FLOOD11151 - Laserfiche WebLink

Home Browse Search

- 4 - . A suggestion to revise the original WRDA Bill language was made by Aurora. The CWCB supports the suggested revision, and there does not seem to be any opposition from the water users. The suggested revision is included below. Denver has agreed to work with their congressional delegation to get the revision into the Bill this fall. Water Users are encouraged to review the language and let the group know ASAP if there are any issues. "Any release of water for environmental restoration--aAfi or enhancement shall be in accordance with the operating principles for instream flow as agreed upon by the Downstream Cooperative Group participating in the e.xfsfjng Chatfield Reservoir Storage Reallocation Feasibility Study" Other Downstream Group Activities - Marc Waage Example of Winter Flow Restoration. . Passed around graphs showing low winter outflow from Chatfield and an example of how the DS Coop could use 4200AF of reallocated space in Chatfield to boost the winter flows. . Graphs were based on PACSM model of 1947 to 1992 hydrology. . Water availability was from the "Chatfree" file for junior water rights. Storage would occur in the spring and releases made in winter to boost low flows. Downstream users would redivert the winter releases at Brighton or below. Up to 100 cfs diversion capability is expected. . 4200 afbased on the 45%/55% winter/summer split in the DS Coop MOD. . Model run based on current demand levels and included operation ofthe Kassler pump station. Prior to the pump station the fish flow releases would typically "spill" from Chatfield in the winter. . Doesn't include Brighton's senior water rights. . Example is preliminary because it was not reviewed by the downstream users. Revised Outflow Release . Handed out draft of revised Chatfield release pattern for the DS Coop for use in EIS. . The release pattern submitted in Dec 2004 included some river flow restoration (55% summer/45% winter split for instream flow goals per DS MOU was used). . Corps proposed restoration study makes it uncertain if Corps will waive reimburse costs to allow for a flow restoration program. So, pattern is being adjusted for operations without any restoration flows. Water would simply be released on demand of downstream users instead of releasing to meet the instream flow goals. . To finish, need Western Mutual Ditch releases and need to put into daily model. Streamflow Restoration Study. . Discussed conference call between Corps, Tetra Tech, and DW to compare difference between the EIS and the environmental restoration study on the impacts to the river below Chatfield. DS Coop believes much of the EIS work can be the basis for restoration study. Corps says restoration study needs to be more detailed than an EIS. Tetra Tech says EIS analysis will be mostly qualitative. Corps wants quantitative analysis for restoration study. . Discussion about how much would be required for Corps to waive reimbursement costs. . Plan is to gather available data on river, involve someone from Corps headquarters, and convene "expert group" to further define how much study will be needed. . Corps wants EP A, FWS, and DOW on expert panel. Corps' question for panel - is there enough federal interest in restoring the South Platte for the restoration study to proceed? . Terry Baus can help convene experts from previous work on metro river reach. . Marc Waage can help with available data - need Corps to define what looking for. . DS Coop does not want the restoration study to slow down the EIS. Flood Protection . Water Project Planning and Finance. Stream and Lake Protection Water Supply Protection. Conservation Planning