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Frequently Asked Questions (FAQ)

These questions and answers will be updated as new information becomes available over time. The questions are focused on creating partnerships for acquisition, but as the process moves along, will address data access, use and training.

Lidar Data Quality Levels

What is QL?

QL stands for Quality Level. See the handout - Why 3DGeo Supports QL1

What are QL0, QL1, QL2 and QL3?

These are value levels related to the quality of lidar data the USGS has defined based on factors in the following table.

LBSAggregate nominal pulse spacing and density
Absolute vertical accuracy
Minimum digital elevation model cell size
Supported Contour Interval
Quality Level

Aggregate nominal pulse spacing (m)

Aggregate nominal pulse density (pls/m2)
RMSEz (nonvegetated) (m)
NVA at the 95% confidence level (m)
VVA at the 95 percentile (m)
Minimum cell size (m)
Minimum cell size (ft)
In Feet

LBS - Lidar Base Specification (USGS 2020 rev. A) RMSEz - root mean square error in the z direction; NVA - nonvegetated vertical accuracy; VVA - vegetated vertical accuracy

Lidar Data Acquisition Deliverables and Costs

What data and products will we get if we contribute to 3DEP?

What are Possible Added Deliverables?

Possible Added Deliverables (not 3DEP-funded deliverables, but can be part of the 3DEP contract as additional products and services with the 3DEP contract vendor)

What are Foundational Derived Products?

Foundational Derived Product (Publicly available data served as authoritative products from state agency distribution portals)

What will this cost my organization?

The cost will vary by LAA based on how many partnerships can be found and the number of counties participating. The larger the contiguous area, the cheaper it will be. The more partners, the cheaper it will be for each partner. Initially, we will provide a cost range based on other current projects. As the project moves along, the USGS will provide the 3D Geomatics Committee with a per mile cost that we will share with you.

Coordination | Minnesota's Committee-based Lidar Acquisition

What is the Minnesota Geospatial Advisory Council?

The Minnesota Geospatial Advisory Council (GAC) acts as a coordinating body for the Minnesota geospatial community. It represents a cross-section of organizations that include counties, cities, universities, business, nonprofit organizations, federal and state agencies, tribal government, surveyors, and other stakeholder groups that benefit from geospatial technology.

What is the 3D Geomatics Committee?

The 3D Geomatics Committee (3DGeo) is a committee chartered under the Minnesota Geospatial Advisory Council (GAC). The 3D Geomatics Committee is committed to identifying and promoting the need for planning, training, funding, acquisition, and management of three-dimensional geomatic data and derived products for Minnesota.

Who are 3DGeo Members?

The committee members are stakeholders just like you, in search of funds for lidar.

The committee created a plan for the state of Minnesota, to work with stakeholders like you, state, county, tribal and city governments. The committee members have expertise in lidar data standards, communication with vendors and Minnesota's Master Contract, big data management and dissemination, the USGS 3DEP Plan, GIS/Lidar education, building stakeholder involvement, development of foundational and authoritative datasets distributed from state servers for everyone to access and use, etc.

Whose plan is this?

The architecture of 3DGeo (pdf) brings dozens of stakeholders together to serve common goals under one Geospatial Advisory Council charter. Membership of 3DGeo is comprised of subject matter experts organized by workgroup sectors. Each workgroup operates by the guidance of its own work plan. Workgroup members specialize in data development, management, dissemination, application, and end user business needs.

Coordination | Minnesota Lidar Acquisition

What is an LAA?

Lidar Acquisition Area

What is a LAB?

Lidar Acquisition Blocks are subareas of certain Lidar Acquisition Areas (not all LAAs have LABs)

Why have you divided the state into Lidar Acquisition Areas (LAA)?

A statewide lidar collection within the same time frame or window is not feasible, but the LAAs:

Whose plan is this?

This is not a plan BY the State of Minnesota, it is a plan FOR the state of Minnesota. This plan was developed by a Committee with several members across all levels of government and the private sector IN Minnesota FOR Minnesota. Feedback on the Plan content and additions/contributions to the Case Studies included in the Plan are welcomed by all.

What is the goal of this plan?

Collect high density lidar at QL1 in every part of the state over the course of several years, in tandem with the USGS 3DEP plan.

Why QL1?

To meet and exceed the USGS's minimum high-quality data standards to ensure the broadest base of end-user applications and higher return on investment for all. QL1 enables the creation of several high quality derived datasets, including:

Coordination | Federal Lidar Acquisition

What is 3DEP?

The 3D Elevation Program (3DEP) is a U.S. Geological Survey (USGS) National Geospatial Program that is systematically guiding the collection of 3D elevation data in the form of light detection and ranging (lidar) data for the United States, and the U.S. territories.

What is BAA?

Broad Agency Announcement (BAA) is the grant coordinating mechanism for the 3D Elevation Program (3DEP). It guides partnerships between the US Geological Survey (USGS) and other Federal agencies with other public and private entities seeking high-quality 3D lidar elevation data acquisition.

Federal agencies, state and local governments, tribes, academic institutions and the private sector are eligible to submit proposals through the BAA process.

Applicants may contribute funds toward a USGS lidar data acquisition activity or they may request 3DEP funds toward a lidar data acquisition activity where the requesting partner is the acquiring authority

What is SeaSketch?

SeaSketch is an online spatial mapping platform developed by the Marine Science Institute at the University of California Santa Barbara. SeaSketch is designed to be customized to allow different stakeholders to use it for planning and monitoring through an interactive web map. Leveraging partnerships in this collaborative mapping platform eliminates redundant efforts, coordinates funding, schedules, priorities, specifications, and sensors to ensure the acquisition of lidar data serves the greatest amount of business needs. We have created a handout to assist you in adding your area of interest to SeaSketch. You can also just look to see what agencies are interested in collaborating in your area.


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