Passive Surface Water Flux Meters
Much research in watersheds is aimed at describing spatially distributed processes while telescoping monitoring efforts towards a single point of interest, the watershed outlet.
The need for spatially distributed data in multiple first order streams within a watershed is well recognized, but often not practiced due to cost and practical considerations. We are designing a Passive Surface Water Flux Meter (PSFM) to get better spatial data. The PSFM is a low-cost, flow integrated stream water quality sampler designed to provide estimates of cumulative water and solute fluxes across a stream cross-section over the deployment period (~ 3 to 5 days). The device is composed of sorbent that captures the solute of interest (eg, nitrate, pesticides, hormones) and extracting the sorbent post deployment is used for estimating the cumulative solute flux. Simultaneously, pre-sorbed alcohol tracers are eluted in proportion to streamflow, and provide estimates of water flux. Temporal resolution within a storm is sacrificed in order to get better spatial coverage over the watershed.