Event Title
Influence of waste water treatment plants on water quality and microbiota within Penn Cove.
Presentation Abstract
Anthropogenic point sources, such as waste water treatment plants (WWTP) are often considered as contributors to hypoxic conditions due to nutrient enrichment. Penn Cove, which is located within Whidbey basin of Puget Sound, has been designated as an impaired water body due to chronic low dissolved oxygen (DO). To determine whether the WWTP outfalls in Penn Cove might contribute to low DO, we assessed relationships among physical parameters, dissolved nutrients, and microbial features, such as bacterial community structure and heterotrophic production, both within and outside of Penn Cove. Hyperbenthic DO measurements revealed contrasting monthly patterns with low values in August and November and higher values in February and May. Concentrations of dissolved nutrients varied both temporally and by depth, but concentration patterns were similar regardless of distance from WWTP outfalls. Similarly, abundances of microbial populations, such as total baterioplankton, picophytoplankton, and coccoid cyanobacteria (Synechococcus spp) were associated with sampling month, rather than WWTP outfalls. Linkages of bacterial community structure were found among sampling locations, however the strongest relationships between community structures were seen by season and depth, rather than proximity to WWTPs. The abundances of indicators for human- or bovine-sourced fecal bacteria were positively associated with mean daily flow at the lower Skagit River during the prior month, but not by proximity to WWTP outfalls. Furthermore, total suspended particles and particles with associated bacterioplankton were both correlated with Skagit River flow (Pearson's r > 0.61), suggesting that Penn Cove may be strongly influenced by the Skagit River. WWTP influences on nutrient inputs, microbial abundances, and bacterial community structure appear to be minimal compared to the seasonally driven influences, such as river discharge from the nearby Skagit River.
Session Title
Session S-06C: Water Quality III
Conference Track
Water Quality
Conference Name
Salish Sea Ecosystem Conference (2014 : Seattle, Wash.)
Document Type
Event
Start Date
1-5-2014 1:30 PM
End Date
1-5-2014 3:00 PM
Location
Room 606
Genre/Form
conference proceedings; presentations (communicative events)
Contributing Repository
Digital content made available by University Archives, Heritage Resources, Western Libraries, Western Washington University.
Subjects – Topical (LCSH)
Water quality--Washington (State)--Penn Cove; Water--Dissolved oxygen--Washington (State)--Penn Cove; Sewage disposal plants--Environmental aspects--Washington (State)--Penn Cove; Sewage sludge as fertilizer--Environmental aspects--Washington (State)--Penn Cove
Geographic Coverage
Salish Sea (B.C. and Wash.); Penn Cove (Wash.)
Rights
This resource is displayed for educational purposes only and may be subject to U.S. and international copyright laws. For more information about rights or obtaining copies of this resource, please contact University Archives, Heritage Resources, Western Libraries, Western Washington University, Bellingham, WA 98225-9103, USA (360-650-7534; heritage.resources@wwu.edu) and refer to the collection name and identifier. Any materials cited must be attributed to the Salish Sea Ecosystem Conference Records, University Archives, Heritage Resources, Western Libraries, Western Washington University.
Type
Text
Language
English
Format
application/pdf
Influence of waste water treatment plants on water quality and microbiota within Penn Cove.
Room 606
Anthropogenic point sources, such as waste water treatment plants (WWTP) are often considered as contributors to hypoxic conditions due to nutrient enrichment. Penn Cove, which is located within Whidbey basin of Puget Sound, has been designated as an impaired water body due to chronic low dissolved oxygen (DO). To determine whether the WWTP outfalls in Penn Cove might contribute to low DO, we assessed relationships among physical parameters, dissolved nutrients, and microbial features, such as bacterial community structure and heterotrophic production, both within and outside of Penn Cove. Hyperbenthic DO measurements revealed contrasting monthly patterns with low values in August and November and higher values in February and May. Concentrations of dissolved nutrients varied both temporally and by depth, but concentration patterns were similar regardless of distance from WWTP outfalls. Similarly, abundances of microbial populations, such as total baterioplankton, picophytoplankton, and coccoid cyanobacteria (Synechococcus spp) were associated with sampling month, rather than WWTP outfalls. Linkages of bacterial community structure were found among sampling locations, however the strongest relationships between community structures were seen by season and depth, rather than proximity to WWTPs. The abundances of indicators for human- or bovine-sourced fecal bacteria were positively associated with mean daily flow at the lower Skagit River during the prior month, but not by proximity to WWTP outfalls. Furthermore, total suspended particles and particles with associated bacterioplankton were both correlated with Skagit River flow (Pearson's r > 0.61), suggesting that Penn Cove may be strongly influenced by the Skagit River. WWTP influences on nutrient inputs, microbial abundances, and bacterial community structure appear to be minimal compared to the seasonally driven influences, such as river discharge from the nearby Skagit River.
