40381 Addendum 2.pdf

DATE: September 30, 2024

TO: Prospective Respondents

FROM: LaDonna Johnson, Procurement Specialist

SUBJECT: Addendum 2 to Request for Qualification – Design Build 40381, S-157 Wing Walls and Manatee Overlook Rehabilitation Project

As a result of the non-mandatory pre-submittal conference, the following information is provided. Additionally, some of the information provided under Addendum 1 is revised by this addendum. Please read carefully.

1. The due dates and times remain unchanged: Step One – October 25, 2024, 2:00 pm; and Step Two – December 10, 2024, 2:00 pm.

2. Question: Is this brackish water and does that affect the design?

Answer: The wingwall is in brackish water, and the design must consider this condition to ensure durability and proper material selection.

3. Question: Regarding 5.0 General Design Criteria – could the District provide a copy of the current hydraulic modeling of this structure?

Answer: Attached, please find the Water Control Manual for the Upper St. Johns River Basin (dated 1991). It contains a summary of hydraulic design as well as gate opening curves and discharge rating curves. However, the documentation from the original construction era does not represent current modern hydraulic modeling.

4. Question: Regarding rain delays, it is the Contractor’s responsibility to factor in a reasonable amount of rain days? We would like clarification on this regarding whether recovery days are to be included in this factor. On several occasions we have witnessed a 3” rain event that raises the canal water elevation over a foot and this can take anywhere from 4 to 7 days for the canal to stop flowing over the open slots in the gates at S-157.

Answer: Refer to Paragraph 13 of the Draft Agreement: “The times specified herein for performances include delays that can ordinarily be anticipated due to adverse weather conditions. The District is not obligated to grant an extension of time due to adverse weather conditions unless such conditions rise to the level of Force Majeure.”

5. Question: Can the District provide documentation regarding the amount of flow into the C-54 canal between S-157 and S-96 specifically the base flow of the canal, historical flow data, who is permitted to discharge into the C-54 canal upstream of S-157, and the locations of any culverts, structures, pump stations that discharge into the C-54 canal and their flow capacities?

A spreadsheet with calculated dry season flow data over S-157 from 1990 to 2022 is included, along with the associated rating curve for reference.

Please acknowledge receipt of this Addendum on the PRICE PROPOSAL ACKNOWLEDGMENT FORM provided in the solicitation package.

If you have any questions, please e-mail me at ljohnson@sjrwmd.com.

SEPTEMBER 1991

CENTRAL AND SOUTHERN FLORIDA PROJECT

FOR FLOOD CONTROL AND OTHER PURPOSES

PRELIMINARY WATER CONTROL MANUAL

UPPER ST. JOHNS RIVER BASIN

fr.'l'P.11 lllilill

U. S. ARMY CORPS OF ENGINEERS

JACKSONVILLE DISTRICT SERIAL NO. 09

STRUCTURE 96 CS-96)

Location. S-96 is located on the Sebastian Canal (C-54), approximately 6.2 miles upstream of the State Road 507 Bridge.

Descriotion. S-96 was proposed and built under the 1962 plan of improvement.

The structure is a two-bay, U~shaped gated spillway, has an ogee weir and vertical lift gates and is capable of discharging 6,000 cfs. Page A-96-3 contains the design data for S-96.

Puroose. The spillway was originally designed to hold the C-54 headwater pool elevation between 22.0 and 25.5 ft., NGVD. During large storm events S-96 was to divert flood waters from the Lake Wilmington Reservoir (also known as the Blue Cypress Marsh Conservation Area (BCMCA)) into C-54. The maximum design discharge is 6,000 cfs under SPF conditions. Under the current plan, S-96 is located at the northeastern end of the St. Johns Water Management Area (SJWMA) in L-74E and serves as an outlet into C-54. S-96 will supplement the discharges of S-96B in the release of water from the St. Johns Water Management Area (SJWMA). Releases will be made through S-96 to augment the discharges through S-96B. Gate Openings shall not exceed those shown on the Maximum Allowable Gate Opening Curves shown on Plate A-96-1. Discharge Ratings Curves for the S-96 are found on Plates A-96-2, A-96-3, and A-96-4.

Normal Regulation. The water surface elevation will be seasonally regulated between elevation 22.0 and 23.0 ft., NGVD as shown on the regulation schedule for the St. Johns Water Management Area. S-96B is the main outlet for the SJWMA discharging into the flood plain of the St. Johns River. S-96B will be operated to maintain the optimum stages in the SJWMA. No discharges from S-96 will be made when the SJWMA is in Zone B.

Flood Control. During the Initial Plan, S-96 will be used to control the elevation in Blue Cypress Lake. Discharges through S-96 shall be controlled not to exceed 1500 cfs at S-157 whenever Blue Cypress Lake rises to elevation

25.2 ft., and maximum possible discharge at S-96 and S-157 when Blue Cypress Lake exceeds 25.5 ft., NGVD. During Interim Plans 1 and 2, S-96 can be used to control the elevation in the Blue Cypress Water Conservation Area (BCMCA).

S-96 may be opened when the stage in the BCMCA exceeds 25.0 ft. to permit a discharge not to exceed 1500 cfs at S-157, and the maximum possible discharge when BCMCA exceeds 25.5 ft., NGVD. During Interim Plan 4 (when the Fellsmere Grade has been breached) until project completion, S-96 will be used as follows to control stages in the SJWMA. S-96, S-96B, and S-258 provide sufficient capacity to discharge waters from the SJWMA to reduce the maximum stage and stage duration effects during storm conditions. S-96B is the main outlet for flood control. When the stage in the SJWMA exceeds elevation 25.0 ft., NGVD, discharges will be made through S-96 not to exceed a discharge of 1500 cfs at S-157, and maximum possible discharge at S-96 and S-157 when SJWMA exceeds 25.5 ft., NGVD. Under SPF conditions an estimated 2,299 cfs could be released through S-96. Additional storage of flood waters is provided in the C-54 Retention Area. Water is conveyed to this area through S-258. S-258 has a maximum capacity of 750 cfs. The discharge through S-96 may be proportionately reduced by the discharge through S-258. When the stage in the

A-96-1

SJWMA recedes to Zone B, discharges through S-968 shall be made only for environmental purposes and downstream water supply.

A-96-2

STRUCTURE 96

Summary of Hydraulic Design

Location ----------------------------------------------- Design Conditions

Discharge (cfs) ------------------------------------ Headwater Elevation (ft.) -------------------------- Tailwater Elevation (ft.) ---------------------------

Optimum Condition Headwater Elevation (ft.) -------------------------- Tailwater Elevation (ft.) --------------------------

Maximum Headwater (ft.) ------------------------------- Crest

Shape -------------------------------~--------------- Elevation (ft.)-------------------------------------- Net Length ------------------------------------------

Gates Number ---------------------------------------------- Width X Height (ft.) ----------------~-------------- Clearance Elevation ---------------------------------

Apron Elevation ------------------------------------------ Length ----------------------------------------------

Training Wall Elevation ------------------------------- Riprap

Length (ft.) --------------------------------------- Elevation (ft.) ------------------------------------

Tieback Levee Elevation (ft.) --------------------------

A-96-3

L-74E

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Central and Southern Florida Project

UPPER ST. JOHNS RIVER BASIN

PRELIMINARY WATER CONTROL MANUAL

STRUCTURE 96

DISCHARGE RATING CURVES

September 1991 USAED Jacksonville

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PRELIMINARY WATER CONTROL MANUAL

STRUCTURE 96

DISCHARGE RATING CURVES

September 1991 USAED Jacksonville

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UPPER ST. JOHNS RIVER BASIN

PRELIMINARY WATER CONTROL MANUAL

STRUCTURE 96

DISCHARGE RATING CURVES

September 1991 USAED Jacksonville

S- <76 S\Je.M.E.K'6c fi c :~N T R0L Lt. 0 F L::·v-J

(2 G'AT£S)

Plate A-96-4

STRUCTURE 968 CS-968)

Location. S-968 is located approximately 16 miles south of Melbourne FL, about 2 miles west of S-96 at the intersection of L-74E and L-74N.

Description. S-968 is a LI-shaped spillway, has an ogee weir, a vertical lift gate and a stilling basin to restrict velocities to nonerosive values in the existing canal. S-968 has a maximum design discharge capacity of 1,000 cfs.

The structure is sized to pass the design discharge with the gates full-open with concurrent design headwater and tailwater. Page A-968-3 contains the basic design data for S-968.

Purpose. S-968 is the main outlet for the St. Johns Water Management Area {SJWMA) by allowing discharges of up to 1,000 cfs to be made into the historic flood plain of the St. Johns River and will be supplemented by the discharge capacity of S-96. Thus the St. Johns Water Management Area has an outlet (S-968) for discharging into the historic flood plain, and an outlet {S-96) for discharging to Sebastian Canal {C-54). S-968 will be used to regulate water surface elevations in the SJWMA between 22.0 and 23.0 ft., NGVD for the purposes of preventing overdrainage and providing water supply for agricultural users. S-968 has a maximum design discharge capacity of 1,000 cfs. Under SPF design storm conditions regulated elevations would reach a stage of 25.4 ft.,NGVD. When the stage in the SJWMA is 25.0 ft. releases would also be made through S-96 to the Sebastion Canal (C-54). S-968 is also designed to operate with "reverse flow" capabilities. Plate A-968-1 contains the Discharge Rate Curves for the structure. Velocity vs. Riprap curves for are found on Plate A-968-2.

Normal Regulation. The water surface elevation will be seasonally regulated between elevation 22.0 and 23.0 ft., NGVD as shown on the regulation schedule for the St. Johns Water Management Area. S-968 is the main outlet for the St.

Johns Water Management Area discharging into the flood plain of the St. Johns River. S-968 will be operated to maintain the optimum stages in the SJWMA.

The gate settings for S-968 will be in accordance with the discharge-rating curves. When the stage in the SJWMA is in Zone 8, discharges may be made through S-968 for water supply and environmental purposes.

Flood Control. During Interim Plans 1 and 2, S-968 may be used to permit reverse flows from the 8CMCA to be outlet through S-96 to C-54. In Interim Plan 4 {when the Fellsmere Grade has been breached) through project completion S-968 will be used to control the stages in the SJWMA as follows. S-968, S-96, and S-258 provide sufficient capacity to discharge waters from the SJWMA to reduce the maximum stage and stage duration effects during storm conditions. S-968 is the main outlet for flood control. When the stage in the SJWMA is in Zone A, releases shall be made through S-968. The spillway gate of S-968 should be opened and closed gradually to provide an even transition to the new flow regime and to minimize hydraulic effects downstream. When the stage in the SJWMA is 25.0 ft. releases would also be made through S-96 to C-54. However, the discharges through S-96 may be proportionately reduced by the discharges being made through S-258.

Additional storage of flood waters is provided in the C-54 Retention Area.

Water is conveyed to this area through S-258. When the stage in the SJWMA

A-968-1 recedes to Zone 8, discharges through S-968 shall be made only for environmental purposes and water supply. S~968 will be required to operate under hurricane alert conditions to make discharges to maintain design water surface elevations in the St. Johns Water Management Area.

A-968-2

STRUCTURE 968

Location ---------------------------------------------- Station ------------------------------------------------ Design Conditions

Gate Design Discharge (cfs) ---------------------------------- Headwater Elevation (ft.) ------------------------ Tailwater Elevation (ft.) -------------------------

Stilling Basin Design Discharge (cfs) ------------------------------------ Headwater Elevation (ft.) -------------------------- Tailwater (ft.) -------------------------------------

S.P.F. Condition Discharge (cfs) ------------------------------------ Headwater Elevation (ft.) -------------------------- Tailwater Elevation (ft.) ---------------------------

Optimum Condition Headwater Elevation (ft.) -------------------------- Tailwater Elevation (ft.) ---------------------------

Crest Shape -------------------------------------~--------- Elevation (ft.)----------------------------------~--- Des igri Head (ft.) ·- -- --- -- --- -- --- -- ---- -- -- - -- -- --- - Net Length ------------------------------------------

Gates Number ---------------------------------------------- Width X Height (ft.) ------------------------------- Clearance Elevation -------------------------------- Overflow Slot Elevation -----------------------------

Instrumentation Headwater Recorder and Staff Gage ------------------ Tailwater Recorder and Staff Gage ------------------ Gate Position Recorders -----------------------------

Sti 11 i ng Basin Elevation ------------------------------------------ Length ---------------------------------------------- Endsil l Elevation ---------------------------------- Baffle Block Elevation ----------------------------- Rows of Baffle Blocks -------------------------------

A-96B-3

L-74E 1+00

1,000 25.1 24.7

1,000 22.0 21.0

1,000 25.1 24.7

22.0 - 23.0

Ogee 13.1 12.0 20.0

20.0 x 10.9

26.1

22.0 - 23.5

Yes Yes Yes

11.8

12.8 13.8

STRUCTURE 968

Summary of Hydraulic Design (Continued}

Training Wall Elevation ------------------------------- Channel Section

Upstream Bottom Width (ft.) ------------------------ Upstream Bottom Elevation -------------------------- Upstream Side Slopes ------------------------------- Downstream Bottom Width (ft.) ---------------------- Downstream Bottom Elevation ------------------------ Downstream Side Slopes ------------------------------

Upstream Riprap Length (ft.) --------------------------------------- Protection Elevation -------------------------------

Downstream Riprap Length (ft.) --------------------------------------- Protection Elevation --------------------------------

Protection Elevation -----------------------------------

All elevations are in feet and refer to NGVD.

A-96B-4

25.7

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FREE CONTROLLED FLOW

Central and Southern Florida Project

UPPER ST. JOHNS RIVER BASIN

PRELIHINARY WATER CONTROL MANUAL

STRUCTURE 968

DISCHARGE RATING CURVES

September 1991 USAED Jacksonville

Plate A-968-1

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DI STANCE FROM STRUCTURE-FEET

Central and Southern Florida Project I

. UPPER ST. JOHNS RIVER BASIN-

PRELIMINARY WATER CONTROL MANUAL

VELOCITY vs. RIPRAP

STRUCTURE 968

September 1991 USA ED Jacksonville

Plate A-968-2 ..

STRUCTURE 96C CS-96Cl

Location. S-96C is located in L-74W, at the northeast corner of the BCMCA.

Descriotion. S-96C is a U-shaped spillway, has an ogee weir, vertical lift gate, and a stilling basin to restrict velocities to nonerosive values in the existing canal. The structure has a design discharge of 1,500 cfs. The structure is sized to pass the design discharge with the gates full-open with concurrent design headwater and tailwater. Page A-96C-2 shows basic design data for S-96C.

Purpose. S-96C serves as the main outlet for the Blue Cypress Marsh Conservation Area {BCMCA) and provides regulatory and flood control discharges of up to 1,500 cfs from the BCMCA to the historic floodplain of the St. Johns River. Discharges will be made to maintain design stages in the BCMCA. The structure operation will allow regulation of the BCMCA to prevent overdrainage. The normal regulation will vary water surface elevations between 23.0 and 24.5 ft., NGVD. Under design storm conditions, discharges from this S-96C will be augmented by discharges through S-250A, S-2508, and S-250C. The structure will be required to operate under hurricane alert conditions to maintain design stages in the BCMCA. Plates A-96C-l and A-96C-2 contain the Discharge Rating Curves. Velocity vs. Riprap curves are found on Plate A-96C-3.

Normal Regulation. The BCMCA will be seasonally regulated between elevation

23.0 and 24.5 ft., NGVD as shown on the the regulation schedule. S-250A, S-2508, and S-250C will permit water to pass downstream when the water surface elevation is above 22.0 ft., NGVD, thus helping to maintain downstream flows under normal daily conditions. Risers for the culverts are set at elevation

22.0 ft., NGVD. Risers may be removed in the future to provide drawdown capabilities. S-96C will serve as the major outlet for the BCMCA and will regulate the water surface elevation in the conservation area. S-96C is operated to maintain optimum stages in the BCMCA.

Flood Control. During Interim Plans 2 and 3, S-96C will be used to maintain the stages in the BCMCA around elevation 23.0 ft., NGVD. During Interim Plan 4 through project completion S-96C will be used to control the stages in the BCMCA as follows. The project works {S-96C and S-250A, B, and C) provide sufficient capacity to discharge waters from the BCMCA to reduce the maximum stage and stage duration effects during storm conditions. When water levels in Blue Cypress Lake are in Zone A, S-96C will be opened to release water downstream into the flood plain. The spillway gate should be opened and closed gradually to provide an even transition to the new flow regime and to minimize hydraulic effects downstream. In addition, the culvert structures will discharge a maximum of 300 cfs when the water surface elevation reaches

25.0 ft., NGVD. Water would also begin to flow over the weirs {S-250A, B, and C) when the water surface elevation in the BCMCA exceeds 25.0 ft., NGVD. Once the water surface elevation recedes to Zone B, S-96C will be operated for environmental purposes or water supply. S-96C will be required to operate under hurricane alert conditions. Discharges during this time would be made to maintain design stages in the BCMCA and to make releases to the St. Johns River flood plain.

A-96C-l

STRUCTURE 96C

Location ----------------------------------------------- L-74W Station ------------------------------------------------ 1+00 Design Conditions

Gate Design Discharge (cfs) ---------------------------------- Headwater Elevation (ft.) ------------------------ Tailwater Elevation (ft.) -------------------------

Stilling Basin Design Discharge (cfs) ------------------------------------ Headwater Elevation (ft.) -------------------------- Tailwater (ft.) -------------------------------------

S.P.F. Condition Discharge (cfs) ------------------------------------ Headwater Elevation (ft.) -------------------------- Tailwater Elevation (ft.} ---------------------------

Optimum Condition

1,500 25.2 24.6

1,500 25.0 21.0

1,500 25.2 24.6

Headwater Elevation (ft.} --------------------------- 23.0 - 24.5 Tailwater Elevation (ft.} ---------------------------

Crest Shape ----------------------------------------------- Elevation (ft.}-------------------------------------- Design Head (ft.} ----------------------------------- Net Length ------------------------------------------

Gates

Ogee 11.8 13.4 25.0

Number ---------------------------------------------- 1 Width X Height (ft.} -------------------------------- 25.0 X 13.7 Clearance Elevation --------------------------------- 27.6 Overflow Slot Elevation ----------------------------- 23.0 - 25.0

Instrumentation Headwater Recorder and Staff Gage ------------------ Tailwater Recorder and Staff Gage ------------------ Gate Position Recorders -----------------------------

Stilling Basin Elevation ------------------------------------------ Length ---------------------------------------------- Endsil l Elevation ---------------------------------- Baffle Block Elevation ----------------------------- Rows of Baffle Blocks -------------------------------

Training Wall Elevation ------------------------------- Channel Section

A-96C-2

Yes Yes Yes

9.8 20.0 10.8 11.7

24.8

STRUCTURE 96C

Summary of Hydraulic Design {Continued)

Upstream Bottom Width (ft.) ------------------------ Upstream Bottom Elevation --------------------~----- Upstream Side Slopes ------------------------------- Downstream Bottom Width (ft.) ---------------------- Downstream Bottom Elevation ------------------------ Downstream Side Slopes ------------------------------

Upstream Riprap length (ft.) --------------------------------------- Protection Elevation -------------------------------

Downstream Riprap length (ft.) ---------------------------------------- Protection Elevation -------------------------------

Protection Elevation -----------------------------------

All elevations are in feet and refer to NGVD.

A-96C-3

1 on 3

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20.0 29.6

90.0 27.8 30.6

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SUBMERGED UNCONTROLLED FLOW

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= APPROACH VELOCITY

Central and Southern Florida Project

UPPER ST. JOHNS RIVER BASIN

PRELIMINARY WATER CONTROL MANUAL

STRUCTURE 96C

DISCHARGE RATING CURVES

-Plate A-96C-2 t;

&L. -• ...

I

Cl

10.0

9.0

8.0

7.0

6.0

&.O

4.0

3.0

2.0

1.0

.9

.8

.7

.6

.5

.4

.3

.2

I I

I I

20 30 40

I I

I I

I

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I

I

I I

I

I i/

4') e,,·

I

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SUBMERGED CONTROLLED FLOW

DISCHARGE-CFS

8X> IOOO 2000 ~00 4000 S>OO 7000

BASIS FOR DISCHARGE RATING CURVES

SUBMERGED CONTRObLED FLOW

BASED ON ORIFICE FORMULA

Q• CA ~29 AH

Cc 0.75

A• GATE OPENING X 20.0'

Central and Southern Florida Project

UPPER ST. JOHNS RIVER BASIN

PRELIMINARY WATER CONTROL MANUAL

STRUCTURE 96C

DISCHARGE RATING CURVES

Plate A-96C-l

Q = 1500

HW = 25.2

20'

RIPRAP

20 15 10

UPSTREAM

6 6

5 5 z u

UJ

4 V') 4

0::

UJ

a..

1-

UJ

3 UJ 3

I.I..

I

1-u 0 2 ...J

UJ

I- I i

0 0

Q = 1500

TW= 21.0

90'

RIPRAP

20 40 60 80 100 120

DOWNSTREAM

01 STANCE FROM STR UC TU RE - FEET

Central and Southern Florida Project

UPPER ST. JOHNS RIVER BASIN

PRELIMINARY WATER CONTROL MANUAL

VELOCITY VS. RIPRAP

STRUCTURE 96C

. September 1991 USAED Jacksonville

Plate A-96C-3

STRUCTURE 960 CS-960)

Location. S-96D is located approximately 5 miles south of S-96 along L-75.

S-96D is constructed in the southeast corner of the SJWMA, in canal C-65, which connects the Blue Cypress Water Management Area (BCWMA) to the St. Johns Water Management Area (SJWMA).

Descriotion. S-96D is a LI-shaped spillway structure, has an ogee weir, a vertical lift gate, and a stilling basin to restrict velocities to nonerosive values in the St. Johns Water Management Area. The design discharge is 1,000 cfs. The structure is sized to pass the design discharge with the gates full open with concurrent design headwater and tailwater. Page A-96D-2 shows the basic design data for S-96D.

Puroose. S-96D is the primary outlet for the Blue Cypress Water Management Area (BCWMA). The structure will prevent overdrainage of the BCWMA and provide water supply for agricultural users. The regulation will vary water surface elevations between 24.5 and 25.5 ft., NGVD. D·ischarges from up to 1,000 cfs pass into Canal 65. Adjacent to S-96D is an existing SJRWMD culvert structure, S-3. Under design conditions both structures are used to discharge water into the SJWMA, with a combined discharge of 1,600 cfs (1,000 cfs from S-96D and 600 cfs from S-3). S-96D is sized to pass design discharge with the gates full open and with concurrent design headwater and tailwater elevations.

Plate A-96D-l contains the Discharge Rating Curves for S-96D. The Velocity

vs. Riprap curves are found on Plate A-96D-2. Plate A-96D-3 contains the discharge rating curve for the culvert owned by SJRWMD (S-3).

Normal Regulation. The normal yearly regulation of the BCWMA will vary seasonally between elevation 24.5 and 25.5 ft., NGVD as shown on the regulation schedule. Regulation control of the BCWMA will be maintained by S-96D. The gate settings shall be in accordance with the discharge-rate curves. When in Zone B, discharges through S-96D will be for only environmental purposes or downstream water supply. S-251 is equipped with slide gates to permit control of the water in the eastern and western section of the BCWMA. Normally, the gates of S-251 will be left open to allow the head on both sides of the BCWMA to be equal.

Flood Control. During Interim Plans 2, 3, and 4, S-96D will normally be closed to prevent flows from the SJWMA into the BCWMA. During Interim Plan 5 S-96D will be used as follows. S-96D and S-254 provide sufficient capacity to discharge waters from the BCWMA to reduce the maximum stage and stage duration effects during storm conditions. When the stage in the BCWMA is in Zone A, releases shall be initiated through S-96D. The spillway gate should be opened and closed gradually to provide an even transition to the new flow regime and to minimize hydraulic effects downstream. Once the water surface elevation recedes to Zone B, S-96D discharges should only be for environmental purposes or downstream water supply. Discharges through S-96D may be restricted by high water surface elevations in the adjacent SJWMA. During high stages in the BCWMA, discharges of S-96D maybe supplemented by adjacent existing Culvert Structure S-3 located in the southeast corner of the St. Johns Water Management Area (SJWMA). In addition, S-254 will discharge waters from the BCWMA to the Blue Cypress Marsh Conservation Area (BCMCA) when the water

A-96D-l surface elevation exceeds 26.6 ft., NGVO. S-960 will be required to operate under hurricane alert conditions in order to maintain design stages in the

BCWMA.

A-960-2

STRUCTURE 960

Location ---------------------------------------------- Station ------------------------------------------------ Design Conditions

Gate Design Discharge (cfs) ---------------------------------- Headwater Elevation (ft.) ------------------------ Tailwater Elevation (ft.) -------------------------

Stilling Basin Design Discharge (cfs) ------------------------------------ Headwater Elevation (ft.) -------------------------- Tailwater (ft.) -------------------------------------

5.P.F. Condition Discharge (cfs) ------------------------------------ Headwater Elevation (ft.) -------------------------- Tailwater Elevation (ft.) ---------------------------

Optimum Condition Headwater Elevation (ft.) -------------------------- Tailwater Elevation (ft.) ---------------------------

Crest Shape ----------------------------------------------- Elevation (ft.)-------------------------------------- Design Head (ft.) ---------------------------------- Net Length ------------------------------------------

Gates · Number ---------------------------------------------- Width X Height (ft.) ------------------------:------ Clearance Elevation -------------------------------- Overflow Slot Elevation -----------------------------

Instrumentation Headwater Recorder and Staff Gage ------------------ Tailwater Recorder and Staff Gage ------------------ Gate Position Recorders -----------------------------

Stilling Basin Elevation ------------------------------------------ Length ---------------------------------------------- Endsill Elevation ---------------------------------- Baffle Block Elevation ----------------------------- Rows of Baffle Blocks -------------------------------

Training Wall Elevation --------------------------------

A-96D-3

L-74W 0+00

1,000 26.35 25.35

1,000 26.35 22.0

1,000 26.35 25.35

24.5 - 25.5

22.0 - 23.0

Ogee 15.3 10.8 15.0

15.0 x 12.6

27.4

24.5 - 26.0

Staff Gage Staff Gage

Yes

6.0 21.0 7.4 7.9

26.4

STRUCTURE 960

Summary of Hydraulic Design (Continued)

Channel Section Upstream Bottom Width (ft.) ------------------------ Upstream Bottom Elevation -------------------------- Upstream Side Slopes ------------------------------- Downstream Bottom Width (ft.) ---------------------- Downstream Bottom Elevation ------------------------ Downstream Side Slopes ------------------------------

Upstream Riprap Length (ft.) --------------------------------------- Protection Elevation -------------------------------

Downstream Riprap Length (ft.) ------------------------------------~--- Protection Elevation -------------------------------

Protection Elevation -----------------------------------

SJRWMD CULVERT STRUCTURE S-3

(Adjacent to S-96D)

Location ----------------------------------------------- Design Condition

Discharge (cfs) ------------------------------------ Headwater Elevation (ft.) -------------------------- Tailwater Elevation (ft.) ---------------------------

Culvert · Number ---------------------------------------------- Size (Inches) -------------------------------------- Invert Elevation ----------------------------------- Type of Control -------------------------------------

All elevations are in feet and refer to NGVD.

A-960-4

I

I on 3 on 3

29.4

28.4 30.4

Canal 65

26.35 25.35

15.0 Slidegate

10.0 9.0 8.0 7.0

6.0

5.0

4.0

'3.0

1-

UJ 2.0

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I I ;s :r: I. 0 ;.o.9 '<J 0.8

0.1

0.6

0.5

0.4

0.2

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I

30 40 50 60 708090100 200 300 400 500600 800 1000

DISCHARGE C.FS.

SUBMERGED CONTROLLED FLOW

8Allt ,0. OllCtU.••t •A'rlMt CUlt'tl S

£QU&noNS, ~res ... D S'AlllOL s IA UD OH [Ill

1110-Z-•601 AND •~U C"AATS

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7.0

5.0

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fo-l :c 10 :r: 0.9 ; 0.8 <J 0.7

0.6

0.5

0.4

0.3

0.2

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I 1;;,I I/;, 300 400 500 600 800 1000

DISCHARGE C.F.S.

2000 3000

SUBMERGED UNCONTROLLED FLOW

IUM"81D UNtX* IACJl LEX> fl\.O! UllD ON p• AUIUlllON'I

'9R!!IM

Q• KA y-z-,-A-H-+Y-1 ~I

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REE UNCONTROLLED

DISCHARGE

CREST ELEVATION=l5.3

FREE

iOOO 1500 2000 2500

DISCHARGE C. F. S.

CONTROLLED FLOW

Central and Southern Florida Project

UPPER ST. JOHNS RIVER BASIN

PRELIMINARY WATER CONTROL MANUAL

STRUCTURE 960 ·

DISCHARGE RATING CURVES

September 1991 USAEO Jacksonville

Plate A-960-1

4.0 4.0

Q:IOOO Q•IOOO

HW = 26.35 TW: 22.0

2.01

RIP.RAP

20 . 15 10 5

UPSTREAM

3 .. 5 3.5 c

3.0 ~ 3.0 u 1£.J

CJ)

0:

1£.J

2.5 a.. 2.5 t- 1£.J 1£.J

LL

2.0 >- 2.0 t--u ....J w

1.5 1.5

1.0 1.0

00.5 0.50

2.01

RIPRAP

5 10 15 20 25 30

DOWNSTREAM

Central and Southern Florida Project

UPPER ST. JOHNS RIVER BASIN

PRELIMINARY WATER CONTROL MANUAL

VELOCITY VS. RIPRAP

STRUCTURE 960

' i

I I _, September 1991 USAED Jacksonville

Plate A-960-2

6.0 r-· -·r · · t w w 2.0 ll...

iii _J w ~ I .0 ~.~44<~.....+ t- I w _J w I

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- .. ·r --,·-·-··· ~ . j ~-~;

···: i .. ·;

' '. ; . l

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60 70 80 90 100 200 300 400 500 6CO 800 1000 2000

DISCHARGE - CFS

DISCHARGE RATINGS BASED ON:

H Q=A j 2G 6.

Kenr + Kfr + Kexir

Kent= 0.50

Kfr = 29. ln 2

----X LENGTH

R4;3

Kexit = 1.0 n = 0.012 (CONCRETE,n =0.024 (CMP)

A = AREA OF PIPE (SQUARE FEET)

NOTE:

Kent 8 "n" VALUES FROM

TM5- 820-4 DATED JULY 1965

Central and Southern Florida Project

UPPER ST. JOHNS RIVER BASIN

PRELIMINARY WATER CONTROL MANUAL

SJRWMD CULVERT S-3

DISCHARGE RATING CURVES

Plate A-960-3

STRUCTURE 157 (S-157)

Location. S-157 is located in the Sebastian Canal (C-54) approximately 4.3 miles east of State Road 507.

Description. S-157 is an existing project spillway, designed and constructed under the 1962 plan of improvement. The structure is a three-bay U-shaped gated spillway, has an ogee weir with vertical lift gates and has a maximum design discharge of 6,500 cfs. Page A-157-2 contains the basic design data for S-157.

Purpose. The original purpose of S-157 was to hold the elevation of the Sebastian Canal (C-54) at elevation 15.5 ft., NGVD. Like S-96, S-157 was also designed to handle the diversion of flood waters from the Lake Wilmington Reservoir (also known as the Blue Cypress Marsh Conservation Area (BCMCA)) during large storm events. The design capacity of S-157 is 6,500 cfs under SPF conditions. Under the current plan, S-157 will serve as outlet for the release of flood waters from the St. Johns Water Management Area (SJWMA) through C-54 to the Atlantic Ocean. The Maximum Allowable Gate Opening Curves are found on Plate A-157-1. Discharge Rate Curves are found on Plate A-157-2.

Normal Regulation. The water surface elevation in C-54 is regulated at an optimum elevation 15.0 ft., NGVD insofar as possible. The gates of S-157 will be operated uniformly to pass up to the design discharge of 6,500 cfs or as much up to that amount that will reach the structure.

Flood Control. S-96, S-968, and S-258 provide sufficient capacity to discharge waters from the SJWMA to reduce the maximum stage and stage duration effects during storm conditions. The discharge through S-96 shall be proportionately reduced by the discharge through S-258 and S-968. When the stage in the SJWMA exceeds elevation 25.0 ft., NGVD, discharges may be made through S-96 not to exceed a discharge of 1500 cfs at S-157, and maximum possible discharge at S-96 and S-157 when SJWMA exceeds 25.5 ft., NGYD. As the SJWMA recedes, a discharge of 1500 cfs would be made at S-157 until the SJWMA reaches elevation 25.1 ft, NGVD. No regulatory discharge will be made at S-96 when the SJWMA falls below 25.0 ft., NGVD. Under SPF conditions an estimated 2,299 cfs could be released through S-96.

A-157-1

STRUCTURE 157

Location ----------------------------------------------- Design Conditions

Discharge (cfs) ------------------------------------ Headwater Elevation (ft.) -------------------------- Tailwater Elevation (ft.) ---------------------------

Optimum Condition Headwater Elevation (ft.) -------------------------- Tailwater Elevation (ft.) --------------------------

Maximum Headwater (ft.) ------------------------------- Crest

Shape ----------------------------------------------- Elevation (ft.)-------------------------------------- Net Length ------------------------------------------

Gates Number ---------------------------------------------- Width X Height (ft.) ------------------------------- Clearance Elevation ---------------------------------

Apron Elevation ------------------------------------------ Length ----------------------------------------------

Training Wall Elevation ------------------------------- Riprap

Length (ft.) ---------------------------------------- Elevation (ft.) ------------------------------------

Tieback Levee Elevation (ft.) --------------------------

A-157-2

C-54

6,500 15.5 3.9

15.0 -0.2 - 0.8

20.0

Ogee 7.5

50.0

25.0 x 12.5

16.5

-11.0 39.0 2.1

100.0 5.1

22.0

A,('.l "' "' ' I. "' .

I\.? 0 . ·_ ..

I/ /. L- , ·• I I i

110 R-&.>lj:'JC r10N.5 OIY G/tT£ CJ/?E,YllV6.S 8£LcHf/ /H/5,. LIN€

.12.u'-, ---'-------------------

0. 0 /,0 Z.o

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· s ·1s7

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..S-157

MAX. //LLOWABL£

&ATE OP£Al!AIG5 .3 :Sl'7Jt.~WAY (;.l;/eS oPcNGO l!Al)FOR;tiLY

3 GA 1/.;5 - 25.0 'W XIZ.S'H

Central and Southern Florida Project

UPPER ST. JOHNS RIVER BASIN

PRELIMINARY WATER CONTROL MANUAL

STRUCTURE 157

MAX. ALLOWABLE GATE OPENING CURVE

September 1991 USAED Jacksonvill

Plate A-157-1

~ 1. !.l Tv TH( '.1. fNt~ H

... ~ ..... f ( < :>' • ., 'J { ... '

UPPER ST. JOHNS RIVER BASIN

PRELIMINARY WATER CONTROL MANUAL

STRUCTURE 157

DISCHARGE RATING CURVES

STRUCTURE 161 (S-161)

Location. S-161 is located in L-73 approximately 1.5 miles south of U.S.

Highway 192.

Description. S-161 is an existing Corps of Engineers project spillway. The structure has an ogee spillway with vertical lift gates and a stilling basin to restrict velocities to nonerosive values. Page A-161-2 shows basic design data for S-161.

Purpose. Under the 1969 plan of improvement S-161 was to have been the main outlet for the Jane Green Reservoir by discharging into Jane Green Creek.

S-161 was to regulate the Jane Green Reservoir between elevations 42.0 and

46.0 ft., NGVD with a maximum design discharge of 2800 cfs when the headwater reached elevation 51.0 ft., NGVD. Under the current plan, S-161 will augment the discharges of·S-161A under large flood conditions. Plate A-161-1 contains the Discharge Rate Curve. ·

Normal Regulation. The Jane Green Detention Area water surface elevation will vary between elevations 19.0 and 22.0 ft., NGVD under normal daily conditions.

The structure operations will not significantly increase the stages currently experienced in the creeks and lowlands of Jane Green Swamp. S-161 and S-161A will not be operated except under flood conditions. The gates will be left opened and water will discharge freely over the weir during normal operating conditions. These structures will only be used to store water during flood events.

Flood Control. During Interim Plan 1 through the project completion S-161 will be operated as follows. S-161 and S-161A will be operated only under flood conditions. S-161A will serve as the main outlet of the detention area and is designed to reduce high river stages by holding floodwaters in the Jane Green Detention Area and making releases over a longer period of time. Flood storage is between elevations 22.0 and 41.3 ft., NGVD. The gates of S-161 and S-161A will be closed when the river stage at U.S. 192 is 19.5 ft., NGVD or greater. The flood waters will be held behind L-73 until the peak passes downstream. The spillway gate should be opened and closed gradually to provide an even transition to the new flow regime and minimize the hydraulic effect downstream.

A-161-1

STRUCTURE 161

Summarv of Hydraulic Design

Location ----------------------------------------------- Design Conditions

Discharge (cfs) ---------------------------------- Headwater Elevation (ft.) ------------------------ Tailwater Elevation (ft.) -------------------------

Optimum Condition Regulated Headwater Range (ft.) -------------------- Maximum Headwater (ft.) -----------------------------

Crest Shape ----------------------------------------------- Elevation (ft.)-------------------------------------- Net Length ------------------------------------------Gates · Number ---------------------------------------------- Width X Height (ft.) ------------------------------- Clearance Elevation ---------------------------------

Apron Elevation ------------------------------------------ Length ----------------------------------------------

Training Wall Elevation ------------------------------- Riprap

Length (ft.) --------------------------------------- Elevation (ft.) ------------------------------------

Protection Grade (ft.) --------~------------------------

A-161-2

L-73

2,000 45.0 26.0

42.0 - 46.0 51.0

Ogee 35.0 20.0

20.0 x 16.0

46.0

12.0 46.0 26.0

80.0 23.0 58.0

LLI

uJ I.&. ..

w ..J

UJ

a:

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O 4~ 600 12.00 1600 2000 1<400 t600 . lOOO

DI 5C~ARG.E., c.f.s.

S-IGI

Central and Southern Florida Project

UPPER ST. JOHNS RIVER BASIN

PRELIMINARY WATER CONTROL MANUAL

STRUCTURE 161

DISCHARGE RATING CURVES

ember 1991 USAED Jacksonville

Plate A-161-1

STRUCTURE 161A (S-161A)

Location. S-161A is located in L-73 approximately 1.5 miles south of U.S.

Highway 192. S-161A is situated next to existing structure S-161.

Description. The structure is a LI-shaped spillway, has an ogee weir, two vertical lift gates and a stilling basin to restrict velocities to nonerosive values. The design discharge is 8,465 cfs. The structure is sized to pass the design discharge with the gates full-open with concurrent design headwater and tailwater. Page A-161A-2 shows basic design data for S-161A.

Purpose. S-161A is designed to reduce high river stages by holding floodwaters behind L-73 in the Jane Green Detention Area and releasing water over a longer period of time. Discharges would be made as required to maintain design stages in the St. Johns flood plain downstream of the structure. The structure operation does not call for increasing the stages currently experienced in the creeks and lowlands of Jane Green Swamp. Low flow discharges will be passed by S-161A through two box culverts constructed in the sidewalls of the spillway. These culverts provide for the passage of flow at stages lower than the crest elevation and provide a means for complete drawdown. The structure is required to operate under hurricane alert conditions. The structure is sized to pass the design discharge with the gates full open and with concurrent design headwater and tailwater elevations.

Plate A-161A-l contains the Discharge Rate Curve. Velocity vs. Riprap curves are found on Plate A-161A-2.

Normal Regulation. The Jane Green Detention Area water surface elevation will vary between elevations 19.0 and 22.0 ft., NGVD under normal daily conditions.

The structure operations will not significantly increase the stages currently experienced in the creeks and lowlands of Jane Green Swamp. S-161 and S-161A will not be operated except under flood conditions. The gates will be left opened and water will discharge freely over the weir during normal operating conditions. These structures will only be used during flood events.

Flood Control. During Interim Plan I through the project completion S-161A will be operated as follows. S-161 and S-161A will be operated under flood conditions. S-161A will serve as the main outlet of the detention area and is designed to reduce high river stages by holding floodwaters in the Jane Green Detention Area and making releases over a longer period of time. Flood storage is between elevations 22.0 and 41.3 ft., NGVD. The gates of S-161 and S-161A will be closed when the river stage at U.S. 192 is 19.5 ft., NGVD or greater. The flood waters will be held behind L-73 until the peak passes downstream. The spillway gate should be opened and closed gradually to provide an even transition to the new flow regime and minimize the hydraulic effect downstream.

A-161A-l

STRUCTURE 161A

Location ---------------------------------------------- Station ------------------------------------------------ Design Conditions

Gate Design Discharge (cfs) ---------------------------------- Headwater Elevation (ft.) ------------------------ Tailwater Elevation (ft.) -------------------------

Stilling Basin Design Discharge (cfs) ------------------------------------ Headwater Elevation {ft.) -------------------------- Tailwater {ft.) -------------------------------------

S.P.F. Condition Discharge {cfs) ------------------------------------

. Headwater Elevation {ft.) -------------------------- Tailwater Elevation (ft.) --------------------------

Optimum Condition Headwater Elevation (ft.) -------------------------- Tailwater Elevation {ft.) ---------------------------

Crest Shape ----------------------------------------------- Elevation (ft.)-------------------------------------- Design Head {ft.) ----------------------------------- Net Length ------------------------------------------

Gates Number ---------------------------------------------- Width X Height (ft.) ------------------------------- Clearance Elevation -~------------------------------ Overflow Slot Elevation -----------------------------

Instrumentation Headwater Recorder·and Staff Gage ------------------ Tailwater Recorder and Staff Gage ------------------ Gate Position Recorders -----------------------------

Stilling Basin Elevation ------------------------------------------ Length ---------------------------------------------- Endsill Elevation ---------------------------------- Baffle Block Elevation ----------------------------- Rows of Baffle Blocks -------------------------------

Training Wall Elevation --------------------------------

A-161A-2

L-73 839+00

8,465 41.3 26.0