Long-Term Interannual and Seasonal Links between the Nutrient Regime, Sestonic Chlorophyll and Dominant Bluegreen Algae under the Varying Intensity of Monsoon Precipitation in a Drinking Water Reservoir

Long-term variations in reservoir water chemistry could provide essential data in making sustainable water quality management decisions. Here, we analyzed the spatiotemporal variabilities of nutrients, sestonic chlorophyll-a (CHL-a), nutrient enrichment, dominant algal species, and overall chemical water health of the third-largest drinking water reservoir in South Korea during 2000–2020. Our results distinctly explained the strong influence of monsoon rainfall on spatial and annual water chemistry variations. We observed a consistent increase in the chemical oxygen demand alluding to organic matter pollutants, while a steady declining trend in the sestonic CHL-a. The long-term total phosphorus (TP) level showed a steady reduction from the riverine zone to the lacustrine area. However, a higher total coliform bacteria (TCB) was observed at the water intake tower sites. TP displayed a strong link to algal CHL-a and ambient nitrogen phosphorus ratios, suggesting a robust phosphorus-limitation state. The severe phosphorus-limitation was also corroborated by the findings of trophic state index deviation. The high and low flow dynamics exhibited the strong influence of intensive rainfall carrying many nutrients and sediments and flushing out the sestonic CHL-a. Successive eutrophic conditions prevailed along with dominating blue-green algae species (Microcystis and Anabaena). We observed a strong positive correlation (r = 0.62) between water temperature and CHL-a and between total suspended solids and TP (r = 0.65). The multi-metric water pollution index characterized the overall water quality as ‘good’ at all the study sites. In conclusion, the long-term spatiotemporal variabilities of the ecological functions based on the nutrient-CHL-a empirical models are regulated mainly by the intensive monsoon precipitation. The drinking water could become hazardous under the recurrent eutrophication events and chemical degradations due to uncontrolled and untreated inflow of sewage and wastewater treatment plant effluents. Therefore, we strongly advocate stringent criteria to mitigate phosphorus and organic pollutant influx for sustainable management of Daecheong Reservoir.

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Seasonal Water Quality and Algal Responses to Monsoon-Mediated Nutrient Enrichment, Flow Regime, Drought, and Flood in a Drinking Water Reservoir

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph182010714 ◽

2021 ◽

Vol 18 (20) ◽

pp. 10714

Author(s):

Md Mamun ◽

Usman Atique ◽

Ji Yoon Kim ◽

Kwang-Guk An

Keyword(s):

Water Quality ◽

Drinking Water ◽

Flow Regime ◽

Nutrient Enrichment ◽

Water Reservoir ◽

Reservoir Water ◽

Chl A ◽

Drought And Flood ◽

Drinking Water Reservoir

Freshwater reservoirs are a crucial source of urban drinking water worldwide; thus, long-term evaluations of critical water quality determinants are essential. We conducted this study in a large drinking water reservoir for 11 years (2010–2020). The variabilities of ambient nutrients and total suspended solids (TSS) throughout the seasonal monsoon-mediated flow regime influenced algal chlorophyll (Chl-a) levels. The study determined the role of the monsoon-mediated flow regime on reservoir water chemistry. The reservoir conditions were mesotrophic to eutrophic based on nitrogen (N) and phosphorus (P) concentrations. An occasional total coliform bacteria (TCB) count of 16,000 MPN per 100 mL was recorded in the reservoir, presenting a significant risk of waterborne diseases among children. A Mann–Kendall test identified a consistent increase in water temperature, conductivity, and chemical oxygen demand (COD) over the study period, limiting a sustainable water supply. The drought and flood regime mediated by the monsoon resulted in large heterogeneities in Chl-a, TCB, TSS, and nutrients (N, P), indicating its role as a key regulator of the ecological functioning of the reservoir. The ambient N:P ratio is a reliable predictor of sestonic Chl-a productivity, and the reservoir was P-limited. Total phosphorus (TP) had a strong negative correlation (R2 = 0.59, p < 0.05) with the outflow from the dam, while both the TSS (R2 = 0.50) and Chl-a (R2 = 0.32, p < 0.05) had a strong positive correlation with the outflow. A seasonal trophic state index revealed oligo-mesotrophic conditions, indicating a limited risk of eutrophication and a positive outcome for long-term management. In conclusion, the Asian monsoon largely controlled the flood and drought conditions and manipulated the flow regime. Exceedingly intensive crop farming in the basin may lead to oligotrophic nutrient enrichment. Although the reservoir water quality was good, we strongly recommend stringent action to alleviate sewage, nutrient, and pollutant inflows to the reservoir.

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Long-term improvement in surface water quality after land consolidation in a drinking water reservoir catchment

Soil and Water Research ◽

10.17221/108/2013-swr ◽

2016 ◽

Vol 10 (No. 1) ◽

pp. 49-55 ◽

Cited By ~ 1

Author(s):

M. Dumbrovský ◽

V. Sobotková ◽

B. Šarapatka ◽

R. Váchalová ◽

R. Pavelková Chmelová ◽

...

Keyword(s):

Water Quality ◽

Drinking Water ◽

Surface Water ◽

Water Reservoir ◽

Surface Water Quality ◽

Land Consolidation ◽

Drinking Water Reservoir

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Turning Routine Data into Systems Insight: Multivariate Analysis of Water Quality Dynamics in a Major Drinking Water Reservoir

Environmental Modeling & Assessment ◽

10.1007/s10666-020-09700-2 ◽

2020 ◽

Vol 25 (4) ◽

pp. 565-579

Author(s):

Azadeh Golshan ◽

Craig Evans ◽

Phillip Geary ◽

Abigail Morrow ◽

Zoe Rogers ◽

...

Keyword(s):

Water Quality ◽

Drinking Water ◽

Multivariate Analysis ◽

Water Reservoir ◽

Routine Data ◽

Drinking Water Reservoir

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Sediment record of mining legacy and water quality from a drinking-water reservoir, Aztec, New Mexico, USA

Environmental Earth Sciences ◽

10.1007/s12665-020-09126-9 ◽

2020 ◽

Vol 79 (17) ◽

Author(s):

Johanna M. Blake ◽

Jeb E. Brown ◽

Christina L. Ferguson ◽

Rebecca J. Bixby ◽

Naomi T. Delay

Keyword(s):

Water Quality ◽

Drinking Water ◽

New Mexico ◽

Water Reservoir ◽

Sediment Record ◽

Drinking Water Reservoir

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Field Research on Mixing Aeration in a Drinking Water Reservoir: Performance and Microbial Community Structure

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph16214221 ◽

2019 ◽

Vol 16 (21) ◽

pp. 4221 ◽

Cited By ~ 5

Author(s):

Zizhen Zhou ◽

Tinlin Huang ◽

Weijin Gong ◽

Yang Li ◽

Yue Liu ◽

...

Keyword(s):

Drinking Water ◽

Microbial Community ◽

Water Temperature ◽

Water Reservoir ◽

Field Research ◽

Pollutant Removal ◽

Chl A ◽

Drinking Water Reservoir ◽

Aeration System ◽

Significant Difference

Field research on the performance of pollutant removal and the structure of the microbial community was carried out on a drinking water reservoir. After one month of operation of a water-lifting aeration system, the water temperature difference between the bottom and the surface decreased from 9.9 to 3.1 °C, and the concentration of the dissolved oxygen (DO) in the bottom layer increased from 0 to 4.2 mg/L. The existing stratification in the reservoir was successfully eliminated. Total nitrogen (TN), total phosphorus (TP), and total organic carbon (TOC) concentrations were reduced by 47.8%, 66.7%, and 22.9%, respectively. High-throughput sequencing showed that Proteobacteria, Bacteroides, and Actinomycetes accounted for 67.52% to 78.74% of the total bacterial population. Differences in the bacterial changes were observed between the enhanced area and the control area. With the operation of the water-lifting aeration system, the populations of bacteria of the main genera varied temporally and spatially. Principal component analysis pointed out a clear evolution in the vertical distribution of the microbial structure controlled by the operation of the aeration system. Permutational analysis of variance showed a significant difference in the microbial community (p < 0.01). Redundancy analysis showed that physical (water temperature, DO) and chemical environmental factors (Chl-a, TOC, TN) were the key factors affecting the changes in the microbial communities in the reservoir water. In addition, a hierarchical partitioning analysis indicated that T, Chl-a, ORP, TOC, pH, and DO accounted for 24.1%, 8.7%, 6.7%, 6.2%, 5.8%, and 5.1% of such changes, respectively. These results are consistent with the ABT (aggregated boosted tree) analysis for the variations in the functional bacterial community, and provide a theoretical basis for the development and application of biotechnology.

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WATER QUALITY MANAGEMENT IN A DRINKING WATER RESERVOIR

Lake and Reservoir Management ◽

10.1080/07438148609354658 ◽

1986 ◽

Vol 2 (1) ◽

pp. 363-371 ◽

Cited By ~ 6

Author(s):

G. Dennis Cooke ◽

Robert E. Carlson

Keyword(s):

Water Quality ◽

Drinking Water ◽

Quality Management ◽

Water Quality Management ◽

Water Reservoir ◽

Drinking Water Reservoir

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Temporal variability in water quality parameters—a case study of drinking water reservoir in Florida, USA

Environmental Monitoring and Assessment ◽

10.1007/s10661-012-2870-z ◽

2012 ◽

Vol 185 (5) ◽

pp. 4305-4320 ◽

Cited By ~ 10

Author(s):

Gurpal S. Toor ◽

Lu Han ◽

Craig D. Stanley

Keyword(s):

Water Quality ◽

Drinking Water ◽

Temporal Variability ◽

Water Reservoir ◽

Quality Parameters ◽

Water Quality Parameters ◽

Drinking Water Reservoir

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Prioritizing riparian corridors for ecosystem restoration in urbanizing watersheds

PeerJ ◽

10.7717/peerj.8174 ◽

2020 ◽

Vol 8 ◽

pp. e8174 ◽

Cited By ~ 1

Author(s):

Samuel F. Atkinson ◽

Matthew C. Lake

Keyword(s):

Water Quality ◽

Drinking Water ◽

Ecosystem Services ◽

Watershed Management ◽

Water Reservoir ◽

Riparian Restoration ◽

Surface Slope ◽

Management Options ◽

Riparian Corridors ◽

Drinking Water Reservoir

Background Riparian corridors can affect nutrient, organic matter, and sediment transport, all of which shape water quality in streams and connected downstream waters. When functioning riparian corridors remain intact, they provide highly valued water quality ecosystem services. However, in rapidly urbanizing watersheds, riparian corridors are susceptible to development modifications that adversely affect those ecosystem services. Protecting high quality riparian corridors or restoring low quality corridors are widely advocated as watershed level water quality management options for protecting those ecosystem services. The two approaches, protection or restoration, should be viewed as complementary by watershed managers and provide a foundation for targeting highly functioning riparian corridors for protection or for identifying poorly functioning corridors for restoration. Ascertaining which strategy to use is often motivated by a specific ecosystem service, for example water quality, upon which watershed management is focused. We have previously reported on a spatially explicit model that focused on identifying riparian corridors that have specific characteristics that make them well suited for purposes of preservation and protection focused on water quality. Here we hypothesize that focusing on restoration, rather than protection, can be the basis for developing a watershed level strategy for improving water quality in urbanizing watersheds. Methods The model described here represents a geographic information system (GIS) based approach that utilizes riparian characteristics extracted from 40-meter wide corridors centered on streams and rivers. The model focuses on drinking water reservoir watersheds that can be analyzed at the sub-watershed level. Sub-watershed riparian data (vegetation, soil erodibility and surface slope) are scaled and weighted based on watershed management theories for water quality, and riparian restoration scores are assigned. Those scores are used to rank order riparian zones –the lower the score the higher the priority for riparian restoration. Results The model was applied to 90 sub-watersheds in the watershed of an important drinking water reservoir in north central Texas, USA. Results from this study area suggest that corridor scores were found to be most correlated to the amount of: forested vegetation, residential land use, soils in the highest erodibility class, and highest surface slope (r2 = 0.92, p < 0.0001). Scores allow watershed managers to rapidly focus on riparian corridors most in need of restoration. A beneficial feature of the model is that it also allows investigation of multiple scenarios of restoration strategies (e.g., revegetation, soil stabilization, flood plain leveling), giving watershed managers a tool to compare and contrast watershed level management plans.

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Occurrence of cyanobacteria, actinomycetes, and geosmin in drinking water reservoir in Korea: a case study from an algal bloom in 2012

Water Science & Technology Water Supply ◽

10.2166/ws.2020.102 ◽

2020 ◽

Vol 20 (5) ◽

pp. 1862-1870

Author(s):

Jung Eun Lee ◽

Seok-Jae Youn ◽

Myeongseop Byeon ◽

Soon-Ju Yu

Keyword(s):

Water Quality ◽

Drinking Water ◽

Cell Density ◽

Algal Bloom ◽

Water Reservoir ◽

Primary Source ◽

High Concentration ◽

Drinking Water Reservoir ◽

Peak Value

Abstract In 2012, a large concentration of geosmin was found in the Paldang reservoir, which is the primary source of drinking water in Seoul, Korea. In June and September 2012, we measured the concentrations of cyanobacteria and actinomycetes, and geosmin, to identify the source of geosmin in the Paldang reservoir. A total of 68 water samples were collected from two sampling sites (Sambong, Paldang), and used to analyze the correlation between cyanobacteria, actinomycetes, and geosmin. The cell density attained a maximum of 24,722 cells/mL on August 11, 2012 and geosmin occurred at a high concentration of 3,934 ng/L on August 13 in Sambong. After July 31, 2012 a rapid increase in growth and cell density occurred with a peak value of 11,568 cells/mL on August 6, 2012. At the same time, the geosmin concentration increased to 3,157 ng/L in Paldang. The number of cyanobacteria positively correlated with geosmin concentration (R2 = 0.84, P < 0.0001), while actinomycetes were not significantly correlated with geosmin (R2 = 0.01, P = 0.709). In addition, the number of actinomycetes was associated with increased turbidity (R = 0.507). Among the various water quality constituents, temperature affected cyanobacteria in the Paldang reservoir (R = 0.803). These results suggest that cyanobacteria are the main source of geosmin in the Paldang reservoir, which might be providing useful information for managing the unpleasant taste of its drinking water.

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