By Brian Brady, COO and VP Business Development, Gistic Research, Inc.

Going from unvalidated GIS data to NG9-1-1 readiness isn’t simply a matter of working through an error list.

The order matters.

A point error may actually originate with a road. A road error may originate with a boundary. And an attribute error may simply be the downstream symptom of geometry that hasn’t been corrected yet.

That’s why our basic approach follows one dependency:

Boundaries → Lines → Points → Content

Fix the upstream condition first, and a surprising amount of the downstream cleanup becomes easier.

So what does a realistic six-month path look like?

Weeks 1–2: Establish the Baseline

The agency’s data is loaded as it exists today.

It doesn’t need to be completely restructured before anyone can begin working. Existing fields can be mapped to the required model while preserving the local attributes other departments still depend on.

Then comes the first validation.

The report may be long. That’s normal.

Hundreds or even thousands of findings shouldn’t be surprising in a dataset that has never been evaluated for NG9-1-1 routing.

But instead of starting at the top of the error list and working downward, the first validation should answer a more useful question:

Where are the concentrations of problems, and what upstream dependencies are creating them?

Milestone

Data loaded. Staff trained. Baseline established.

Weeks 3–6: Boundaries First

Before correcting thousands of road or address attributes, we need confidence in the geography those attributes describe.

Start with the boundaries:

• Administrative boundaries
• PSAP boundaries
• Emergency service boundaries
• Provisioning boundaries
• Legacy ESN/MSAG community boundaries where applicable

First, correct intra-layer then inter-layer issues such as gaps, overlaps, slivers, and improperly closed polygons to establish common edges.

Then look at the relationships between layers and across neighboring jurisdictions.

This is also where collaboration becomes important.

You can’t maintain one side of a shared boundary as though the other side doesn’t exist.

A neighboring agency doesn’t have to surrender control of its data, but its geometry needs to be visible so both organizations are working against the same spatial reality.

Milestone

The authoritative boundary framework is spatially reliable.

Weeks 7–10: Make the Roads Respect the Boundaries

Once the boundary framework is trusted, the next dependency is the road network.

Road centerlines need to be examined wherever they cross a boundary that affects attribution.

That can include incorporated communities, unincorporated communities, neighborhood communities, legacy ESN/MSAG communities, and other relevant jurisdictional or service boundaries.

If crossing the boundary changes the meaning of the road segment, the RCL should be broken there.

The sequence is simple:

Validate the boundary. Find the crossing. Split the road. Then attribute the new segments.

This avoids spending time correcting attributes on an RCL that shouldn’t exist as one continuous feature in the first place.

Once the segmentation is correct, authoritative boundary values can be spatially overlaid against the road network.

In GIVE, our Topology workflow can use those authoritative layers to populate or batch-correct the proper left- and right-side administrative values on the RCL.

When A1 through A5 boundary layers are available, the workflow becomes:

Authoritative polygon → Spatial overlay → RCL left/right attribution

That’s much more efficient than asking an analyst to manually correct hundreds or thousands of road records.

Milestone

Roads are correctly segmented and attributed from authoritative geography.

Weeks 11–14: Stabilize the Road Network

Now the road features are in the right condition for deeper topology and normalization.

Check the RCL network for:

• gaps
• overlaps
• dangles
• self-intersections
• roads not properly broken at intersections
• other structural conditions

Then normalize the content.

This is where street-name parsing, controlled domains, A3i, ranges, and other administrative normalization become much more productive.

The important point is that we’re now normalizing road segments whose geometry and relationship to the surrounding geography are already correct.

That reduces rework.

Milestone

The road network is structurally stable and normalized.

Weeks 15–18: Roads to Address Points

Only after the road network is stable do we make point-to-road relationships a major focus.

Each address point should be associated with the appropriate road-centerline segment.

This is where the fishbone becomes particularly useful.

A fishbone connects the address point to the location where that address should dynamically fall along the associated road segment based on the low and high ranges for that side.

That simple graphic can expose a lot:

• The point may be associated with the wrong road.
• The range may not contain the address.
• The point and road may disagree on administrative values.
• The road may still have a segmentation problem.

Instead of reading an error code and trying to imagine what’s wrong, the analyst can see the relationship.

Once the correct association is established, appropriate attributes can be transferred or reconciled.

Then the relationship is synchronized, which re-evaluates and builds or updates the fishbone based on the corrected ranges and attributes.

The workflow becomes:

Associate → Review → Correct → Synchronize

Milestone

Address points are associated with stable RCLs and their relationships are synchronized.

Weeks 19–21: Resolve What Remains

Now we’re in the best position to deal with the remaining content-validation findings.

This is where many cleanup projects begin.

I think it’s where they should end.

By this point:

• boundaries are reliable
• roads are properly segmented
• authoritative administrative values have been propagated
• road topology has been cleaned
• street names have been normalized
• address points have been associated
• fishbones have been synchronized

The findings that remain are much more likely to be genuine content problems rather than symptoms of unresolved geometry.

That’s the difference between simply fixing red dots and understanding why they turned red.

Milestone

Remaining findings are isolated content issues, not unresolved structural dependencies.

Weeks 22–25: Synchronize and Provision

Most agencies won’t shut off their legacy systems overnight.

For some period of time, the NG9-1-1 GIS and legacy MSAG/ALI environment will coexist.

Those systems need to agree.

The goal isn’t just to reconcile them once.

It’s to keep them from drifting apart again.

Then the GIS can be validated against the actual requirements of the state or NG9-1-1 provider and prepared for downstream publication and provisioning.

At this stage, the validation should look very different from the first run.

Why?

Because the major dependencies have already been addressed in the right order.

Milestone

Data validated, synchronized, and ready for provisioning.

Week 26 and Beyond: Keep It Clean

The final phase isn’t really about cleanup.

It’s about proving the workflow.

A subdivision gets built.

A street is renamed.

An address is added.

A community annexes property.

A neighboring jurisdiction changes a shared boundary.

The system should identify the impact while those changes are happening.

Because if you spend six months clearing a backlog and then return to the process that created it, you haven’t solved the problem.

You’ve postponed it.

Compliance ultimately needs to become:

Not a certificate. Not an annual report. Not a project.

A condition maintained every day.

What Can Stretch the Timeline?

Technology can’t eliminate every dependency.

• A neighboring agency isn’t participating. Shared-boundary reconciliation can’t always be completed unilaterally.
• The provider’s provisioning cadence is slow. Missing a monthly submission window can add time no software can recover.
• Address points don’t exist. Building a usable point layer is real GIS work.
• The legacy MSAG hasn’t been maintained. Synchronization becomes much harder after years of divergence.

These aren’t reasons not to start.

They’re reasons to understand the starting point before putting a date on the calendar.

The Bigger Point

The six-month timeline is useful, but the more important lesson is the order.

Don’t manually correct downstream attributes that can be derived from authoritative upstream geography.

Fix the geography.

Establish relationships.

Let the system propagate what it already knows.

Then resolve what remains.

That gives us a much more logical NG9-1-1 GIS workflow:

Boundaries ↓ Road segmentation ↓ Authoritative left/right attribution ↓ Road normalization ↓ Address association ↓ Synchronize ↓ Remaining content QC ↓ Provisioning

It also reduces one of the most frustrating parts of GIS cleanup:

fixing the same problem more than once.

Everything I’ve described reflects the direction we’ve taken with GIVE, but the larger principle isn’t about a particular software product.

It’s about recognizing that NG9-1-1 GIS is a connected spatial system.

A point depends on a line.

A line depends on the geography around it.

And validation findings are often symptoms of those relationships.

So instead of asking:

“How many errors do we have?”

I think the better question is:

“Which upstream conditions are creating them?”

Solve those first, and the rest of the work gets a lot easier.

Brian Brady is COO and VP of Business Development at Gistic Research, Inc. Gistic has been developing collaborative GIS and data-quality solutions for public agencies since 2005. Brian writes regularly about NG9-1-1 GIS standards, data quality, collaboration, and the practical realities of moving from legacy GIS workflows into continuously maintained NG9-1-1 environments.