

Management

California has approximately $187 billion in unmet infrastructure needs: $50 billion 

in flood management, $59 billion in deferred 

highway maintenance, and $78 billion in local 

streets and roads (The Planning Report, 2017).

Using lidar data reduces the time required 

for project planning, resulting in cost savings. 

Lidar data can be used for preliminary highway 

alignment and design and for estimating earthwork quantities, evaluating existing roadway 

conditions, and identifying safety projects. 3D 

elevation data can also (1) help to improve 

compliance with building and environmental 

regulations, (2) enhance the evaluation of 

project sites, (3) provide input to hydrologic 

and hydraulic modeling to improve the design 

of structures (bridges and culverts), and (4) be 

integrated with geologic and engineering data 

to expedite project review and reduce costs.

Flood Risk Management

California’s proposed four-point plan 

(The Planning Report, 2017) to bolster dam 

safety and flood protection can benefit from 

lidar data that support more accurate and less 

expensive hydrologic and hydraulic modeling 

for flood studies, retention-dam design, dam 

breach studies, and stormwater management 

and engineering. This information can be used 

to identify vulnerable properties within a flood 

plain, facilitate better flood-plain-management 

decisions, and educate the public on flood 

risk zones by providing dynamic 3D models 

to show the potential impact of flooding from 

major storm events.

Wildfire Management, Planning, and 

Response

In recent years, California has experienced record-setting wildfires and subsequent 

debris flows triggered after heavy rain events. 

In addition to the tragic loss of life, more 

than 24,000 homes and structures have been 

destroyed, inflicting tremendous human and 

financial losses. Up-to-date lidar data are used 

to map the buildup of potentially dangerous 

biomass fuels in wildland/urban interface areas 

(fig. 2). The high-resolution 3D elevation data 

support fire behavior modeling, fire response, 

vegetation-load appraisal, and post-fire assessment for slope instability, leading to improved 

public safety.

Geologic Resource Assessment and 

Hazard Mitigation

Geologic mapping and mineral assessment can be performed more efficiently and 

accurately using lidar data. The California Geological Survey’s annual production summary 

reported the top five nonfuel mineral commodities in 2016 were construction sand and gravel, 

portland cement, boron minerals, crushed 

stone, and soda ash, with a total production 

value of $3.4 billion. Aggregate materials are 

essential to maintain the existing infrastructure 

and to provide for new construction.

Lidar-derived digital terrain models, 

and derivative products such as slope, aspect, 

contour, profile, and shaded relief, inform 

the development of regulatory zones and the 

assessment and planning related to hazards 

such as faults, landslides, tsunamis, and 

flooding.

3DEP by the Numbers: California

Expected annual benefits $28.16 million

Estimated cost for quality 

level 2 completion

$22.95 million

Payback 0.81 years

Quality level 1 buy-up 

estimate

$50.37 million
Table 2. Conservative benefits estimates 

for the top six California business uses of 

the proposed 3DEP data identified in the 

National Enhanced Elevation Assessment 

(Dewberry, 2012).

Rank Business use

Annual 

benefits 

(millions)

1 Infrastructure and construction management$8.37

2 Natural resources 

conservation

4.37

3 Flood risk management 4.22

4 Wildfire management, 

planning, and 

response1 

4.02

5 Agriculture and precision 

farming

2.01

6 Geologic resource 

assessment and hazard 

mitigation

1.66

Other 3.51

Total 28.16

1

In the years since the release of the National 

Enhanced Elevation Assessment (Dewberry, 2012), 

it is likely that the benefits estimate for wildfire 

management, planning, and response has increased.

Figure 2. Images derived from lidar point-cloud 

data. Left, perspective view showing tree canopy 

height (color) overlying bare earth (gray). Right, 

profile view showing forest vegetation structure. Colors in both images represent elevation above 

the ground surface; the lowest level of vegetation is shown in dark blue. Warmer colors indicate 

higher elevation. Images courtesy of Robert McGaughey, U.S. Forest Service (left) and Van R. Kane, 

University of Washington (right).

References Cited

Dewberry, 2012, Final report of the National 

Enhanced Elevation Assessment (revised 

March 29, 2012): Fairfax, Va., Dewberry, 

84 p. plus appendixes, accessed July 

31, 2018, at http://www.dewberry.com/

services/geospatial/national-enhancedelevation-assessment.

Roth, Nathaniel, 2018, California lidar―A 

critical investment: California Department 

of Conservation story map, accessed October 4, 2018, at http://cadoc.maps.arcgis.

com/apps/Cascade/index.html?appid=4a63

a54438f74d5db21114bec266baf4.

Sugarbaker, L.J., Constance, E.W., 

Heidemann, H.K., Jason, A.L., Lukas, 

Vicki, Saghy, D.L., and Stoker, J.M., 2014, 

The 3D Elevation Program initiative—A 

call for action: U.S. Geological Survey 

Circular 1399, 35 p., accessed July 31, 

2018, at http://dx.doi.org/10.3133/cir1399.

The Planning Report, 2017, Gov. Brown 

prioritizes California’s water and transportation infrastructure spending: The 

planning report―Insider’s guide to 

planning and infrastructure, February 

28, 2017, accessed July 31, 2018, at 

https://www.planningreport.com.

3D Elevation Program (3DEP)

The 3D Elevation Program is managed by the U.S. Geological Survey (USGS) 

on behalf of Federal, State, local, and other 

partners and users of elevation data. The 

goal of 3DEP is to complete the acquisition 

of light detection and ranging (lidar) data 

(interferometric synthetic aperture radar 

(IfSAR) data in Alaska) in 8 years to provide 

the first-ever national baseline of consistent, high-resolution elevation data.

Benefits

• Economies of scale by acquiring data 

for larger areas.

• Predictable and flexible Federal investments that reduce costs and allow 

better planning.

• Consistent national coverage that 

provides data for applications that span 

project, jurisdictional, and watershed 

boundaries.

• Simplified data acquisition that provides 

contracts, project management, quality 

assurance, and published data specifications.

• National benefits of $690 million per 

year conservatively, with the potential 

to generate $13 billion per year in additional benefits through applications that 

span the economy (Dewberry, 2012).

High-Quality Data and Products

3DEP lidar provides coverage with 

a minimum of two points per square 

meter and a vertical error not to exceed 

10 centimeters, measured as root mean 

square error in the elevation (z) dimension 

(RMSEz

) (see table 1). Lidar data products 

include all data points collected (point 

cloud) and a bare-earth digital elevation model with a 1-meter resolution. The 

USGS integrates the elevation data into 

The National Map. Data are available 

free of charge and without use restrictions. To download 3DEP products visit 

https://viewer.nationalmap.gov/basic/.

Ways to Participate

3DEP participation is open to Federal, 

State, Tribal, U.S. territorial, and local 

government partners, as well as private 

sector partners, and offers the option to 

acquire higher quality data. Partners may 

contribute funds toward projects managed 

by the USGS, or they may receive cooperative funds to manage their own projects. 

An annual Broad Agency Announcement is the mechanism used to establish 

partner agreements. Organizations and 

the private sector may contribute existing 

data that meet 3DEP requirements. For 

more information see the 3DEP website at 

https://usgs.gov/3DEP/collaborate.

Learn More About 3DEP

See the websites in the 3D Elevation Program 

sidebar and below. Please send questions to:

Director, National Geospatial Program

U.S. Geological Survey, MS 511

12201 Sunrise Valley Drive

Reston, VA 20192

Email: 3DEP@usgs.gov

—By Carol L. Ostergren, Drew Decker, 

and William J. Carswell, Jr.

USGS National Map Liaisons:

Carol Ostergren; Email: costergren@usgs.gov 

Drew Decker; Email: ddecker@usgs.gov 

https://usgs.gov/3DEP

ISSN 2327-6916 (print)

ISSN 2327-6932 (online)

https://doi.org/10.3133/fs20193029