Tetra Tech, Inc.

10306 Eaton Place, Suite 340 Fairfax, VA 22030 phone 703
- 385
- 6000 fax 703
- 385
- 6007

TO : Record FROM : Kelly

Meadows DATE: February 24 , 20
SUBJECT: Spawning seasons The attached documents present information on the species

. Attachment A (Spawning Season for Selected Fishes) illustrates the spawning period for a number of common fish species found in each waterbod y t ype. graphic, spawning occurs at all times of th to be present at any time of the year, depending on the waterbod y)

. Attachments B th r ough F were developed using site in New England and serve as illustrative example locations, the spawning season or all of the ye ar ; in some cases, flow reduction throughout the y ear (e.g., converting to closed

- cy cle cooling) may be the most peak s of these spawning period organisms would be present ; as a result, flow reductions that would achieve entrainment. Another factor to consider is what species are considered important; these graphics illustrate most of the species present choose to focus on selected species spawning periods, providing additional opportunities for flow reduction to be utilized. 

### MEMORANDUM

10306 Eaton Place, Suite 340

Kelly Meadows , 20 11 Spawning seasons present information on the spawning seasons of various
(Spawning Season for Selected Fishes) illustrates the spawning period for a number of common fish species found in each waterbod y t ype. As shown by

the graphic, spawning occurs at all times of th e y ear (i.e., “entrainable” organisms are likely to be present at any time of the year, depending on the waterbod y)

. were developed using site

- specific data at individual facilities and serve as illustrative example s . These plots show that, for some spawning season s for organisms present in the source water may span most ; in some cases, flow reduction throughout the y ear (e.g., converting to cy cle cooling) may

be the most app ropriate technology option . However, the of these spawning period s would be when the highest concentration of

; as a result, there may be opportunities for seasonal intake flow reductions that would achieve significant reductions in impingement and entrainment. Another factor to consider is what species are considered important; these graphics illustrate most of the species present at these sites , but resource managers may choose to focus on selected species of concern, which may narrow the scope of peak spawning periods, providing additional opportunities for flow reduction to be utilized.

1 spawning seasons of various aquatic
(Spawning Season for Selected Fishes) illustrates the spawning period for As shown by

the e y ear (i.e., “entrainable” organisms are likely

specific data at individual facilities . These plots show that, for some s for organisms present in the source water may span most ; in some cases, flow reduction throughout the y ear (e.g., converting to . However, the would be when the highest concentration of entrainable there may be opportunities for seasonal intake significant reductions in impingement and entrainment. Another factor to consider is what species are considered important; these , but resource managers may of concern, which may

narrow the scope of peak spawning periods, providing additional opportunities for flow reduction to be utilized.