1. What is the Local Data Exchange (LDX) process?
The Local Data Exchange is the main opportunity for cities and
counties to provide input into Connect SoCal 2024, Southern
California’s next Regional Transportation Plan/Sustainable
2. Why did SCAG initiate the LDX process?
The input received through the LDX process will help SCAG
generate a Forecasted Regional Development Pattern for Connect
SoCal 2024 that identifies how and where the region will
accommodate anticipated growth. SCAG is mandated by statute to
generate a Forecasted Regional Development Pattern to help meet
required greenhouse gas emissions and Clean Air Act targets and
ensure the region can thrive in the coming decades.
3. What type of information and data did SCAG use in the
preliminary growth projections?
SCAG staff, in consultation with an expert panel, the Population
Reference Bureau, and the Center for Continuing Study of the
California Economy jointly developed a projection of population,
households, and employment for the SCAG region and its six
counties based on demographic and economic data and expert
insights (details can be found
The preliminary projection for households at the jurisdiction and
Transportation Analysis Zone (TAZ) levels is based on data from
general plan capacity retrieved from and updated by local
jurisdictions. The preliminary household growth projection also
uses draft 6th cycle housing element updates to refine its
estimates. In order to help the plan reach statutory targets, the
preliminary household growth projection also prioritizes growth
in four types of Priority Development Areas (though, not
exclusively) and minimizes (but does not preclude) growth in ten
types of Green Region Resource Areas. More information about
these areas can be found in any jurisdiction’s Data/Map Book starting on page 13.
The preliminary growth projections are intended to set Connect
SoCal 2024 on a path toward hitting the statutory greenhouse gas
and air quality goals of the Forecasted Regional Development
4. Does the preliminary household growth forecast include a local
jurisdiction’s Regional Housing Needs Assessment (RHNA)
The preliminary household growth forecast does include housing
element data with the understanding that updates are ongoing and
additional local review is a necessary step.
Connect SoCal 2024 will consider the potential for increased
household growth resulting from the 6th cycle RHNA, housing
element updates and funding programs designed to support their
implementation. The plan will also consider that increased
household growth may or may not be impacted by the ability and
resources to increase development.
5. Who will participate in the LDX process?
The LDX process is a data exchange between SCAG and the 197 local
jurisdictions that are the local land-use authorities in the
region. SCAG relies upon data and information provided directly
by local jurisdictions such as land use and entitlements which
drive growth projections . Since Connect SoCal 2024’s projections
are not a build-out scenario and entitled projects are often
phased over time, SCAG relies on local jurisdictions to assess
the development likelihood and timing of key entitlement projects
as they review growth projections.
Input is considered complete if approved by a planning director
or city manager-level staff using SCAG’s Data Review and
Verification Form. In addition, SCAG collaborates directly with
the subregional councils of government in Orange, Riverside and
San Bernardino counties for outreach and data assistance.
While the LDX process is designed for exchanging certain datasets
between local jurisdictions and SCAG, the public is able to view
LDX’s draft Data/Map Books
online at scag.ca.gov/local-data-exchange.
Connect SoCal 2024’s comprehensive public participation process
is set to begin later in 2022.
6. How do local jurisdictions participate in LDX?
SCAG is asking cities and counties to review data layers relating
a. Land Use
b. Priority Development
d. Resource Areas
e. Geographic Boundaries
f. SCAG’s Preliminary Growth Projections
There are several ways to review this data and provide input:
Request an LDX account
h. Review the Data/Map
i. Complete the
j. Schedule a
one-on-one LDX meeting
Complete the Data Review and Verification Form
7. How can local jurisdictions view the data layers?
The draft Data/Map Books and their dynamic online equivalent on
the LDX portal both include the data layers that are the main
local ingredients to Connect SoCal 2024. This consists of several
layers on which SCAG is seeking updates and corrections, other
layers on which local updates and corrections are optional, and
additional third-party data that relate to regional objectives
and are included for reference.
View Only: The draft Data/Map Books are publicly available
PDF versions of the data specific to each local jurisdiction and
are designed to help local planners better understand the
sources, methodologies and contexts of datasets that will be
integrated into SCAG’s regional plans.
Review/Update: The LDX online portal contains
digital maps of each data layer that local planners can view,
edit, and leave comments and feedback on. Using the portal
requires no GIS knowledge or software installation. It also
allows cities that maintain GIS or data files to securely upload
GIS data layers or ArcGIS Urban completed plans.
Unique jurisdictional login information is provided by
requesting access here. The SCAG LIST team is available for
one-on-one meetings and assistance in using the LDX portal by
meeting here or emailing firstname.lastname@example.org.
SCAG will also accept data or feedback via email in any format.
8. What if a local jurisdiction has corrections or updates or
SCAG welcomes input on and changes to the data due to updates in
local policies, including entitlements and development
agreements. We anticipate that these datasets will require
updates in order to accurately reflect local jurisdictions’
The Data/Map Books and preliminary growth forecast are still in
the draft phase and non-binding at all stages. Local jurisdiction
input is critical in making sure we have the most accurate data
available. Corrections or updates can be submitted through any of
the several ways to provide input outlined in Questions 6 and 7
9. How long will the process take?
On Feb. 23, 2022, SCAG soft-launched the LDX, including the
majority of data elements, along with the Regional Data Platform. The LDX
complete launch took place on May 23, 2022, and included the
planning survey and preliminary growth forecast, also known as
Socioeconomic Data. Input and edits are due by Dec. 2, 2022, in
order to be included in Connect SoCal 2024.
10. Where can I get help with the LDX process?
Email us at email@example.com
for assistance. In addition to providing a more direct,
efficient, and modern link between data, local plans, and SCAG’s
regional plan goals, the Regional Data Platform also
provides a wide range of planning tools and data as well as
custom and off-the-shelf software for local jurisdictions.