In urban areas with high amounts of impervious land cover, stormwater basins provide a valuable service by trapping and slowly infiltrating excess runoff which would otherwise impair streams. Stormwater basins also trap fine sediment suspended by runoff, which can lead to clogging of pore spaces needed for proper infiltration and cause the basin to fail. Basins require maintenance, but a thorough understanding of basin behavior is needed to find appropriate maintenance strategies. The goal of this study was to use multiple techniques – electrical resistivity tomography (ERT), ground-penetrating radar (GPR), sediment sampling, soil moisture sensors, and water level loggers – to assess stormwater basin failure and aid in the creation of targeted basin maintenance strategies. Three basins were selected for monitoring based on size and age: the Upper Moreland Middle School Basin (or “Betz”), the Ethel Jordan Memorial Park Basin, and the Lukens Park Basin. Five to six sediment cores were collected from each basin from depths down to 40 cm. Sediment data did not provide evidence for a layer of fine sediment at the basin surface. Basin sediments did not show consistent patterns with depth: Betz coarsened with depth, Ethel Jordan was relatively homogeneous, and Lukens fined with depth. Sediment at Betz and Lukens fined across the basin from inlet to outlet, but sediment from Ethel Jordan was more uniform across the basin. ERT was able to demonstrate differences in resistivity between the basins, as well as structure beneath the basins. The technique was most useful at Lukens, where buried stormwater chambers were identified, and Ethel Jordan, where rocky, high-resistivity portions of the basins were mapped. GPR used at Ethel Jordan showed strong reflected signals from the same region that displayed high resistivity values, helping to confirm the location of the subsurface features. Neither technique was able to demonstrate sediment heterogeneity. Time-lapse ERT surveying was employed at Betz to detect infiltration during storms. However, changing water levels and conductivity values made data inversion difficult and obfuscated any signal from infiltration. Furthermore, it was not apparent that any infiltration was occurring at Betz. Recession rates from water ponded in the basin were more rapid in the summer than in the winter, and were higher in Betz than in Ethel Jordan. Recession at Lukens was not calculated because the basin did not store water due to a broken riser pipe. Soil moisture sensors placed within basin were used to calculate infiltration rates. Rates could only be calculated at Lukens Park, as the subsurface was saturated at Betz and Ethel Jordan. The sensors demonstrated heterogeneity in infiltration rates throughout the basin and the adjacent land surface, as well as lower infiltration rates caused by vegetation. Basins showed no signs of failure based on the results of the monitoring techniques used, but did demonstrate variations in infiltration and recession behavior. While a concise maintenance plan could not be created, this study demonstrated the advantages of multiple monitoring techniques that can be used to improve maintenance strategies. / Geology
| Identifer | oai:union.ndltd.org:TEMPLE/oai:scholarshare.temple.edu:20.500.12613/6812 |
| Date | January 2021 |
| Creators | Collins, Kyle Jonathan |
| Contributors | Toran, Laura E., Nyquist, Jonathan, Davatzes, Alexandra K. |
| Publisher | Temple University. Libraries |
| Source Sets | Temple University |
| Language | English |
| Detected Language | English |
| Type | Thesis/Dissertation, Text |
| Format | 164 pages |
| Rights | IN COPYRIGHT- This Rights Statement can be used for an Item that is in copyright. Using this statement implies that the organization making this Item available has determined that the Item is in copyright and either is the rights-holder, has obtained permission from the rights-holder(s) to make their Work(s) available, or makes the Item available under an exception or limitation to copyright (including Fair Use) that entitles it to make the Item available., http://rightsstatements.org/vocab/InC/1.0/ |
| Relation | http://dx.doi.org/10.34944/dspace/6794, Theses and Dissertations |
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