According to the Visitor Use Capacity and Fee Background document released by BC Parks in February 2020:

Our methodology for identifying a visitor carrying capacity is based on a review of published papers on the topic, recommendations from the International Union for Conservation of Nature, and the United States Visitor Use Management Framework.

The analysis on visitor capacity was based on many sources of information collected in 2019 via surveys, field reports by rangers and park stewards, on-site assessments and attendance data recorded by counters.

To identify the visitor capacity of Joffre Lakes Park, we analyzed the relationship between the number of visitors and the following attributes: visitor experience, perceptions of safety, and environmental impacts.

Given the results of the analysis, a cap on visitation of 1,500 people per day is proposed as it falls in the middle of this visitor capacity analysis. Analysis of attendance trends over the past three years highlights that the proposed capacity would not have a large effect or constriction on weekday use; however, it would reduce the weekend spike in use.