Botts dots and raised pavement markers (RPMs) look superficially similar -- both sit on the road and both delineate lanes -- but they belong to different generations of traffic engineering. Botts dots are a 1960s-era ceramic non-reflective marker invented in California; RPMs are the modern retroreflective successor. For most Oregon parking lots in 2026, RPMs are the answer; Botts dots are increasingly a legacy product even in their state of origin.
Quick verdict
| Use case | Best choice |
|---|---|
| Modern parking lot, mild winter | RPM (raised reflective) |
| Snow-region lot | Snowplowable RPM (flush, cast-iron carrier) |
| Indoor garage with low headlight need | Botts dots acceptable (rare) |
| California legacy retrofit | RPM replacement |
| Tactile-only application (no headlights) | Botts dots possible, RPMs preferred |
What is a Botts dot?
A Botts dot is a small ceramic dome marker, typically 4 inches in diameter and 0.7 inches tall, anchored to pavement with bituminous adhesive. It is non-reflective by design -- the white ceramic body is intended to provide a tactile and visual daylight cue rather than headlight retroreflection. Botts dots were invented in the 1960s by Caltrans engineer Elbert Botts as a low-cost lane-line supplement and were used heavily across the western US for decades. California Department of Transportation (Caltrans) is the original specifying agency.
What is an RPM?
A raised pavement marker (RPM) is a small retroreflective device, typically 4 in by 4 in by 0.7 in tall, anchored to pavement with bituminous or epoxy adhesive. It has one or two retroreflective lenses that return headlight light to the driver. RPMs are governed by ASTM D4280 and used per MUTCD Section 3B.11.
Why is California phasing out Botts dots?
Caltrans began phasing out Botts dots starting in the late 2010s for two reasons:
- No retroreflectivity. Federal retroreflectivity rules (FHWA pavement marking retroreflectivity policy) increasingly demand minimum nighttime brightness on lane lines. Botts dots cannot deliver retroreflectivity.
- Snowplow vulnerability. Ceramic Botts dots shatter under plow blades. As northern California ranges and the Sierras moved toward more aggressive winter maintenance, the ceramic body became a liability.
The replacement program installs raised reflective markers, often paired with thermoplastic line striping for additional wet-night visibility.
Side-by-side comparison
| Attribute | Botts dot | RPM |
|---|---|---|
| Body material | Ceramic | Polycarbonate, ABS, or cast-iron carrier |
| Reflective | No | Yes (one or two lenses) |
| Wet-night visibility | None | High |
| Tactile cue | Yes | Yes |
| Snowplow rated | No | Yes (flush snowplowable type) |
| MUTCD use | Limited (non-retroreflective supplement) | Section 3B.11 retroreflective supplement |
| Typical lifespan | 3 to 6 years | 2 to 5 years (raised) / 5 to 7 years (flush) |
| Cost per marker installed | $2 to $5 | $3 to $9 (raised) / $14 to $28 (snowplowable) |
| Adhesive | Bituminous per ASTM D4796 | Bituminous (asphalt) or epoxy (concrete) |
When does a Botts dot still make sense?
Rarely, for parking lots. The remaining cases:
- Indoor garage where headlight reflection is irrelevant
- Aesthetic install where the white ceramic dome is preferred for appearance
- California legacy retrofit where the property owner is matching adjacent lots
- Slow-speed loop on private property with no rain or night use
For all other cases, RPMs deliver superior wet-night visibility at comparable cost.
Real Cojo install reference
In a Eugene apartment-complex re-striping project in February 2026, the property had a mix of original 1990s Botts dots along the main loop. Most had cracked or shattered from years of plow passes. We replaced them with raised reflective RPMs at 40-foot spacing along the loop and snowplowable flush RPMs at the entry-exit drives where the lot's plow contractor turns the blade. The total marker count was 88 markers replacing 64 Botts dots; the property added wet-night visibility for the first time in the lot's history.
Cost comparison
Industry Baseline Range
| Type | Range (per marker, installed) |
|---|---|
| Ceramic Botts dot | $2 to $5 |
| Raised reflective RPM | $3 to $9 |
| Snowplowable flush RPM | $14 to $28 |
Current Market Reality
Botts dot pricing has stayed flat as ceramic supply chains stabilized; RPM pricing has risen modestly with polycarbonate cost. The cost gap is small enough that the wet-night visibility advantage of RPMs justifies the upgrade in nearly all parking-lot cases.
What about replacement for an existing Botts dot install?
When existing Botts dots are damaged, do not replace in kind. Use the opportunity to retrofit to RPMs at the same locations. The bituminous adhesive footprint is similar enough that the milling work is minor. We cover full removal-and-replace technique in our pavement marker removal and replacement walkthrough.
For deeper context on ceramic versus plastic body materials see ceramic vs plastic pavement markers.