3DEP in New Hampshire by the Numbers

Expected annual benefits $1.68 million 

Estimated total cost $3.09 million*

Payback 1.8 years

Quality level 1 buy-up 

estimate

$1.97 million

 *State-estimated acquisition 

cost (2014)

 $2.0 million

U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet 2014–3110 

January 2015

The 3D Elevation Program—Summary for New Hampshire

Introduction

Elevation data are essential to a broad 

range of applications important to New 

Hampshire, including flood mitigation, land 

development, agriculture, transportation planning and design, infrastructure asset inventory 

and management, and many others. For the 

State of New Hampshire, elevation data are 

critical for many business uses such as flood 

risk management, natural resources conservation, forest resources management, agriculture and precision farming, infrastructure 

and construction management, and geologic 

resource assessment and hazard mitigation. 

Today, high-density light detection and ranging (lidar) data are the primary sources for 

deriving elevation models and other datasets. 

Federal, State, Tribal, and local agencies work 

in partnership to (1) replace data that are older 

and of lower quality and (2) provide coverage 

where publicly accessible data do not exist. 

A joint goal of State and Federal partners is 

to acquire consistent, statewide coverage to 

support existing and emerging applications 

enabled by lidar data. 

The National Enhanced Elevation 

Assessment (NEEA; Dewberry, 2011) 

evaluated multiple elevation data acquisition 

options to determine the optimal data quality 

and data replacement cycle relative to cost to 

meet the identified requirements of the user 

community. The evaluation demonstrated that 

lidar acquisition at quality level 2 (table 1) for 

the conterminous United States and quality 

level 5 interferometric synthetic aperture 

radar (ifsar) data (table 1) for Alaska with a 

6- to 10-year acquisition cycle provided the 

highest benefit/cost ratios. The 3D Elevation 

Program (3DEP) initiative (Snyder, 2012a,b) 

selected an 8-year acquisition cycle for the 

respective quality levels. 3DEP, managed 

by the U.S. Geological Survey (USGS), the 

Office of Management and Budget Circular 

A–16 lead agency for terrestrial elevation 

data, responds to the growing need for highquality topographic data and a wide range 

of other 3D representations of the Nation’s 

natural and constructed features.

3D Elevation Program Benefits 

for New Hampshire

The top 10 New Hampshire business 

uses for 3D elevation data, which are 

based on the estimated annual conservative 

benefits of the 3DEP initiative, are shown in 

table 2. The NEEA survey respondents in the 

State of New Hampshire estimated that the 

national 3DEP initiative would result in at 

least $1.68 million in new benefits annually 

to the State. The cost for such a statewide 

program in New Hampshire is approximately 

$3.1 million, resulting in a payback period of 

1.8 years and a benefit/cost ratio of 4.3 to 1 

over an 8-year period. In 2014, the State estimated a lidar acquisition cost of $2.0 million 

(Rick Chormann, written commun., April 16, 

2014) to complete the statewide coverage (see 

figure 1 to identify areas currently without 

lidar data). Because monetary estimates were 

not provided for all reported benefits, the total 

benefits of the 3DEP to New Hampshire are 

likely much higher. On the basis of the NEEA 

survey results, all levels of government 

and many organizations in New Hampshire 

3D Elevation Program

3DEP is a national program managed 

by the USGS to acquire high-resolution 

elevation data. The initiative is backed by a 

comprehensive assessment of requirements 

(Dewberry, 2011) and is in the early stages 

of implementation. 3DEP will improve 

data accuracy and provide more current 

data than is available in the National 

Elevation Dataset (NED). The goal of this 

high-priority cooperative program is to 

be operational by early 2015, and to have 

complete coverage of the United States 

by the end of 2022, depending on funding 

and partnerships. 3DEP can conservatively 

provide new benefits of $1.2 billion/year 

and has the potential to generate $13 billion/year in new benefits through improved 

government services, reductions in crop 

and homeowner losses resulting from 

floods, more efficient routing of vehicles, 

and a host of other government, corporate, 

and citizen activities (Dewberry, 2011). A 

shared, common elevation dataset would 

foster cooperation and improve decisionmaking among all levels of government and 

other stakeholders.

Benefits of a Funded National Program

• Economy of scale—Acquisition of 

data covering larger areas reduces 

costs by 25 percent.

• A systematic plan—Acquisition of 

data at a higher quality level reduces 

the cost of “buying up” to the highest 

levels needed by State and local 

governments.

• Higher quality data and national 

coverage—Ensure consistency for 

applications that span State and watershed boundaries and meet more needs, 

which results in increased benefits 

to citizens.

• Increase in Federal agency contributions—Reduces State and local partner 

contributions.

• Acquisition assistance—Provided 

through readily available contracts and 

published acquisition specifications.

Figure 1. Map of New Hampshire showing 

the extent of existing and planned publicly 

available lidar data. Information source is 

the United States Interagency Elevation 

Inventory, October 2014 (http://coast.noaa.

gov/inventory/?redirect=301ocm#), which is 

updated annually. Quality level 2 or better 

data meet 3DEP requirements. See table 1 

for quality level information. 

EXPLANATION

Quality level 2 

or better data

Quality level 3

data

No publicly available

lidar data

0 15 30 Kilometers

0 10 20 Miles
Next Steps for Implementing 3DEP

Accomplishing the 3DEP initiative’s 

goal of national coverage in 8 years depends 

on the following factors:

• Increased partnerships among Federal, 

State, Tribal, and local governments. 

• Partnerships that acquire elevation data 

to the program’s specifications across 

larger project areas.

• Increased communication about and 

awareness of the program’s benefits 

and goals.

• Support for the program from government and other stakeholders.

For Further Information:

Director, 

USGS National Geospatial Program

12201 Sunrise Valley Drive, MS 511

Reston, VA 20192

Email: 3DEP@usgs.gov

Lester (Lin) I. Neifert, 

 The National Map Liaison

331 Commerce Way, Suite #2, MS 510

Pembroke, CT 03275

Email: lineifert@usgs.gov

http://nationalmap.gov/3DEP/

By William J. Carswell, Jr.

could benefit from access to statewide highresolution elevation data.

For New Hampshire, approximately 

78 percent of the identified business use 

requirements will be met in flood risk management and natural resources conservation 

uses, as shown in table 2. The status of publicly available lidar data in New Hampshire is 

shown in figure 1. By enhancing coordination 

between 3DEP and various government and 

private organizations in New Hampshire, it 

may be possible to realize more than the cited 

conservative benefits and attain the higher 

potential benefits for many business uses.

The following examples highlight 

how 3DEP data can support business uses 

in New Hampshire: (1) Lidar data provide 

high-quality terrain information as input for 

more accurate and less expensive hydrologic 

and hydraulic modeling for flood studies; 

for the design of structures, such as bridges 

and culverts, to accommodate runoff and 

flooding from large rain events (fig. 2); and 

for retention dam design, dam breach studies, 

and stormwater management and engineering. Lidar data also aid the identification of 

vulnerable properties within a floodplain, 

facilitating better floodplain-management 

decisions and education of the public on true 

flood risks, potentially resulting in avoided 

costs during flood events. Dynamic 3D 

models show the potential impact of flooding. 

(2) Enhanced elevation data could enable 

State, regional, and local governments to 

more effectively implement natural resources 

conservation practices, such as grade 

stabilization, dam safety, habitat easements, 

pipelines, terracing, and wetland restoration, 

while providing additional cost savings to 

the public. If lidar data were available, public 

and private organizations would expand 

their use of lidar for planning and site-level 

engineering to reduce field work for conservation projects.

References Cited

Dewberry, 2011, Final report of the National 

Enhanced Elevation Assessment (revised 

2012): Fairfax, Va., Dewberry, 84 p. 

plus appendixes, http://www.dewberry.

com/Consultants/GeospatialMapping/

FinalReport-NationalEnhancedElevation

Assessment.

Snyder, G.I., 2012a, National Enhanced 

Elevation Assessment at a glance: U.S. 

Geological Survey Fact Sheet 2012–3088, 

2 p., http://pubs.usgs.gov/fs/2012/3088/.

Snyder, G.I., 2012b, The 3D Elevation 

Program—Summary of program 

direction: U.S. Geological Survey 

Fact Sheet 2012–3089, 2 p., http://

pubs.usgs.gov/fs/2012/3089/.

ISSN 2327-6932 (online)

http://dx.doi.org/10.3133/fs20143110

3D Elevation Program—Continued

The USGS and its partners will 

acquire quality level 2 or better (table 1) 

3D lidar data over the conterminous United 

States, Hawaii, and the U.S. territories. 

Interferometric synthetic aperture radar 

(ifsar) data are being collected at quality 

level 5 (table 1) in Alaska. The data will 

be acquired over an 8-year period and 

will be made available to the public. By 

using this acquisition scenario a number of 

high-quality elevation-data products can be 

created to serve a wide range of business 

uses in government and the private sector.

Figure 2. Cold River flood damage to 

State Route 123 (Witcomb Road) bridge 

and road near Drewsville, New Hampshire, 

on October 10, 2005. Watershed and 

hydraulic models and analyses using lidar 

data-derived digital elevation models 

can help reduce flood risks from large 

rain events. Courtesy of New Hampshire 

State Police.

Table 2. Conservative benefits estimates for the top 10 business uses of the proposed

3DEP data identified in the National Enhanced Elevation Assessment for New Hampshire

 (Dewberry, 2011).

Rank Business use Annual benefits

(thousands)

1 Flood risk management $925.2

2 Natural resources conservation 379.9

3 Forest resources management 93.3

4 Agriculture and precision farming 70.3

5 Infrastructure and construction management 67.7

6 Geologic resource assessment and hazard mitigation 50.1

7 Aviation navigation and safety 32.4

8 Coastal zone management 25.6

9 Sea level rise and subsidence 23.4

10 River and stream resource management 3.8

Other 5.6

Total 1,677.3

Table 1. Data quality levels and related 

accuracies for the 3D Elevation Program 

(3DEP) initiative are provided on page 6 in 

USGS Circular 1399 (http://dx.doi.org/10.3133/

cir1399 ). These data quality parameters for 

the 3DEP initiative approximate those used in 

the National Enhanced Elevation Assessment 

(Dewberry, 2011).

[RMSE(z), root mean square error in the z

(elevation) dimension; n/a, not applicable]

Quality 

level

Nominal pulse 

spacing

(meters)

Vertical error 

as RMSE(z)

(centimeters)

1 0.35 10

2 0.7 10

3 2.0 20

4 n/a 139

5 n/a 185