48
Webb Van Winkle and John Kadvany
Sidebar 3.1
More complex and realistic was not more effective
In the mid-1960s, concerns surfaced regarding entrainment and
impingement of young-of-the-year (age-0) striped bass by electricpower-generating facilities on the Hudson River. These concerns
stimulated the development of increasingly complex models to
evaluate the impacts of these facilities. Christensen and Englert
(1988) reviewed the history and compared the 11 models that were
developed over a 15-year period [also see Barnthouse et al. (1984);
Barnthouse et al. (1988); Barnthouse (2000); Swartzman et al. (1977)].
The earliest simplistic formulas, based on empirical data, proved
inadequate because of conceptual shortcomings, incomplete development, and lack of data. By 1972, complex transport models based on
biological and hydrodynamic principles had been developed and
applied by scientists representing both the utilities and the government. Disagreements about the acceptability of these models spurred
the development of even more complex models. The entrainment
models stimulated the collection of substantial amounts of field data
to define the spatial distributions and entrainment survival of early
life stages. As the difficulties of accounting for the movement of early
life stages based on hydrodynamic principles became more evident
and as more field data became available, simpler empirical modeling
approaches became practical and defensible. Both empirical and
hydrodynamic modeling approaches were applied during the EPA’s
hearings on the Hudson River power case (1977 to 1980).
The main lessons learned from the experience with modeling of
entrainment and impingement are that complex, mechanistic models
are not necessarily better than simpler, empirical models for young
fish (Christensen and Englert 1988). The hearing process became
paralyzed by the complexity of the models and intractable scientific
issues relating to long-term predictions and density dependence.
However, the modeling activities clearly identified the need for
certain types of data, which stimulated the collection of such data,
albeit at considerable cost. As the field data became available, empirical modeling became increasingly attractive. While empirical models
required these data, they required a minimum number of assumptions, were easy to explain and defend, and could be inexpensively
run for different fish species and CWIS scenarios. They were particularly useful in the settlement egotiation process during 1979 and 1980.
Refinements of these empirical models continue to be tools that are
used in current repermitting activities of these Hudson River power
plants (D.J. Dunning, New York Power Authority, White Plains, New
York, personal communication, December 2000).
Webb Van Winkle and John Kadvany
Sidebar 3.1
More complex and realistic was not more effective
In the mid-1960s, concerns surfaced regarding entrainment and
impingement of young-of-the-year (age-0) striped bass by electricpower-generating facilities on the Hudson River. These concerns
stimulated the development of increasingly complex models to
evaluate the impacts of these facilities. Christensen and Englert
(1988) reviewed the history and compared the 11 models that were
developed over a 15-year period [also see Barnthouse et al. (1984);
Barnthouse et al. (1988); Barnthouse (2000); Swartzman et al. (1977)].
The earliest simplistic formulas, based on empirical data, proved
inadequate because of conceptual shortcomings, incomplete development, and lack of data. By 1972, complex transport models based on
biological and hydrodynamic principles had been developed and
applied by scientists representing both the utilities and the government. Disagreements about the acceptability of these models spurred
the development of even more complex models. The entrainment
models stimulated the collection of substantial amounts of field data
to define the spatial distributions and entrainment survival of early
life stages. As the difficulties of accounting for the movement of early
life stages based on hydrodynamic principles became more evident
and as more field data became available, simpler empirical modeling
approaches became practical and defensible. Both empirical and
hydrodynamic modeling approaches were applied during the EPA’s
hearings on the Hudson River power case (1977 to 1980).
The main lessons learned from the experience with modeling of
entrainment and impingement are that complex, mechanistic models
are not necessarily better than simpler, empirical models for young
fish (Christensen and Englert 1988). The hearing process became
paralyzed by the complexity of the models and intractable scientific
issues relating to long-term predictions and density dependence.
However, the modeling activities clearly identified the need for
certain types of data, which stimulated the collection of such data,
albeit at considerable cost. As the field data became available, empirical modeling became increasingly attractive. While empirical models
required these data, they required a minimum number of assumptions, were easy to explain and defend, and could be inexpensively
run for different fish species and CWIS scenarios. They were particularly useful in the settlement egotiation process during 1979 and 1980.
Refinements of these empirical models continue to be tools that are
used in current repermitting activities of these Hudson River power
plants (D.J. Dunning, New York Power Authority, White Plains, New
York, personal communication, December 2000).