Common use of Shark River Slough Total Phosphorus Concentration Compliance Tracking Clause in Contracts

Shark River Slough Total Phosphorus Concentration Compliance Tracking. The daily flows through the individual Shark River Slough structures and S334 from July 2001 through June 2003 are presented in Figure 4a. Since mid- November 2002 inflows to Shark River Slough have been through S333 and S12D. Beginning in mid-January 2003 a large proportion of the flow in the L29 Canal was released from the system through S334 due to above-average rainfall. This condition lasted until mid-June. The relationship between the sum of the daily flows at Shark River Slough structures and corresponding flow-weighted mean total phosphorus concentrations for individual sampling events is presented in Figure 4b. Values for Water Years 2001 and 2002 follow the strong inverse relationship between flow and total phosphorus concentration expected for waters entering the Park through Shark River Slough. However, during the un-seasonal rainfall conditions that occurred from February through June 2003, total phosphorus concentrations were greater and more variable, 9 to 18 ppb, than observed previously when flows were less than 500 cfs. S333 S12C S12A S12D S12B S334 8000 7000 A 6000 5000 4000 3000 2000 1000 0 4500 50 4000 B 45 3500 40 3000 35 30 2500 25 2000 20 1500 15 1000 10 500 5 0 0 Flow (cfs) FWMC Phosphorus Jun-03 May-03 Apr-03 Mar-03 Feb-03 Jan-03 Dec-02 Nov-02 Oct-02 Sep-02 Aug-02 Jul-02 Jun-02 May-02 Apr-02 Mar-02 Feb-02 Jan-02 Dec-01 Nov-01 Oct-01 Sep-01 Aug-01 Jul-01 Jun-03 May-03 Apr-03 Mar-03 Feb-03 Jan-03 Dec-02 Nov-02 Oct-02 Sep-02 Aug-02 Jul-02 Jun-02 May-02 Apr-02 Mar-02 Feb-02 Jan-02 Dec-01 Nov-01 Oct-01 Sep-01 Aug-01 Jul-01 Total Phosphorus (ppb) Daily Flow (cfs) Daily Flow (cfs) Figure 4. A. Daily flows into Shark River Slough by structure. B. The relationship between daily flow at Shark River Slough structures and the corresponding flow-weighted mean total phosphorus concentrations for individual sampling events. Taylor Slough and the Coastal Basins Under the Consent Decree, a single total phosphorus long-term limit of 11 ppb, to be met by December 31, 2006, was set for the two points of inflow to Taylor Slough (S332 and S175) and the inflow point to the Coastal Basins (S18C). The 11 ppb limit applies to the water year ending September 30. C-111 Project Structures and Detention Areas Beginning in August 1999, structure S332D, a new pump station constructed by the U.S. Army Corps of Engineers (USACE), began operation. The structure is adjacent to spillway S174 and pumps water from the L31N canal into the L31W canal. The S332D and S174 structures became the new inflow compliance monitoring sites for Taylor Slough on October 1, 1999, replacing S332 and S175. The USACE completed construction of the remaining C-111 project structures and detention areas along the eastern boundary of the ENP in June 2002. The project was authorized by the USACE in 1995 to restore more natural hydrologic conditions in Taylor Slough and to maintain flood protection to the east of the L31N and C-111 canals. Project facilities consist of pump stations S332B, S332C and S332D, Detention Cells 1 through 5, a Connector Cell between cells 2 and 3, a Flow Way Cell originating at Berm 3 of Cell 5, and four emergency overflow structures (Figure 5). The Flow Way Cell is the only surface water routine discharge location to the ENP from this project. The construction of these facilities was accelerated to respond to U.S. Fish and Wildlife requirements to give immediate relief to water conditions that threaten the Cape Sable Seaside Sparrow, an endangered species. The USACE signed a Record of Decision on July 2, 2002 that authorizes the implementation of an Interim Operational Plan (IOP) to govern the operation of the new facilities. Since July 31, 2002, the USACE has been operating the project under Emergency Orders issued by the Florida Department of Environmental Protection (FDEP). The USACE and the South Florida Water Management District (District) will monitor the implementation of the IOP under the terms and conditions of the C- 111 Project Cooperation Agreement executed in 1995. The USACE has implemented a monitoring plan approved by FDEP that assesses the hydrologic, environmental, and surface and ground water quality changes that may occur as a result of the IOP. The monitoring plan treats the detention areas as a single project with five cells, three inflows and a single outflow to ENP. Only Emergency Overflows EO2 and EO4 would discharge into ENP if utilized. Overflows have periodically occurred at EO2 between September 2001 and September 2003. Data from these overflows are presented graphically beginning on page 16 this report. Discharges from Emergency Overflows EO1 and EO3 would flow onto District property and eventually into the L31N Canal. The majority of the water pumped into the detention cells, as well as rainfall, is expected to seep into the Biscayne Aquifer directly below the project site and provide a hydrologic “curtain” to reduce ground water seepage in an easterly direction from ENP. Until FDEP issues an operating permit to the District and approves the District’s monitoring plan, the District will continue to report data from S332D and S174 to determine compliance with the Consent Decree requirements as described in the following section. Cell 1 Emergency Overflow EO1 Cell 2 S332B Emergency Overflow EO2 (for S332B West detention area) Everglades National Park Culvert C1 Connector Cell L-31N Cell 3 Culvert C2 S332C Emergency Overflow EO3 N Head Cell S332D Inflow Structure Outflow Emergency Overflow Berm B1 Cell 4 Emergency Overflow EO4 Berm B2 Cell 5 Outflow Flow Way Cell Berm B3 Figure 5. C-111 Project Facilities. Compliance with Consent Decree Inflow concentrations of total phosphorus to the Everglades National Park through Taylor Slough and the Coastal Basins are compared to the 11 ppb limit at the end of each water year using data from both the old (S175, S332, S18C) and new (S174, S332D, S18C) combinations of structures (Figure 6a). The bars in Figure 6a represent the flow-weighted mean total phosphorus concentrations from S332, S175 and S18C for water years 1989 through 2002. The diamond point values for water years 1999 through 2002 represent the new combination of structures. Figure 6b presents the 12-month moving average and individual sampling event flow-weighted mean total phosphorus concentrations at the S174, S332D and S18C structures. Total phosphorus and flow data from both sets of structures presented in prior editions of this report through December 2001 (April 2002 report) showed that, beginning October 2000, the 12-month moving total flow for S332D, S174 and S18C was consistently greater than flow at S332, S175 and S18C. There was also a shift in flow-weighted mean total phosphorus concentration data whereby S332D, S174 and S18C concentrations became equal to and then consistently lower than the concentrations at S332, S175 and S18C. These changes reflected the switch made from S332 to S332D for water delivery to Taylor Slough between July 3 and July 5, 2000. Consequently, as of the July 2002 report, only S332D, S174 and S18C data are presented for monthly tracking of data in Figure 6b. The 12-month flow-weighted mean concentrations for April, May and June 2003 were 5.8, 5.8 and 5.6 ppb, respectively, for the combined flow through S174, S332D and S18C (Table 3). The Consent Decree stipulates that the percent of flow-weighted mean total phosphorus concentrations greater than 10 ppb from each sampling event in any 12-month period must not exceed a fixed guideline of

Shark River Slough Total Phosphorus Concentration Compliance Tracking. The daily flows through the individual Shark River Slough structures and S334 from July 2001 October 2000 through June 2003 September 2002 are presented in Figure 4a. Since mid- November 2002 inflows to Shark River Slough have been A sharp increase in flow through S333 and S12D. Beginning all structures began in mid-January 2003 a large proportion of the flow in the L29 Canal was released late June 2002. Total daily flows exceeded 2000 cfs from the system early July through S334 due to above-average rainfall. This condition lasted until mid-JuneSeptember. The relationship between the sum of the daily flows at Shark River Slough structures and the corresponding flow-weighted mean total phosphorus concentrations concentration for individual sampling events is presented in Figure 4b. Values for Water Years 2001 and 2002 follow the strong inverse relationship between flow and Higher flows correlate well with lower levels of total phosphorus concentration expected for waters entering the Park through Shark River Slough. However, during the un-seasonal rainfall conditions that occurred from February through June 2003, total phosphorus concentrations were greater and more variable, 9 to 18 ppb, than observed previously when flows were less than 500 cfsphosphorus. S333 S12D S12C S12B S12A S12D S12B S334 8000 7000 A 6000 5000 4000 3000 2000 1000 0 4500 50 4000 B 45 3500 40 3000 35 30 2500 25 2000 20 1500 15 1000 10 500 5 0 0 Flow (cfs) FWMC Phosphorus Jun-03 May-03 Apr-03 Mar-03 Feb-03 Jan-03 Dec-02 Nov-02 Oct-02 Sep-02 Aug-02 Jul-02 Jun-02 May-02 Apr-02 Mar-02 Feb-02 Jan-02 Dec-01 Nov-01 Oct-01 Sep-01 Aug-01 Jul-01 Jun-03 May-03 Apr-03 Mar-03 Feb-03 Jan-03 Dec-02 Nov-02 Oct-02 Jun-01 May-01 Apr-01 Mar-01 Feb-01 Jan-01 Dec-00 Nov-00 Oct-00 Sep-02 Aug-02 Jul-02 Jun-02 May-02 Apr-02 Mar-02 Feb-02 Jan-02 Dec-01 Nov-01 Oct-01 Sep-01 Aug-01 Jul-01 Jun-01 May-01 Apr-01 Mar-01 Feb-01 Jan-01 Dec-00 Nov-00 Oct-00 Total Phosphorus (ppb) Daily Flow (cfs) Daily Flow (cfs) Figure 4. A. Daily flows into Shark River Slough by structure. B. The relationship between daily flow at Shark River Slough structures and the corresponding flow-weighted mean total phosphorus concentrations for individual sampling events. Taylor Slough and the Coastal Basins Under the Consent Decree, a single total phosphorus long-term limit of 11 ppb, to be met by December 31, 2006, was set for the two points of inflow to Taylor Slough (S332 and S175) and the inflow point to the Coastal Basins (S18C). The 11 ppb limit applies to the water year ending September 30. C-111 Project Structures and Detention Areas Beginning in August 1999, structure S332D, a new pump station constructed by the U.S. Army Corps of Engineers (USACE), began operation. The structure is adjacent to spillway S174 and pumps water from the L31N canal into the L31W canal. The S332D and S174 structures became the new inflow compliance monitoring sites for Taylor Slough on October 1, 1999, replacing S332 and S175. The USACE completed construction of the remaining C-111 project structures and detention areas along the eastern boundary of the ENP in June 2002. The project was authorized by the USACE in 1995 to restore more natural hydrologic conditions in Taylor Slough and to maintain flood protection to the east of the L31N and C-111 canals. Project facilities consist of pump stations S332B, S332C and S332D, Detention Cells 1 through 5, a Connector Cell between cells 2 and 3, a Flow Way Cell originating at Berm 3 of Cell 5, and four emergency overflow structures (Figure 5). The Flow Way Cell is the only surface water routine discharge location to the ENP from this project. The construction of these facilities was accelerated to respond to U.S. Fish and Wildlife requirements to give immediate relief to water conditions that threaten the Cape Sable Seaside Sparrow, an endangered species. The USACE signed a Record of Decision on July 2, 2002 that authorizes the implementation of an Interim Operational Plan (IOP) to govern the operation of the new facilities. Since July 31, 2002, the USACE has been operating the project under Emergency Orders issued by the Florida Department of Environmental Protection (FDEP). The USACE and the South Florida Water Management District (District) will monitor the implementation of the IOP under the terms and conditions of the C- 111 Project Cooperation Agreement executed in 1995. The USACE has implemented a monitoring plan approved by FDEP that assesses the hydrologic, environmental, and surface and ground water quality changes that may occur as a result of the IOP. The monitoring plan treats the detention areas as a single project with five cells, three inflows and a single outflow to ENP. Only Emergency Overflows EO2 and EO4 would discharge into ENP if utilized. Overflows have periodically occurred at EO2 between September 2001 and September 2003. Data from these overflows are presented graphically beginning on page 16 this report. Discharges from Emergency Overflows EO1 and EO3 would flow onto District property and eventually into the L31N Canal. The majority of the water pumped into the detention cells, as well as rainfall, is expected to seep into the Biscayne Aquifer directly below the project site and provide a hydrologic “curtain” to reduce ground water seepage in an easterly direction from ENP. Until FDEP issues an operating permit to the District and approves the District’s monitoring plan, the District will continue to report data from S332D and S174 to determine compliance with the Consent Decree requirements as described in the following section. Cell 1 Emergency Overflow EO1 Cell 2 S332B Emergency Overflow EO2 (for S332B West detention area) Everglades National Park Culvert C1 Connector Cell L-31N Cell 3 Culvert C2 S332C Emergency Overflow EO3 N Head Cell S332D Inflow Structure Outflow Emergency Overflow Berm B1 Cell 4 Emergency Overflow EO4 Berm B2 Cell 5 Outflow Flow Way Cell Berm B3 Figure 5. C-111 Project Facilities. Compliance with Consent Decree Inflow concentrations of total phosphorus to the Everglades National Park through Taylor Slough and the Coastal Basins are compared to the 11 ppb limit at the end of each water year using data from both the old (S175, S332, S18C) and new (S174, S332D, S18C) combinations of structures (Figure 6a). The bars in Figure 6a represent the flow-weighted mean total phosphorus concentrations from S332, S175 and S18C for water years 1989 through 2002. The diamond point values for water years 1999 through 2002 represent the new combination of structures. Figure 6b presents the 12-month moving average and individual sampling event flow-weighted mean total phosphorus concentrations at the S174, S332D and S18C structures. Total phosphorus and flow data from both sets of structures presented in prior editions of this report through December 2001 (April 2002 report) showed that, beginning October 2000, the 12-month moving total flow for S332D, S174 and S18C was consistently greater than flow at S332, S175 and S18C. There was also a shift in flow-weighted mean total phosphorus concentration data whereby S332D, S174 and S18C concentrations became equal to and then consistently lower than the concentrations at S332, S175 and S18C. These changes reflected the switch made from S332 to S332D for water delivery to Taylor Slough between July 3 and July 5, 2000. Consequently, as of the July 2002 report, only S332D, S174 and S18C data are presented for monthly tracking of data in Figure 6b. The 12-month flow-weighted mean concentrations for April, May and June 2003 were 5.8, 5.8 and 5.6 ppb, respectively, for the combined flow through S174, S332D and S18C (Table 3). The Consent Decree stipulates that the percent of flow-weighted mean total phosphorus concentrations greater than 10 ppb from each sampling event in any 12-month period must not exceed a fixed guideline of.

Shark River Slough Total Phosphorus Concentration Compliance Tracking. The daily flows through the individual Shark River Slough structures and S334 from July 2001 through June 2003 are presented in Figure 4a. Since mid- November 2002 inflows to Shark River Slough have been through S333 and S12D. Beginning in mid-January 2003 a large proportion of the flow in the L29 Canal was released from the system through S334 due to above-average rainfall. This condition lasted until mid-June. The relationship between the sum of the daily flows at Shark River Slough structures and corresponding flow-weighted mean total phosphorus concentrations for individual sampling events is presented in Figure 4b. Values for Water Years 2001 and 2002 follow the strong inverse relationship between flow and total phosphorus concentration expected for waters entering the Park through Shark River Slough. However, during the un-seasonal rainfall conditions that occurred from February through June 2003, total phosphorus concentrations were greater and more variable, 9 to 18 ppb, than observed previously when flows were less than 500 cfs. S333 S12C S12A S12D S12B S334 8000 7000 A 6000 5000 4000 3000 2000 1000 0 4500 50 4000 B 45 3500 40 3000 35 30 2500 25 2000 20 1500 15 1000 10 500 5 0 0 Flow (cfs) FWMC Phosphorus Jun-03 May-03 Apr-03 Mar-03 Feb-03 Jan-03 Dec-02 Nov-02 Oct-02 Sep-02 Aug-02 Jul-02 Jun-02 May-02 Apr-02 Mar-02 Feb-02 Jan-02 Dec-01 Nov-01 Oct-01 Sep-01 Aug-01 Jul-01 Jun-03 May-03 Apr-03 Mar-03 Feb-03 Jan-03 Dec-02 Nov-02 Oct-02 Sep-02 Aug-02 Jul-02 Jun-02 May-02 Apr-02 Mar-02 Feb-02 Jan-02 Dec-01 Nov-01 Oct-01 Sep-01 Aug-01 Jul-01 Total Phosphorus (ppb) Daily Flow (cfs) Daily Flow (cfs) Figure 4. A. Daily flows into Shark River Slough by structure. B. The relationship between daily flow at Shark River Slough structures and the corresponding flow-weighted mean total phosphorus concentrations for individual sampling events. Taylor Slough and the Coastal Basins Under the Consent Decree, a single total phosphorus long-term limit of 11 ppb, to be met by December 31, 2006, was set for the two points of inflow to Taylor Slough (S332 and S175) and the inflow point to the Coastal Basins (S18C). The 11 ppb limit applies to the water year ending September 30. C-111 Project Structures and Detention Areas Beginning in August 1999, structure S332D, a new pump station constructed by the U.S. Army Corps of Engineers (USACE), began operation. The structure is adjacent to spillway S174 and pumps water from the L31N canal into the L31W canal. The S332D and S174 structures became the new inflow compliance monitoring sites for Taylor Slough on October 1, 1999, replacing S332 and S175. The USACE completed construction of the remaining C-111 project structures and detention areas along the eastern boundary of the ENP in June 2002. The project was authorized by the USACE in 1995 to restore more natural hydrologic conditions in Taylor Slough and to maintain flood protection to the east of the L31N and C-111 canals. Project facilities consist of pump stations S332B, S332C and S332D, Detention Cells 1 through 5, a Connector Cell between cells 2 and 3, a Flow Way Cell originating at Berm 3 of Cell 5, and four emergency overflow structures (Figure 5). The Flow Way Cell is the only surface water routine discharge location to the ENP from this project. The construction of these facilities was accelerated to respond to U.S. Fish and Wildlife requirements to give immediate relief to water conditions that threaten the Cape Sable Seaside Sparrow, an endangered species. The USACE signed a Record of Decision on July 2, 2002 that authorizes the implementation of an Interim Operational Plan (IOP) to govern the operation of the new facilities. Since July 31, 2002, the USACE has been operating the project under Emergency Orders issued by the Florida Department of Environmental Protection (FDEP). The USACE and the South Florida Water Management District (District) will monitor the implementation of the IOP under the terms and conditions of the C- 111 Project Cooperation Agreement executed in 1995. The USACE has implemented a monitoring plan approved by FDEP that assesses the hydrologic, environmental, and surface and ground water quality changes that may occur as a result of the IOP. The monitoring plan treats the detention areas as a single project with five cells, three inflows and a single outflow to ENP. Only Emergency Overflows EO2 and EO4 would discharge into ENP if utilized. Overflows have periodically occurred at EO2 between September 2001 and September 2003. Data from these overflows are presented graphically beginning on page 16 this report. Discharges from Emergency Overflows EO1 and EO3 would flow onto District property and eventually into the L31N Canal. The majority of the water pumped into the detention cells, as well as rainfall, is expected to seep into the Biscayne Aquifer directly below the project site and provide a hydrologic “curtain” to reduce ground water seepage in an easterly direction from ENP. Until FDEP issues an operating permit to the District and approves the District’s monitoring plan, the District will continue to report data from S332D and S174 to determine compliance with the Consent Decree requirements as described in the following section. Cell 2 Cell 1 Emergency Overflow EO1 Cell 2 S332B Emergency Overflow EO2 (for S332B West detention area) Everglades National Park Culvert C1 Connector Cell L-31N Cell 3 Culvert C2 S332C Emergency Overflow EO3 N Head Cell S332D Cell 4 Inflow Structure Outflow Emergency Overflow Berm B1 Cell 4 Emergency Overflow EO4 Berm B2 Cell 5 Outflow Flow Way Cell Berm B3 Figure 5. C-111 Project Facilities. Compliance with Consent Decree Inflow concentrations of total phosphorus to the Everglades National Park through Taylor Slough and the Coastal Basins are compared to the 11 ppb limit at the end of each water year using data from both the old (S175, S332, S18C) and new (S174, S332D, S18C) combinations of structures (Figure 6a). The bars in Figure 6a represent the flow-weighted mean total phosphorus concentrations from S332, S175 and S18C for water years 1989 through 2002. The diamond point values for water years 1999 through 2002 represent the new combination of structures. Figure 6b presents the 12-month moving average and individual sampling event flow-weighted mean total phosphorus concentrations at the S174, S332D and S18C structures. Total phosphorus and flow data from both sets of structures presented in prior editions of this report through December 2001 (April 2002 report) showed that, beginning October 2000, the 12-month moving total flow for S332D, S174 and S18C was consistently greater than flow at S332, S175 and S18C. There was also a shift in flow-weighted mean total phosphorus concentration data whereby S332D, S174 and S18C concentrations became equal to and then consistently lower than the concentrations at S332, S175 and S18C. These changes reflected the switch made from S332 to S332D for water delivery to Taylor Slough between July 3 and July 5, 2000. Consequently, as of the July 2002 report, only S332D, S174 and S18C data are presented for monthly tracking of data in Figure 6b. The 12-month flow-weighted mean concentrations for April, May and June 2003 were 5.8, 5.8 and 5.6 ppb, respectively, for the combined flow through S174, S332D and S18C (Table 3). The Consent Decree stipulates that the percent of flow-weighted mean total phosphorus concentrations greater than 10 ppb from each sampling event in any 12-month period must not exceed a fixed guideline of

Shark River Slough Total Phosphorus Concentration Compliance Tracking. The daily flows through the individual Shark River Slough structures and S334 from July April 2001 through June March 2003 are presented in Figure 4a. Since mid- Beginning in November 2002 inflows to a sharp decrease in flow occurred at all structures. Flows were low between mid-November and mid-December, reaching a minimum of 161 cfs/day on December 16. Thereafter, flows into Shark River Slough have been steadily increased to a maximum of 953 cfs/day on January 9, 2003 and then slowly declined through S333 and S12D. Beginning in mid-January 2003 a large proportion the end of the flow in the L29 Canal March. Water was released removed from the system via S334 from January 17 through S334 due to above-average rainfall. This condition lasted until mid-JuneMarch 31, 2003. The relationship between the sum of the daily flows at Shark River Slough structures and the corresponding flow-weighted mean total phosphorus concentrations concentration for individual sampling events is presented in Figure 4b. Values for Water Years 2001 and 2002 follow the strong inverse relationship between flow and total phosphorus concentration expected for waters entering the Park through Shark River Slough. However, during the un-seasonal rainfall conditions that occurred from February through June 2003, total phosphorus concentrations were greater and more variable, 9 to 18 ppb, than observed previously when flows were less than 500 cfs. S333 S12C S12A S12D S12B S334 8000 7000 A 6000 5000 4000 3000 2000 1000 0 4500 50 4000 B 3500 45 3500 40 35 3000 35 30 2500 25 2000 20 1500 15 1000 10 500 5 0 0 Flow (cfs) FWMC Phosphorus Jun-03 May-03 Apr-03 Mar-03 Feb-03 Jan-03 Dec-02 Nov-02 Oct-02 Sep-02 Aug-02 Jul-02 Jun-02 May-02 Apr-02 Mar-02 Feb-02 Jan-02 Dec-01 Nov-01 Oct-01 Sep-01 Aug-01 Jul-01 Jun-03 May-03 Apr-03 Jun-01 May-01 Apr-01 Mar-03 Feb-03 Jan-03 Dec-02 Nov-02 Oct-02 Sep-02 Aug-02 Jul-02 Jun-02 May-02 Apr-02 Mar-02 Feb-02 Jan-02 Dec-01 Nov-01 Oct-01 Sep-01 Aug-01 Jul-01 Jun-01 May-01 Apr-01 Total Phosphorus (ppb) Daily Flow (cfs) Daily Flow (cfs) Figure 4. A. Daily flows into Shark River Slough by structure. B. The relationship between daily flow at Shark River Slough structures and the corresponding flow-weighted mean total phosphorus concentrations for individual sampling events. Taylor Slough and the Coastal Basins Under the Consent Decree, a single total phosphorus long-term limit of 11 ppb, to be met by December 31, 2006, was set for the two points of inflow to Taylor Slough (S332 and S175) and the inflow point to the Coastal Basins (S18C). The 11 ppb limit applies to the water year ending September 30. C-111 Project Structures and Detention Areas Beginning in August 1999, structure S332D, a new pump station constructed by the U.S. Army Corps of Engineers (USACE), began operation. The structure is adjacent to spillway S174 and pumps water from the L31N canal into the L31W canal. The S332D and S174 structures became the new inflow compliance monitoring sites for Taylor Slough on October 1, 1999, replacing S332 and S175. The USACE completed construction of the remaining C-111 project structures and detention areas along the eastern boundary of the ENP in June 2002. The project was authorized by the USACE in 1995 to restore more natural hydrologic conditions in Taylor Slough and to maintain flood protection to the east of the L31N and C-111 canals. Project facilities consist of pump stations S332B, S332C and S332D, Detention Cells 1 through 5, a Connector Cell between cells 2 and 3, a Flow Way Cell originating at Berm 3 of Cell 5, and four emergency overflow structures (Figure 5). The Flow Way Cell is the only surface water routine discharge location to the ENP from this project. The construction of these facilities was accelerated to respond to U.S. Fish and Wildlife requirements to give immediate relief to water conditions that threaten the Cape Sable Seaside Sparrow, an endangered species. The USACE signed a Record of Decision on July 2, 2002 that authorizes the implementation of an Interim Operational Plan (IOP) to govern the operation of the new facilities. Since July 31, 2002, the USACE has been operating the project under Emergency Orders issued by the Florida Department of Environmental Protection (FDEP). The USACE and the South Florida Water Management District (District) will monitor the implementation of the IOP under the terms and conditions of the C- 111 Project Cooperation Agreement executed in 1995. The USACE has implemented a monitoring plan approved by FDEP that assesses the hydrologic, environmental, and surface and ground water quality changes that may occur as a result of the IOP. The monitoring plan treats the detention areas as a single project with five cells, three inflows and a single outflow to ENP. Only Emergency Overflows EO2 and EO4 would discharge into ENP if utilized. Overflows have periodically occurred at EO2 between September 2001 and September 2003. Data from these overflows are presented graphically beginning on page 16 this report. Discharges from Emergency Overflows EO1 and EO3 would flow onto District property and eventually into the L31N Canal. The majority of the water pumped into the detention cells, as well as rainfall, is expected to seep into the Biscayne Aquifer directly below the project site and provide a hydrologic “curtain” to reduce ground water seepage in an easterly direction from ENP. Until FDEP issues an operating permit to the District and approves the District’s monitoring plan, the District will continue to report data from S332D and S174 to determine compliance with the Consent Decree requirements as described in the following section. Cell 1 Emergency Overflow EO1 Cell 2 S332B Emergency Overflow EO2 (for S332B West detention area) Everglades National Park Culvert C1 Connector Cell L-31N Cell 3 Culvert C2 S332C Emergency Overflow EO3 N Head Cell S332D Inflow Structure Outflow Emergency Overflow Berm B1 Cell 4 Emergency Overflow EO4 Berm B2 Cell 5 Outflow Flow Way Cell Berm B3 Figure 5. C-111 Project Facilities. Compliance with Consent Decree Inflow concentrations of total phosphorus to the Everglades National Park through Taylor Slough and the Coastal Basins are compared to the 11 ppb limit at the end of each water year using data from both the old (S175, S332, S18C) and new (S174, S332D, S18C) combinations of structures (Figure 6a). The bars in Figure 6a represent the flow-weighted mean total phosphorus concentrations from S332, S175 and S18C for water years 1989 through 2002. The diamond point values for water years 1999 through 2002 represent the new combination of structures. Figure 6b presents the 12-month moving average and individual sampling event flow-weighted mean total phosphorus concentrations at the S174, S332D and S18C structures. Total phosphorus and flow data from both sets of structures presented in prior editions of this report through December 2001 (April 2002 report) showed that, beginning October 2000, the 12-month moving total flow for S332D, S174 and S18C was consistently greater than flow at S332, S175 and S18C. There was also a shift in flow-weighted mean total phosphorus concentration data whereby S332D, S174 and S18C concentrations became equal to and then consistently lower than the concentrations at S332, S175 and S18C. These changes reflected the switch made from S332 to S332D for water delivery to Taylor Slough between July 3 and July 5, 2000. Consequently, as of the July 2002 report, only S332D, S174 and S18C data are presented for monthly tracking of data in Figure 6b. The 12-month flow-weighted mean concentrations for April, May and June 2003 were 5.8, 5.8 and 5.6 ppb, respectively, for the combined flow through S174, S332D and S18C (Table 3). The Consent Decree stipulates that the percent of flow-weighted mean total phosphorus concentrations greater than 10 ppb from each sampling event in any 12-month period must not exceed a fixed guideline of.