Walnut Valley, Diamond Bar, CA Violent Crime Rates and Maps
Walnut Valley is a neighborhood of 38,100 residents in Diamond Bar, close to downtown · Updated November 2026
How common is violent crime in Walnut Valley?
Violent crime in Walnut Valley is a little lower than in most US neighborhoods: an A, safer than the neighborhoods where 64% of Americans live. Assaults make up 82% of it, and most of those are simple assaults, which involve no weapon and no serious injury. Diamond Bar as a whole grades A for violent crime.
A
Violent crime CrimeGrade™
Safety score 906 of 1,000Less violent crime than most US neighborhoodsi What this means
64% of Americans live in neighborhoods with more violent crime than Walnut Valley as a whole, and 36% in neighborhoods with less. The typical US neighborhood has a violent crime safety score of 860, a CrimeGrade™ of A. Walnut Valley scores 906.
Crime is concentrated in a small share of places, so most neighborhoods score high on the 0 to 1,000 scale. That is why a score in the 800s can still mean more violent crime than most US neighborhoods.
How to read the map: each area's color compares its violent crime with the people who spend time there, on one national scale, from green for the least to red for the most. Each area gets its own color, so a busy downtown or nightlife strip can show red while the homes around it stay green. The interactive maps load faster on a solid connection. Compare high speed internet in Walnut Valley, Diamond Bar, CA at ISP Reports.
Who this page is for: homeowners and renters in Walnut Valley in Diamond Bar, and anyone thinking about buying or renting a home there.
Business and enterprise customers: this free map shows neighborhood areas. CrimeGrade™ business reports map crime at about 66-meter detail and estimate it for one address and type of business. See business reports
What stands out about violent crime in Walnut Valley
Simple assault runs low. Walnut Valley has 2.0 simple assaults a year per 1,000 residents, a small fraction of the US rate of 9.7.
Where violent crime is lowest and highest in Walnut Valley
Every part of Walnut Valley where people live grades A or B for violent crime on the national scale. Violent crime grades across Walnut Valley run from A+ to A-.
100%
A or B 100%
Share of residents, by the violent crime CrimeGrade™ of the area they live in.
Is violent crime going up in Diamond Bar?
Reported violent crime in Diamond Bar as a whole has fallen 41% since 2019. Murders, rapes, robberies and aggravated assaults went from about 1.3 to 0.8 a year per 1,000 residents (US: 3.7). In 2024 alone, violent crime fell 43%.
Violent crime, change since 2019
Diamond BarUnited States
Source: crime reports to the FBI from the police departments that serve Diamond Bar. The charts follow crimes per resident.
Data table
Year
Violent, Diamond Bar
Violent, US
2016
-10%
+4%
2017
-22%
+4%
2018
-20%
+0%
2019
+0%
+0%
2020
-13%
+4%
2021
+19%
+6%
2022
+34%
+5%
2023
+3%
+2%
2024
-41%
-4%
Violent crime rates and types in Walnut Valley
CrimeGrade™ estimates Walnut Valley has about 3.5 reported violent crimes a year for every 1,000 residents, 74% less than the US as a whole and 36% more than Diamond Bar as a whole.
All violent crime
Assaults
Robbery
Reported crimes a year, per 1,000 residents. Violent crime here includes simple assaults, which the FBI's violent crime rate leaves out.
Assault is the most common violent crime in Walnut Valley, about 82% of the total.
Each CrimeGrade™ here compares a violent crime with the people who spend time in an area, not only the people who live there. Rates count crimes per 1,000 residents.
Select a crime's name to see its map above. CrimeGrade™ business reports map each crime at about 66-meter detail.
Violent crime in Walnut Valley and nearby neighborhoods
Walnut Valley has less violent crime than 9 of its 10 nearest neighborhoods; only Brea-Olinda has less.
Nearest first, with each place's distance from Walnut Valley. Beside each violent crime CrimeGrade™ is its safety score, from 0 to 1,000 (higher is safer).
Compared with neighborhoods of similar size and density, Walnut Valley is safer than 93% of them.
Among the traits that tend to go with violent crime, two set Walnut Valley apart: it has 80 jobs for every 100 residents, against 45 for the US as a whole, and 0.1 bars and nightlife spots for every 1,000 residents, against 0.6 nationally. Places with many jobs tend to report more robbery; here robbery sits near the national middle.
JobsJobs draw daytime crowds. Places with many jobs tend to report more robbery.80 for every 100 residentsUS: 45Higher than for 83% of residents of US city neighborhoods
Walk GradeBestNeighborhood's grade for getting through daily life on foot, traced along real walking routes to shops, schools and parks. Walkable places tend to report more assault. 87% of residents here live in car-dependent areas.D (15 of 100)US: 21Lower than for 82% of residents of US city neighborhoods
Residents in dense blocksBlocks of 10,000 or more people per square mile. Dense neighborhoods tend to report more robbery.20% of residentsUS: 24%Lower than for 81% of residents of US city neighborhoods
Show all 4
Bars and nightlifeBars, lounges, clubs and casinos. Places with more bars tend to report more assault and robbery.0.1 per 1,000 residentsUS: 0.6Lower than for 80% of residents of US city neighborhoods
These traits tend to go with more or less crime; none of them causes it on its own. Sources: Census job counts and housing figures, OpenStreetMap and Overture business listings, CrimeGrade™ parking estimates, NASA night-light imagery, US Forest Service tree cover, EPA transit data and BestNeighborhood's Walk Grade.
What violent crime costs Walnut Valley
Counting the pain and suffering of victims, violent crime costs Walnut Valley about $20 million a year, or $523 per resident. The costs that reach a bill, such as medical care, lost work and the justice system, come to about $4.0 million, or $104 per resident.
Billed cost of violent crime per resident, per year
How CrimeGrade™ works
The violent crime CrimeGrade™ covers murder, rape, robbery and assault, from A+ for the least crime to F for the most, on one scale for the whole country.
It weighs each violent crime against the people who spend time in an area, so a busy downtown is graded on its workers and visitors as well as its residents.
The rates on this page count crimes for every 1,000 people who live here, the way police departments report them.
Comparisons with US neighborhoods use the Census Bureau's block groups, small areas of about 1,400 residents, and count the people who live in each. The figures count crimes reported to police; many crimes, shoplifting above all, never are. Behind the grades, CrimeGrade™ tested 21,607 factors from 125 data families. For business owners, paid CrimeGrade™ location reports estimate crime at a single address for each type of business.
Where the numbers come from
Crime reports that police departments file with the FBI
State crime records and city crime data, where they are published
Published research on what crime costs victims and communities
These are estimates of reported crime for whole areas, not a record of what happened on any one street. CrimeGrade™ updates them once a year and provides them free and without guarantee. Check local sources before you rely on them for a decision.
