Probabilistic Model of Ammonia and Toxicity Status for Urban Lake

Gelda, Rakesh K.; Effler, Steven W.; O’Donnell, Susan M.

doi:10.1061/(asce)0733-9496(2001)127:5(337)

Cited by 23 publications

(26 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1c) is supported by recent sediment deposition studies conducted with sediment traps (deposition was ∼4-fold greater at site 3 than at site 1 in 2003; Effler et al 2007b). This approach (Owens et al 1998a;Gelda et al 2001) has the advantages of incorporating the effects of wider variations in meteorological and operational forcing conditions contained in this period that are inherently representative for this system, and supporting presentations of projections in probabilistic formats that are more consistent with reality and regulatory limits (Owens et al 1998a). The respecification for 2067 scenarios assumes the same magnitude and spatial pattern of deposition in the future as observed over the period of operation of the reservoir (Fig.…”

Section: Development Of Scenariosmentioning

confidence: 62%

Testing and application of a two-dimensional hydrothermal model for a water supply reservoir: implications of sedimentation

Gelda¹,

Effler²

2007

Journal of Environmental Engineering and Science

View full text Add to dashboard Cite

Validation of a two-dimensional hydrothermal stratification model for 14 years for Schoharie Reservoir, N.Y., an impoundment that experiences substantial drawdown, is documented. The model is demonstrated to perform well in simulating the various features of the reservoir's thermal stratification regime in each of the years, including the timing and duration of stratification, the dimensions and temperature of the layers, and the periods of internal wave oscillations in stratified layers. The average root mean square error for temperature predictions for the 14 years is 1.30 • C. The validated model is applied in a probabilistic manner to investigate the impacts of sedimentation on the temperature of the withdrawn water (T w ) that enters a stream with a salmonid fishery, and features of the stratification regime. The predicted effects of sedimentation include a shift toward higher T w values, a shortening of the duration of stratification, and decrease in the depth of the epilimnion in fall. The effects on T w are exacerbated for the reservoir because of localized sedimentation adjoining the intake that increasingly limits access to cooler layers.Résumé : Cet article documente la validation d'un modèle de stratification hydrothermique bidimensionnel sur 14 années au réservoir Schoharie, NY, une retenue qui connaît des rabattements substantiels. Il est démontré que le modèle travaille bien lors de simulations des diverses caractéristiques du régime de stratification thermique du réservoir pour chacune des années, incluant le moment et la durée de la stratification, les dimensions et la température des couches ainsi que les périodes d'oscillations des vagues internes dans les couches stratifiées. L'erreur quadratique moyenne pour les prévisions de température pour les 14 années est de 1,30 • C. Le modèle validé est appliqué de manière probabiliste afin d'étudier les impacts de la sédimentation sur la température de l'eau soutirée (T w ), qui entre dans un ruisseau comportant une pêcherie de salmonidés; le modèle étudie aussi les caractéristiques du régime de stratification. Les effets prévus de la sédimentation comprennent un déplacement vers des valeurs T w plus élevées, un raccourcissement de la durée de stratification et une diminution de la profondeur de l'épilimnion à l'automne. Les effets sur les valeurs T w sont exacerbés pour le réservoir en raison d'une sédimentation localisée près de la prise d'eau en réservoir, ce qui limite de plus en plus l'accès aux couches plus froides.

show abstract

Section: Development Of Scenariosmentioning

confidence: 62%

Testing and application of a two-dimensional hydrothermal model for a water supply reservoir: implications of sedimentation

Gelda¹,

Effler²

2007

Journal of Environmental Engineering and Science

View full text Add to dashboard Cite

show abstract

“…Based on the assumption that historical weather and hydrologic conditions are representative of future conditions, the observed conditions for the spring to fall period of 22 years (1989 through 2010) were used as model inputs, to provide a probabilistic context for the simulations [30,31] that represents the effects of year-to-year variations in meteorology and hydrology. The potential for discharging all of the treated and bypass flow, or a portion of this flow, through an offshore outfall is also evaluated using the history of wastewater flow reaching the plant for the same 22 years.…”

Section: E M Owens Et Almentioning

confidence: 99%

Evaluation of Offshore Wastewater Outfall and Diffuser for Onondaga Lake, NY

Owens¹,

Effler²,

Matthews³

et al. 2013

JWARP

Self Cite

View full text Add to dashboard Cite

Outfall alternatives are evaluated for a municipal wastewater treatment facility that discharges effluent at the shoreline of an urban lake. Occurrence of plumes of poorly diluted effluent in adjoining portions of the lake is described. Alternatives considered include outfalls over a range of depth and various diffuser designs. Benefits and impacts on lake stratification and dissolved oxygen are evaluated for an array of design alternatives with a model which links a far field hydrothermal and transport submodel with a near field buoyant plume submodel. Outfall design features are described that: 1) reduce shoreline discharge of bypass flow of partially treated wastewater during major runoff events; 2) eliminate plumes of poorly diluted effluent; and 3) reduce loading of the effluent to the upper waters. A deep (10 to 14 m) outfall with a multiport diffuser would reduce the loading of the facility's effluent to the upper waters by approximately 40%, without noteworthy impact on stratification or dissolved oxygen.

show abstract

“…The strategy for development of the probabilistic framework has broad utility for different constituents and ecosystems, including within the context of Total Maximum Daily Load analyses (Gelda et al 2001). Shorter records of drivers than adopted here will likely be adequate to represent variability in many other systems where operations are not as important a factor as for the study reservoir.…”

Section: Management Implicationsmentioning

confidence: 99%

“…Long-term records of environmental forcing conditions, such as meteorology and operations of reservoirs, offer opportunities to represent the effects of variations in these important drivers in model forecasting (Owens and Effler 1989, Gelda et al 2001. Using long-term data sets as model inputs eliminates Downloaded by [Northeastern University] at 13:56 20 November 2014 the arbitrariness of a priori specification of critical conditions in complex situations (such as for reservoirs) because inputs described by these measurements actually occurred and are inherently representative , Gelda et al 2001. Moreover, the predictive capability of a successfully tested model represents the effects of variability in these forcing conditions.…”

mentioning

confidence: 99%

“…Moreover, the predictive capability of a successfully tested model represents the effects of variability in these forcing conditions. Presentation of such long-term simulations in a probabilistic (e.g., cumulative percent occurrence) format (Gelda et al 2001) provides a valuable perspective on reasonable variability in expected water quality, which can lead to an objective identification of critical forcing conditions (Gelda and Effler 2003). Longer monitoring records are expected to more completely represent variability.…”

mentioning

confidence: 99%

See 1 more Smart Citation