tabaqat.
Energy · Pipeline Integrity
Pipeline Integrity Evidence Pack

Two-thirds of California's regulated liquid pipelines run through ground nobody has mapped.

Not "checked and found safe."
Never evaluated.

707 pipelines · 6,093 measured miles · every figure re-queried live 2026-08-06

tabaqat.
The measurement

One partition. It sums to 100.0 %
with exactly zero miles of overlap.

17.8 %
20.1 %
62.1 %
In a mapped liquefaction zone — 1,086 mi Evaluated, and not zoned — 1,224 mi Never evaluated3,783 mi
3.8×
Unevaluated areas vs mapped zones

The Seismic Hazards Mapping Act programme publishes 2,806 Unevaluated Areas against 738 zone polygons.

1,224
Miles the state looked at and cleared

The good news nobody reports. An authority evaluated this ground and found nothing — a different fact from silence.

62.1 %
Miles no one has looked at

A hazard query returning zero here means "no one has looked", not "no hazard". Only one of those is in the data.

tabaqat.
The framing
Before anything else

This is not a story about operators.

Nobody in industry decides whether the California Geological Survey has evaluated a quadrangle. That is a state mapping programme, with a state budget and a state backlog.

Publishing "X % of this company's mileage is unevaluated" would convert a public-sector data gap into an accusation about a private company's conduct. The per-operator view exists inside the app, where you can see it is a map of the state's coverage. No operator is named in this deck or in the article.

The finding is about the record, not about anybody's behaviour. Nothing here says unsafe, at risk, in violation, or likely to fail — the finding is an absence of evaluation, and the build fails if that language creeps in.

tabaqat.
The instrument

Pipelines are the one asset class
whose world is one-dimensional.

Engineers navigate by station, not by extent. Their native artifact — the alignment sheet — is a horizontal ruler with stacked tracks. So the navigation is the milepost axis, and the map is demoted to a locator that follows it.

1 · Commodity
2 · Diameter
4 · Wall · grade · seam
8 · Baseline / reassessment
13 · Surface fault rupture
14 · Liquefaction

The demo line: 91.05 measured miles, 0.32 mi inside an Alquist-Priolo Earthquake Fault Zone, 3 Quaternary fault crossings — and 100 % of it never evaluated.

tabaqat.
The inversion
What makes it a different product

Each band is painted by the state of the evidence,
not by a value.

Evidencedan authority answered, with a value
Evidenced — hazard present an authority answered, and the answer is a mapped hazard
Evidenced-absent an authority evaluated this ground and found nothing
Never evaluated no authority has looked here
Present, not verifiable the record carries a value that cannot be relied on as filed
Operator-only structurally not public; only the operator's files can fill it

Every filled cell carries the service, the query, the UTC timestamp and the row count that produced it. PHMSA's records standard is traceable, verifiable, complete — a records standard, not a data standard.

tabaqat.
The pack

A §195.452 evidence pack has fourteen lines.
The public record answers three.

✔ Three, from the public record

Commodity · surface fault rupture · liquefaction — the last only partially, because 62.1 % of the network was never evaluated.

Three is the ceiling. The app shows a live per-line count — 5 of 14 on the worked example, where diameter and stationing happen to be reliable. On a line filing 8, 10, 12, or on any of the 145 that are discontinuous, they revert to present, not verifiable.

⛔ Nine, only the operator can fill

Wall thickness, grade, seam type · install year · MAOP · HCA segments · assessment dates · anomaly and dig records · cathodic protection · incident history · the AB 864 risk analysis.

They render empty, with their citation. Drop a CSV keyed on line_id and station_mi and they light up — parsed in the browser, uploaded nowhere, each filled lane naming the file it came from in the pack, the provenance table and the export.

No sample data ships. Each drop zone offers a blank template — a template is a contract; data would be a fabrication.

tabaqat.
Traps

Four ways this data will quietly lie to you.

1 · The object ID is not OBJECTID

The OID is FID — and a separate, non-OID column literally named OBJECTID also exists, and diverges. Select on the obvious one and you highlight the wrong pipeline.

2 · Shape__Length is Mercator metres

Sum it and California has 7,483 miles. Geodesically it has 6,093. That 22.8 % is 1/cos(latitude) — the easiest way to publish a wrong headline.

3 · Diameter is a string with 84 forms

8 · 8" · 8.625 · 8, 10, 12 · whitespace. Not a plain number on 169 lines = 1,723 mi = 28.3 %. Never parsed here.

4 · A third of it has no continuous axis

145 of 707 lines are multipart — 2,019 mi, 33.1 % — with up to 80 parts and a worst gap of 108 miles. The parts carry no order and no measure.

tabaqat.
The design decision
Trap 4 decided the whole app

So the instrument refuses.

A milepost computed as "cumulative distance along the geometry" would silently teleport 108 miles between parts — and every station printed downstream would be wrong.

MP 0 ──10──20──30──40──45.2  ▮ 108.1 mi gap ▮  0 ──10──20──30──40──64.3

One sub-axis per part. The gap labelled in miles. Never concatenated.

An instrument that will not draw a measurement it cannot justify is worth more than one that always produces a number.

tabaqat.
The bug
Told, not hidden

My first pass said the demo line was
~53 % unevaluated. It is 100 %.

try: … except: continue

Five of thirteen polygons failed a validity check, were silently skipped, and the script reported success. The independently-written app disagreed with it — the only reason it was caught.

A bare except in a measurement script is not error handling. It is data corruption that reports success — and it is worse than a crash, because a crash tells you.

Same week, same class: a CSV reader coerced "0274" to 274. Line IDs are zero-padded strings, so every row of an operator's file would have missed its line — silently, reporting a cheerful "0 matched." Identifiers are strings. Only magnitudes are numbers.

tabaqat.
Honest scope

What it is not.

Not a risk score. Likelihood needs wall thickness, age, coating and ILI; consequence needs HCA segments, which are withheld from the public. A red/amber/green score off five public string fields — two of them unreliable — would carry the authority of a risk model with the content of a guess.

Not a filing, and not a compliance determination.

Not anyone's LRS. Stationing is measured along the published 2018 centerline in its digitised direction — the app prints that caveat on the ruler itself.

Not a finding about any company. It is a finding about a record.

Open data · open source · runs on ArcGIS or on-prem. We can render an empty lane with its citation because we have no engine to protect.