I think California DOT tracks collisions and has at least some sort of algorithm to decide when to make changes. Scary looking link to guidelines. https://fhw

I think California DOT tracks collisions and has at least some sort of algorithm to decide when to make changes. Scary looking link to guidelines. https://fhwaapps.fhwa.dot.gov/hsipp/Attachments/aa343eab-2cb8-474a-9101-8fc3d012c440_2017%20STATE%20HSIP%20GUIDELINES%20FINAL.pdf https://fhwaapps.fhwa.dot.gov/hsipp/Attachments/aa343eab-2cb... That said I looked at the intersection on google maps. Here it would have have had a stop sign at least or fixed decades ago.