Variable seepage meter efficiency in high-permeability settings
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- More information: Publisher Index Page (via DOI)
- Data Releases:
- USGS data release - Webb and Rosenberry, 2020, MODFLOW 2005 and MODPATH 5 model data sets used to evaluate seepage-meter efficiency in high-permeability settings
- USGS data release - Webb and Rosenberry, 2020, MODFLOW 2005 and MODPATH 5 model data sets used to evaluate seepage-meter efficiency in high-permeability settings
- USGS data release - Seepage meter efficiency in highly permeable settings source data (2020)
- USGS data release - Seepage meter efficiency in highly permeable settings source data (2020)
- Open Access Version: Publisher Index Page
- Download citation as: RIS | Dublin Core
Abstract
The efficiency of seepage meters, long considered a fixed property associated with the meter design, is not constant in highly permeable sediments. Instead, efficiency varies substantially with seepage bag fullness, duration of bag attachment, depth of meter insertion into the sediments, and seepage velocity. Tests conducted in a seepage test tank filled with isotropic sand with a hydraulic conductivity of about 60 m/d indicate that seepage meter efficiency varies widely and decreases unpredictably when the volume of the seepage bag is greater than about 65 to 70 percent full or less than about 15 to 20 percent full. Seepage generally decreases with duration of bag attachment even when operated in the mid-range of bag fullness. Stopping flow through the seepage meter during bag attachment or removal also results in a decrease in meter efficiency. Numerical modeling indicates efficiency is inversely related to hydraulic conductivity in highly permeable sediments. An efficiency close to 1 for a meter installed in sediment with a hydraulic conductivity of 1 m/d decreases to about 60 and then 10 percent when hydraulic conductivity is increased to 10 and 100 m/d, respectively. These large efficiency reductions apply only to high-permeability settings, such as wave- or tidally washed coarse sand or gravel, or fluvial settings with an actively mobile sand or gravel bed, where low resistance to flow through the porous media allows bypass flow around the seepage cylinder to readily occur. In more typical settings, much greater resistance to bypass flow suppresses small changes in meter resistance during inflation or deflation of seepage bags.
| Publication type | Article |
|---|---|
| Publication Subtype | Journal Article |
| Title | Variable seepage meter efficiency in high-permeability settings |
| Series title | Water |
| DOI | 10.3390/w12113267 |
| Volume | 12 |
| Issue | 11 |
| Year Published | 2021 |
| Language | English |
| Publisher | MPDI |
| Contributing office(s) | WMA - Earth System Processes Division |
| Description | 3267, 22 p. |
| Google Analytic Metrics | Metrics page |