![\"615ml](\"https:\/\/www.solinst.com\/onthelevel-news\/wp-content\/uploads\/2026\/07\/615ml.jpg\")
<\/a>In a recent study published in Hydrological<\/a> Processes<\/a>, a team of researchers from the University of Iowa and the U.S. Geological Survey (USGS) used a novel tool\u2014the Solinst Model 615ML Multilevel Drive-Point Piezometer<\/strong><\/a>\u2014to tackle these challenges.<\/p>\n\n\n\n The research team, led by Jessica R. Meyer<\/a>, selected Muddy Creek in east-central Iowa as their field site. Muddy Creek is a well-studied, temperate-region effluent-dominated stream (EDS) where treated wastewater effluent contributes most of the stream’s total discharge during low-flow periods.<\/p>\n\n\n\n Because wastewater inputs create rapid, diurnal fluctuations in stream stage, the site represents a highly dynamic and complex hydrological environment. The field instrumentation needed to meet specific criteria:<\/p>\n\n\n\n To overcome these environmental hurdles, the team deployed Solinst 615ML Multilevel Drive-Point Piezometers (DP-MLS). These piezometers scale down the proven design of the Waterloo Multilevel System, allowing up to 6 depth-discrete ports to be threaded onto small-diameter (1.9 cm) stainless steel drive-point riser pipes (3\/4\u201d NPT). Each screened port has a barb for connecting sample tubing that runs to the surface.<\/p>\n\n\n\n For the Muddy Creek study, the researchers configured custom 2-port and 4-port systems utilizing High-Density Polyethylene (HDPE) tubing selected specifically for its chemical compatibility with PFAS and organic contaminants. They were installed at two different sites along the river, with two 2-port systems and one 4-port system at each location.<\/p>\n\n\n Installation was completed manually on-site. The team first used a standard single-interval Solinst drive-point piezometer to “probe” the bed, identifying a geological transition zone based on driving resistance\u2014moving from the loose, sandy sediments of the Camp Creek Member into the more compacted Gunder Member. Using this stratigraphic data, they built and customized the port depths of the Multilevel Drive-Point Piezometers directly in the field from the bottom up, before driving the completed systems to their target depths with a simple 7 kg slide hammer.<\/p>\n\n\n\n To protect the internal tubes during installation, the team used a Solinst drive head with a tubing bypass, ensuring that the internal lines emerged unharmed and exactly at their design depths. Through field testing, it was found that installing with a temporary casing helped prevent ports from being clogged in clay and silt conductions.<\/p>\n\n\n Each study site also included two standard drive-point piezometers, a drive-point stilling well for measuring stream stage, and stream bank monitoring wells equipped with pressure transducers that collected data every 5 min. Data from the standard drive-point piezometers and stilling wells provided temporal context for data collected from the DP-MLS.<\/p>\n\n\n\n Over a comprehensive 2-year monitoring campaign, the DP-MLS proved its excellent structural durability, surviving rapid water stage changes, floating debris, and river ice.<\/p>\n\n\n\n Beyond its ruggedness, the system yielded vital insights into how emerging contaminants interact with local groundwater:<\/p>\n\n\n\n The high-resolution head profiles measured from the DP-MLS revealed that vertical hydraulic gradients varied significantly in magnitude and direction with depth. Traditionally, researchers only measure head from a single depth, assuming a uniform gradient.<\/p>\n\n\n\n By measuring multiple depth-discrete intervals from a single system with a unified reference point and a Solinst Model 102 Narrow Water <\/strong><\/a>Level<\/a><\/strong> Meter<\/strong><\/a>, the team avoided lateral errors. The DP-MLS showed that conventional clustered piezometers underestimated the upward gradient by 2 to 3 times and completely missed critical localized downward gradients.<\/p>\n\n\n Groundwater sampled via a peristaltic pump connected to the DP-MLS lines mapped how far wastewater contaminants traveled into the stream bed:<\/p>\n\n\n\n The University of Iowa and USGS study demonstrates that understanding the fate of contaminants of global concern requires highly precise, high-resolution physical and chemical data.<\/p>\n\n\n\n The Solinst Multilevel Drive-Point Piezometers <\/strong>proved to be an ideal solution for this shallow, dynamic ecosystem. They combine the rugged portability needed for manual river-bed installations with the multi-port capability required to accurately profile complex chemical and hydraulic boundaries. For groundwater professionals and limnologists investigating hyporheic exchange, the DP-MLS represents a reliable path forward for high-resolution subsurface characterization.<\/p>\n\n\n\n To learn more about how to configure Multilevel Drive-Point Piezometer System for your next streambed or shallow monitoring project, visit our <\/em>product page<\/em><\/strong><\/a> or <\/em>contact<\/a><\/em><\/strong> a Solinst technical representative.<\/em><\/p>\n\n\n\n <\/p>\n","protected":false},"excerpt":{"rendered":"The Challenge: Monitoring a Flashy, Effluent-Dominated Stream<\/strong><\/h2>\n\n\n\n
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The Solution: Solinst Multilevel Drive-Point Piezometers<\/strong><\/h2>\n\n\n\n
<\/a><\/a>High-Resolution Field Insights<\/strong><\/h2>\n\n\n\n
1. Unmasking True Hydraulic Gradients<\/strong><\/h3>\n\n\n\n
<\/a>2. PFAS and Pharmaceutical Penetration<\/strong><\/h3>\n\n\n\n
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<\/a>The Takeaway<\/strong><\/h2>\n\n\n\n