Recreational use assessment of water-based activities, using time-lapse construction cameras

Abstract

Recreational exposure to surface waters during periods of increased pathogen concentration may lead to a significantly higher risk of illness. However, estimates of elementary exposure factors necessary to evaluate health risk (i.e., usage distributions and exposure durations) are not available for many non-swimming water-related activities. No prior studies have assessed nonswimming water exposure with respect to factors leading to impaired water quality from increased pathogen concentration, such as weather condition (rain events produce increased runoff and sewer overflows) and type of day (heavy recreational periods). We measured usage patterns and evaluated the effect of weather and type of day at eight water sites located within Philadelphia, by using a novel ''time lapse photography'' technology during three peak recreational seasons (May --September) 2008 --2010. Camera observations validated with simultaneous in-person surveys exhibited a strong correlation (R 2 ¼ 0.81 to 0.96) between the two survey techniques, indicating that the application of remote photography in collecting human exposure data was appropriate. Recreational activities usage varied more on a temporal basis than due to inclement weather. Only 14% (6 out of 44) of the site-specific activity combinations showed dry weather preference, whereas 41.5% (17 out of 41) of the combinations indicated greater usage on weekends as compared with weekday. In general, the log normal distribution described the playing and wading duration distribution, while the gamma distribution was the best fit for fishing durations. Remote photography provided unbiased, real-time human exposure data and was less personnel intensive compared with traditional survey methods. However, there are potential limitations associated with remote surveillance data related to its limited view. This is the first study to report that time lapse cameras can be successfully applied to assess water-based human recreational patterns and can provide precise exposure statistics for non-swimming recreational exposures. Keywords: recreational water use; exposure assessment; non-swimming water exposures; time-lapse camera applications; remote photography; exposure duration distributions Journal of Exposure Science and Environmental Epidemiology INTRODUCTIONThe decision to treat (disinfect) wastewater and storm water overflows is a major controversy in the US and will probably cause large cities massive investment in ''gray'' infrastructure to mitigate wet weather discharges. A rational decision would use risk-benefit or cost-benefit approaches. To assess risk, one must know how the waters are being used. Although in many cases where the dominant use is swimming, the quantification of exposure is more straightforward, for example, by using aerial photos, turnstile counts or parking fees and so on. In a context, such as the one described in this paper where non-swimming recreational activities are the principal mode of exposure to surface water bodies, the issue is both determining how ma...

A mechanistic understanding of hyperstability in catch per unit effort and density-dependent catchability in a multistock recreational fishery

“…Several other authors have used time-lapse cameras to assess water-based recreational activities (Smallwood et al 2011;Sunger et al 2012). Cuddeback (Expert Model) cameras were installed at each lake on a tree at the shoreline.…”

The severely under‐recognized public health risk of strongyloidiasis in North American cities—A One Health approach

“…Behaviours involving potential contact with sediment/mud in urban areas (e.g. swimming, wading, bathing/washing, fishing, walking barefoot, fishing, picnicking and collecting trash along shorelines) can potentially result in infection and have been documented in or near urban waterways (Donovan, Unice, Roberts, Harris, & Finley, ; Sunger & Haas, ; Sunger, Teske, Nappier, & Haas, ). We also note that the Baermann technique, which is used to diagnose Strongyloides , involves suspending faecal matter in cloth (“coarse fabric”) and analysing larvae that have migrated through that cloth (Siddiqui & Berk, ).…”

Exploratory Assessment of Risks from Drinking and Recreational Water Exposure to Children in the State of New Jersey

“…For scenario 2, recreational activities included boating, fishing, and swimming (Table 3). These were selected based on reported frequent water exposure activities as well as suggested designated water uses on the Delaware River [2,40]. The scenario assumed a full day of recreation that included all three activities.…”

“…For a worst-case scenario, it was assumed that a full day of recreation occurred once every week for the full recreational season of the year (May-September, 5 months). Exposure duration statistics for fishing and boating were obtained from the study conducted by Sunger and co-authors that specifically observed recreational activities on the Delaware River [40]. However, for swimming, the United States Environmental Protection Agency (EPA) default exposure duration for children less than 6 years of age was considered [41].…”