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CE4505 Surface Water Quality Engineering. Modeling Lecture 1. Modeling and Sustainability. CE4505 – Surface Water Quality Engineering. Sustainability. In our every deliberation we must consider the impact of our decisions on the next seven generations. Iroquois Confederacy.
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CE4505 Surface Water Quality Engineering Modeling Lecture 1. Modeling and Sustainability CE4505 – Surface Water Quality Engineering
Sustainability In our every deliberation we must consider the impact of our decisions on the next seven generations. Iroquois Confederacy Meeting the needs of the present without compromising the ability of future generations to meet their own needs. World Commission on Environment and Development, 1987 http://www.interspecies.com/pages/7th_gen.html http://www.bathtram.org/tfb/tE04.htm CE4505 – Surface Water Quality Engineering
Modeling …a mathematical model is an idealized formulation that represents the response of a physical system to external stimuli. CE4505 – Surface Water Quality Engineering Chapra 1997, p. 10
Toward Sustainability Decisions supporting a sustainable future require: 1) a knowledge of the way a system works. We might think of this as a research model. 2) a manner of predicting cause and effect. We might think of this as a management model. CE4505 – Surface Water Quality Engineering
Understanding the System The Blind Men and the Elephant John Godfrey Saxe, 1816-1887 CE4505 – Surface Water Quality Engineering http://www.wordinfo.info/words/index/info/view_unit/1/?letter=B&spage=3
To Better See the Elephant … The Third approached the animal, And happening to take The squirming trunk within his hands, Thus boldly up and spake: “I see,” quoth he, “the Elephant Is very like a snake!” And so these men of Indostan Disputed loud and long, Each in his own opinion Exceeding stiff and strong, Though each was partly in the right, And all were in the wrong! The Sixth no sooner had begun About the beast to grope, Than, seizing on the swinging tail That fell within his scope, “I see,” quoth he, “the Elephant Is very like a rope!” So oft in theologic wars, The disputants, I ween, Rail on in utter ignorance Of what each other mean, And prate about an Elephant Not one of them has seen! The Fourth reached out an eager hand, And felt about the knee. “What most this wondrous beast is like Is mighty plain,” quoth he; “ ‘Tis clear enough the Elephant Is very like a tree!” It was six men of Indostan To learning much inclined, Who went to see the Elephant (Though all of them were blind), That each by observation Might satisfy his mind The Fifth, who chanced to touch the ear, Said: “E’en the blindest man Can tell what this resembles most; Deny the fact who can This marvel of an Elephant Is very like a fan!” The First approached the Elephant, And happening to fall Against his broad and sturdy side, At once began to bawl: “God bless me! but the Elephant Is very like a wall!” The Second, feeling of the tusk, Cried, “Ho! what have we here So very round and smooth and sharp? To me ’tis mighty clear This wonder of an Elephant Is very like a spear!” CE4505 – Surface Water Quality Engineering
Research Models To provide a better understanding of the mechanisms and interactions that give rise to various types of water quality behavior, such understanding to be sharpened by the formulation and testing of hypotheses of the cause-effect relationships between residual inputs and resulting water quality. (Thomann and Mueller 1987) CE4505 – Surface Water Quality Engineering
To Validate our Understanding of System Response Mathematical Model Process Studies Field Observations Conceptual Framework Why model? The research perspective – CE4505 – Surface Water Quality Engineering
Predicting Cause and Effect CE4505 – Surface Water Quality Engineering
Cause & Effect: firing a projectile by Trial and Error CE4505 – Surface Water Quality Engineering
Cause and Effect: achieving sustainability by Build and Measure CE4505 – Surface Water Quality Engineering
Undesirable Outcomes underdesign - …the environmental engineering equivalent of building a bridge that falls down. www.civil.columbia.edu/ce4210/bridgecollapse.html (Thomann and Mueller 1987, p. ix) CE4505 – Surface Water Quality Engineering
Undesirable Outcomes overdesign - …the environmental engineering equivalent of building a bridge to nowhere. http://www.zen39641.zen.co.uk/ps/ (Thomann and Mueller 1987, p. ix) CE4505 – Surface Water Quality Engineering
distance angle Cause and Effect: firing a projectile by Applying a Model CE4505 – Surface Water Quality Engineering
Cause and Effect: achieving sustainability Linking … Action and Reaction Perturbation and Response Cause and Effect by Applying a Model CE4505 – Surface Water Quality Engineering
A Water Quality Management Plan • Specify water use • Establish water quality criteria • Determine cause and effect • Identified engineered alternatives • Conduct cost-benefit analysis • Evaluate socioeconomic impact CE4505 – Surface Water Quality Engineering
Why Model? To provide a more rational basis for making water quality control decisions, such a basis to include a defensible, credible, predictive framework, within the larger framework of cost-benefit analysis. (Thomann and Mueller 1987) CE4505 – Surface Water Quality Engineering
Why model? Guidance for Management Actions Mathematical Model Quantification of Loads Characterization of Fate & Transport Engineered Solutions CE4505 – Surface Water Quality Engineering
Model Implementations Define “a” as an assimilation factor, L3·T-1 Simulation Mode Design Mode 1 – assimilative capacity Design Mode 2 – environmental modification CE4505 – Surface Water Quality Engineering
Water and Wastewater in an Urban Setting (Chapra 1997, Figure 1.1) CE4505 – Surface Water Quality Engineering
The Water Quality Management Process (Chapra 1997, Figure 1.2) CE4505 – Surface Water Quality Engineering
Opportunities • universities/institutes (UFI) • government (LLRS) • consulting (LTI) Upstate Freshwater Institute Syracuse, New York Limno Tech, Inc. Ann Arbor, Michigan EPA Large Lakes Research Station Grosse Ile, Michigan CE5504 – Surface Water Quality Modeling