Sepulveda Basin Crime Rate Trends — Los Angeles
Sepulveda Basin is the flood-control basin behind Sepulveda Dam in the central San Fernando Valley — a 2,000-acre recreation area containing Lake Balboa, the Sepulveda Basin Wildlife Reserve, the Woodley Park golf courses, and the Sepulveda Basin Sports Complex. Almost no residential population in the polygon itself.
April 2026 was a narrow month in Sepulveda Basin — a single below-trend signal across all tracked categories. One category moved, one direction: down.
Other larceny is the sole tracked signal, running below its multi-year baseline with 10 incidents in the current 12-month window against 23 in the prior year, a 56.5% decline. The broader 12-month picture reinforces the pattern: every category in the summary is down year-over-year — theft from vehicle off 40.0%, vandalism off 42.1%, aggravated assault off 51.9%, motor vehicle theft off 58.3%, burglary off 60.0%. None of those triggered a signal this month, which means the declines are holding without fresh movement.
Notable signals 1
Other Larceny
The past 12 months saw 10 incidents — about 58% below the 24 average from prior years.
All categories, last 24 months
Each panel: recent monthly count vs. trailing 12-month context. MoM is the most recent month vs. the one before; 12mo YoY compares the trailing year to the year before that.
What's been quietly true for a year
Spikes get attention. Sustained shifts shape policy. These are multi-quarter patterns where the past 12-month total differs meaningfully from the year before — they often precede the baseline resetting.
No sustained shifts surfaced this month.
What next month likely looks like
Forecasts trained through April 2026, with a likely range we're 95% confident the actual count will fall inside. Categories with too little recent volume — or violent categories at the neighborhood level — show no forecast and are surfaced through signals above instead. See the methodology page for the gating rules.
Aggravated Assault
Too low-volume per neighborhood for a reliable point forecast — see the rare-event and streak-break signals above instead.
Arson
Below the volume threshold for a reliable forecast — too few incidents in recent months to project from.
Burglary
Below the volume threshold for a reliable forecast — too few incidents in recent months to project from.
Homicide
Too low-volume per neighborhood for a reliable point forecast — see the rare-event and streak-break signals above instead.
Motor Vehicle Theft
Below the volume threshold for a reliable forecast — too few incidents in recent months to project from.
Other Larceny
Below the volume threshold for a reliable forecast — too few incidents in recent months to project from.
Robbery
Too low-volume per neighborhood for a reliable point forecast — see the rare-event and streak-break signals above instead.
Sexual Assault
Too low-volume per neighborhood for a reliable point forecast — see the rare-event and streak-break signals above instead.
Theft from Vehicle
Vandalism
How Sepulveda Basin compares
Peer neighborhoods picked by closest 12-month other larceny volume — a pragmatic v1 of peer matching. Demographic / housing-stock peer matching isn't built yet (we deliberately don't ingest income or race data alongside crime). Volume similarity has the right intuition: “neighborhoods experiencing comparable other larceny levels.”
Elysian Valley
12 incidents over the past 12 months — 2 above Sepulveda Basin's 10.
Open page →Hansen Dam
5 incidents over the past 12 months — 5 below Sepulveda Basin's 10.
Open page →Lake View Terrace
15 incidents over the past 12 months — 5 above Sepulveda Basin's 10.
Open page →Do crime spikes here spill over to adjacent neighborhoods?
When Sepulveda Basin has spiked vandalism historically (8 events on record), an adjacent neighborhood spiked the same category within 3 months 100% of the time. The strongest-travelling categories sit at the top of the table.
| Category | Spike events | Same-category spillover |
|---|---|---|
| Theft from vehicle | 12 | 0% |
| Aggravated assault | 10 | 10% |
| Vandalism | 8 | 100% |
| Other larceny | 6 | 100% |
| Burglary | 2 | — too few |
Each row shows Sepulveda Basin's historical spike events for that category, and how often any of its 5 adjacent neighborhoods spiked the same category within the next 3 months. A high same-category rate suggests a shock that travels (e.g. theft crews moving across Los Angeles); a low rate means spikes here tend to be local to the neighborhood. Categories with fewer than 5 historical spike events are listed but their rates are suppressed.
Recurring local terms (last 12 months)
Top terms in incident descriptions for Sepulveda Basin, excluding generic crime taxonomy. Useful as texture — what kinds of specifics show up here that don't show up elsewhere.
Hour-of-day, day-of-week, and seasonality
Distribution of bucketed incidents in this neighborhood across the full analysis window. Useful for routine context — shopping-strip thefts vs. late-night assaults read very differently when you can see when each typically happens.
How we built this page
Counts from March 2024 onwardrun roughly 10 to 20 percent below LAPD's command-staff totals citywide. LAPD's legacy crime feed froze after a late-2024 cyber incident, and the replacement NIBRS feed has been shipping fewer rows than LAPD's own statistics show. The shortfall is most visible in homicide and in dense south-LA neighborhoods, because the new feed lacks coordinates and resolves location through reporting districts. Trend direction is still meaningful; absolute levels are not directly comparable to LAPD's headline figures.
Data → Anomalies → Forecast → Page
Incident data is pulled from LAPD's open feed on the LA City Open Data portal — the NIBRS-coded feed from 2024-03 onward with UCR backfill to 2020. Mapped to 10 NIBRS-aligned categories and aggregated to neighborhood × category × month.Anomalies are surfaced using strict thresholds (~p < 0.01). Forecasts are Prophet with low-count gating; violent categories at the neighborhood level skip the forecast and show rare-event / streak signals instead.
Spike rule: 12-mo total > baseline mean + 2.5σ AND ≥ 20 incidents AND 6-mo confirms. Drop rule: 12-mo total < baseline mean − 2.5σ AND baseline mean ≥ 20. Rare event: any incident in the last 90 days, no prior comparable in ≥ 5 years.