Prevent Seawater Intrusion Research Articles

Fate of Polybrominated Diphenyl Ethers, Nonylphenol, and Estrogenic Activity during Managed Infiltration of Wastewater Effluent

About a billion cubic meters of wastewater effluent are artificially recharged annually in the United States for maintenance of groundwater levels and prevention of seawater intrusion. There is concern that trace contaminants, including various endocrine disrupting compounds (EDCs), are not completely removed during infiltration, leading to deterioration of groundwater quality. In this work, we investigate the mechanisms and efficiency of EDC removal at the Sweetwater Recharge Facility, which is used to recharge secondary effluent from the Roger Road Wastewater Treatment Plant in Tucson, Ariz. Material was collected from the top meter of sediments in two infiltration basins and analyzed for extractable nonylphenol (NP), polybrominated diphenyl ethers (PBDE) and total estrogenic activity. The basins differed significantly in length of service (7 versus 15 years). Nevertheless, profiles of extractable contaminants and estrogenic activity were similar in the two basins. Results suggest that hydrophobic deter...

Optimal schemes of groundwater exploitation for prevention of seawater intrusion in the Leizhou Peninsula in southern China

The Lei-Qiong Depression Zone, near the Leizhou Peninsula in southern China, consists of unconsolidated sediments of 500–3,000 m thickness. Groundwater occurs in a multi-aquifer system in the Leizhou Peninsula. The aquifers receive recharge from precipitation, canal and reservoir infiltration, and discharge mainly through subterranean drainage into the sea. Artificial pumping for drinking and agricultural purposes is another way of groundwater discharge. Groundwater development along the coast faces the threat of seawater intrusion. A quasi-three-dimensional finite element model, containing 457 nodes and 833 elements, has been used to simulate the spatial and temporal distribution of groundwater levels in the three-aquifer system. Verification of various aquifer parameters and boundary conditions was performed with the simulation model. Linear programming models have been developed for groundwater exploitation within the two confined aquifers. The objective function of the models is to maximize the total groundwater pumpage from the confined aquifers. Control of seawater intrusion is examined by restricting the water levels at points along the coast and the withdrawal rates in coastal management cells. A response matrix approach was used in the optimization models. The response matrix was obtained from the simulation model by forecasting drawdown produced by pumping at a unit impulse discharge. Groundwater development in the Leizhou Peninsula can be primarily optimized by allocating the pumping rates of the management cells.

Remediation of Sea Water Intrusion: A Case Study

AbstractSea water intrusion and remediation in the Upper Floridan Aquifer in South Carolina is simulated using the finite‐element model SUTRA developed by the U.S. Geological Survey. A sensitivity analysis of the effect of the hydrogeologic parameters on the sea water recharge and seepage velocities is performed. An increase in confining unit and/or in aquifer conductivity results in an increase of the sea water recharge. An increase in aquifer porosity results in a decrease of the sea water recharge. Among the three remedial techniques simulated—reduced aquifer withdrawals, an injection well, and a combined injection and capture well—the reduced aquifer withdrawals and injection well are the best methods for preventing sea water intrusion.

A 120 year record of changes in nitrogen and carbon cycling in Lake Alexandrina, South Australia: C:N, δ15N and δ13C in sediments

Variations in δ 15N and δ 13C and C:N ratios of organic matter in sediment cores in Lake Alexandrina, South Australia show that there have been modifications of N and C sources due to land use changes, water diversions and irrigation since European settlement of the surrounding basin in the middle 1800s. δ 15N org and δ 13C org concentrations from three short sediment cores range from 1.8 to 3.9‰ and −26.7 to −21.1‰, respectively. All cores showed a ∼2‰ increase in δ 15N over the top 100 mm with little variation below about 150 mm. δ 13C values increased by about ∼3‰ from the base of the sediment cores to a maximum of ∼−21‰ at 150 mm depth, before decreasing by ∼5‰ to ∼–27‰ over the top 100 mm. C:N mass ratios <11 suggest that organic matter preserved in the sediment is composed primarily of aquatic plant material, with terrestrial plants contributing <10%. Excess 210Pb and 137Cs dating indicate a sediment accumulation rate of 3±1 mm a −1 suggesting the enrichment in 15N began in the 1950s and the δ 13C maxima corresponds to approximately 1940. The increase in δ 15N concentration over the past 30–50 a is attributed to the increasing agricultural expansion and development in the lower catchment, particularly intensive grazing of cattle for dairying. The authors suggest that there has been an increased flux of 15N-enriched inorganic N (derived from mineralized animal waste and sewage) to the river and lake over the past 30–40 a, which in turn is incorporated into the aquatic plants. The variation in δ 13C reflects a change from terrestrial dominated input of inorganic C to increasingly marine dominated sources after water diversions commenced in the late 1800s. Once barrages were completed at the outlet of the lake in 1939 (to prevent seawater intrusion), the aquatic plants in the lake reverted to assimilation of dissolved inorganic C derived from oxidation of terrestrial organic matter.

Managing urban wastewater for maximising water resource utilization

The Atlantis Water Resource Management Scheme uses artificial recharge of urban stormwater and treated wastewater to augment the natural groundwater resource. The key to the success of the scheme is the fractionation of the stormwater into components of distinctly different quality, and the separate treatment of domestic and industrial wastewater for different end-uses. The groundwater exploitation strategy is largely controlled by water quality requirements. Reuse of domestic and industrial wastewater depends on quality parameters. Tertiary treated domestic effluent is destined for indirect reuse via the aquifer, while treated industrial wastewater is used together with spent regenerant brine and stormwater from the noxious trade area for preventing seawater intrusion. Both residential and industrial stormwater is separated into the base flow and storm flow components and utilised for various purposes. The sustainable operation of the water resource scheme serves as a prototype for the optimal use of water and protection of the environment.

Managing urban wastewater for maximising water resource utilization

The Atlantis Water Resource Management Scheme uses artificial recharge of urban stormwater and treated wastewater to augment the natural groundwater resource. The key to the success of the scheme is the fractionation of the stormwater into components of distinctly different quality, and the separate treatment of domestic and industrial wastewater for different end-uses. The groundwater exploitation strategy is largely controlled by water quality requirements. Reuse of domestic and industrial wastewater depends on quality parameters. Tertiary treated domestic effluent is destined for indirect reuse via the aquifer, while treated industrial wastewater is used together with spent regenerant brine and stormwater from the noxious trade area for preventing seawater intrusion. Both residential and industrial stormwater is separated into the base flow and storm flow components and utilised for various purposes. The sustainable operation of the water resource scheme serves as a prototype for the optimal use of water and protection of the environment.

The Feasibility Study for Development of Groundwater Resources by Subsurface Dam for Prevention of Salt Water Intrusion

Groundwater development in small islands often requires management to prevent sea water intrusion into coastal aquifers. In this paper, therefore, a two-dimensional fresh and salt water flow model is studied to increase irrigation water supply to a sugar cane field. Both the groundwater flow rate across the area of a planned subsurface dam and the movement of immiscible fresh-salt water interface are predicted by the present model. A preliminary evaluation for a feasible groundwater development is attempted. The groundwater flow rate across the dam site to the sea is predicted as about 329×103 m3/year for the precipitation 1267mm in 1991, which is 73% of the average annual precipitation of 1734mm.

Orange county's 5 MGD reverse osmosis plant

The Orange County Water District has constructed a 5 million gallon per day reverse osmosis treatment facility, the largest in the world today operating on municipal wastewater. This unit is part of the District's advanced wastewater treatment plant known as Water Factory 21, where municipal wastewater is treated and injected through injection wells. This provides a hydraulic barrier for prevention of seawater intrusion into underground aquifers.Due to excessive withdrawals of groundwater in the early 1920's, seawater advanced into the District's underground fresh water aquifers and threatened the entire basin. Extensive recharge facilities have been constructed in the forebay area, but after lengthy evaluation it was determined that further facilities were needed along the coast to block seawater intrusion. The reverse osmosis unit, constructed in 1976-77, is now operating, and performance data is available. The District has shown that plant specifications can be formulated which will require removal efficiencies along with specified energy and chemical consumption.

Development of a Fresh‐Water Barrier in Southern California for the Prevention of Sea Water Intrusion

in the world where the overdevelopment of coastal ground water supplies has upset nature's balance, reversing normal fresh water gradients and permitting sea water to degrade the fresh water. Such intrusion will eventually destroy the usefulness of the entire ground water reserves of the affected basin unless preventive measures are undertaken. Through personal contact and correspondence with engineering personnel from various coastal states in the United States and from

Experiments With Fresh‐Water Barrier to Prevent Sea Water Intrusion

Journal AWWAVolume 45, Issue 5 p. 521-534 Article Experiments With Fresh-Water Barrier to Prevent Sea Water Intrusion Paul Baumann, Paul BaumannSearch for more papers by this author Paul Baumann, Paul BaumannSearch for more papers by this author First published: 01 May 1953 https://doi.org/10.1002/j.1551-8833.1953.tb20138.xCitations: 5AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume45, Issue5May 1953Pages 521-534 RelatedInformation