Please use this identifier to cite or link to this item:
Title: G-3273 Constraint Relaxation/S-356 Field Test and S-357N Revised Operational Strategy: Increment 1 plus (Increment 1.1 and 1.2) : Appendix C, Monitoring Plan
Authors: United States. Army. Corps of Engineers. Jacksonville District.
Keywords: Flood control
Environmental protection
Everglades (Fla.)
Publisher: United States. Army. Corps of Engineers. Jacksonville District.
Abstract: The original water quality and hydrology monitoring plan presented here for the proposed G-3273 Constraint Relaxation/S-356 Field Test and S-357N Operational Study was developed by an interagency team from SFWMD, USACE, DOI, and FDEP. This revised monitoring plan, which supports continuation of the previous Increment 1 field test (documented in the May 2015 Environmental Assessment (EA); hereafter referred to as Increment 1) and updates in response to new information, is hereafter referred to as Increment 1.1/1.2. The proposed water quality monitoring plan will provide data to: (1) assess achievement of phosphorus target for S-356 discharges; (2) distinguish water sources for S-35; (3) quantify water quality interactions associated with the test through detailed analysis of chemical and physical parameters; and (4) characterize the S-328 discharges. Source attribution and characterization are needed to guide water quality management efforts in the future. The proposed monitoring plans for surface water hydrology and groundwater hydrology will provide data to: (1) assess the zone of influence of the S-356 pump station under a range of pumping scenarios; (2) develop water budgets of the L-31N Canal (north and south of the S-331 pump station) and the C-111 Canal (between S-176 and S-177) under representative operational scenarios; (3) assess performance of the 8.5 SMA project components, including S-357 and S-357N (pending construction completion), to maintain the surface water and groundwater levels within the project areas of the 8.5 SMA, between the L-357W Levee and the L-31N Levee at the same levels as existed prior to the implementation of any MWD Project components; (4) demonstrate S-356's ability to manage additional seepage caused by increased MWD flows into NESRS under a range of hydrologic conditions; (5) quantify the net effects within the L-31N Basin (south of S-331 and north of S-176) and the C-111 Basin (south of S-176) from the of reduced WCA 3A regulatory discharges to NESRS combined with increased flood control releases from S-331/S-173 and increased seepage to the L-31N Canal south of S-331, including the capability of the S-332B/C/D pump stations and the C-111 South Detention Area to manage potential additional flows into the L-31N Canal under certain operational conditions; and (6) incorporate the ongoing SFWMD operations, monitoring, and performance assessments conducted as part of the CERP C-111 Spreader Canal Western Project. Items (5) and (6) are addressed within Annex 1 of the monitoring plan. In developing the original Increment 1 monitoring plan (Appendix C of the May 2015 EA), the interagency teams reviewed the ongoing monitoring efforts within the study area as of October 2014 to determine what existing and additional monitoring would likely be required to fully evaluate the hydrologic and water quality impacts associated with relaxing the G-3273 operations constraint during Increment 1.1/1.2 testing. Additional monitoring requirements have since been incorporated into the Increment 1 monitoring plan based on the operational strategy for Increment 1.1/1.2, which included consideration of new information as described in the Supplemental EA. The Increment 1 testing was originally expected to last up to two years. The combined duration of Increment 1 and Increment 1.1/1.2 may extend beyond the two calendar years initially envisioned for Increment 1 to compensate for the temporary suspension of the Increment 1 field test during the 2016 L-29 Canal temporary emergency deviation and extended recovery period (February-November 2016). In addition to the emergency deviation, extension of the Increment 1 and Increment 1.1/1.2 field test duration to up to three years will allow sufficient time to complete the C-111 South Dade construction components needed to operate the NDA during Increment 2 of the MWD Project. Updated sampling frequencies have also been incorporated into this revised monitoring plan, based on consideration of the extended duration of the field test and a new groundwater monitoring contract planned for August 2017. Increment 1.1/1.2 will extend until implementation of Increment 2. At the completion of Increment 1.1/1.2 testing, a portion of the additional monitoring proposed in this plan may be carried forward to Increment 2 testing or other operating conditions that may follow. New monitoring stations are preliminarily identified in this plan. As such, this plan incorporates the best information available; however, as the test operations are implemented, this plan may require revision. Late in the development of this original Increment 1 plan, the formulation efforts recommended consideration of a change to the operational criteria of the S-197 structure. This change precipitated the need to amend the water quality and hydrology monitoring plan to incorporate additional monitoring south of the S-331 structure. Rather than re-write the monitoring plan, the additional monitoring required due to changed operations at S-197 are detailed in “Annex 1, Increment 1 Monitoring South of S-331” of this plan. This revised annex is attached to the main body of the monitoring plan. While the near record-high WCA-3A stages during February-March 2016 created many water management challenges, the 2016 temporary emergency deviation executed in response to these conditions provided valuable information on the responses within ENP and the SDCS system to raising of the L-29 Canal, including evaluation of operational limitations of the 8.5 Square Mile Area flood mitigation project prior to completion of the MWD and C-111 South Dade projects. Based on information gained during operation during the 2016 Emergency Deviation and the subsequent expanded recovery period, in addition to the inclusion of additional operational flexibility within the Operational Strategy for Increment 1.2 allowing operation of the L-29 Canal to a maximum operating limit of 7.8 feet NGVD, an expanded hydrologic monitoring plan for the 8.5 SMA is needed to complement the revised objectives of the Increment 1.1/1.2 Operational Strategy. The supplemental monitoring requirements for the 8.5 SMA are detailed in “Annex 2, Increment 1 Monitoring for 8.5 SMA Flood Mitigation.”
Appears in Collections:Environmental Documents

Files in This Item:
File Description SizeFormat 
Appendix C Monitoring Plan Inc 1 Plus For Print.pdf4.75 MBAdobe PDFThumbnail