Southwest Aggregates Reservoir Project Summary of Presentation - - PowerPoint PPT Presentation

Summary of Presentation

• Overview of conditions in

Babcock Webb

• Review of Conditions in

Yucca Pens

• Regional Storage and

Conveyance Opportunities

• Bond Farm –
• Store excess water from Babcock Webb
• Stored water reserved for Yucca Pens
• SW Aggregates –
• Cape Coral supplemental water supply
• Pathway from Bond Farm to U.S. 41

Southwest Aggregates Reservoir Project

Babcock Webb Hydroperiod

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CH CH-NCRB_091 9181 816 Bond Fa Farm

• SW Babcock Webb

has too much water

• Optimum hydroperiod

is 4 months

• Extensive year-round

flooding of wetlands and uplands

• Well-documented

vegetative impacts

• Water levels are elevated in the wet season
• Hydroperiods are longer than appropriate
• Strong consensus on excessive water conditions

Babcock Webb Water Levels / Hydroperiod

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BondFarm_ExistingConditionsModel_071719_LT

• 2.0
• 1.5
• 1.0
• 0.5

0.0 0.5 1.0 1.5 2.0 2.5 1/1/08 12/31/08 12/31/09 12/31/10 12/31/11 12/30/12 12/30/13 12/30/14 12/30/15

Water Depth, ft Simulated Water Depth at Edge of Tree Island in SW Babcock Webb

Depth relative to ground Ground Level

Yucca Pens Hydroperiod Needs

• Yucca Pens hydrology generally adequate in wet season
• Staff gage data suggests that wetlands in portions of Yucca Pens may

have shortened hydroperiods

• ATV channel blocks installed in 2013 improved hydrology in south Yucca

Pens, but drainage problems remain close to Gator Slough

• Hydroperiods in cypress swamps may be adequate, but vegetation

indicators and concentrated flow patterns in remnant ATV trails suggest some remaining challenges

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Estimate of Extent of Yucca Pens Wetlands that May Need Water

• FWC Wetland area ≈ 6000 acres
• Objective is to extend hydroperiod

by 1 – 2 months

• Water need is approximately one

foot to extend wet season

• Water need is ≈ 6,000 acre-feet
• Bond Reservoir meets 40% of

estimated Yucca Pens need

• Improvements needed for

hydrologic restoration:

▪ Additional storage ▪ Conveyance to Yucca Pens ▪ Additional channel blocks

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• Blue areas have too

much water

• Yellow-red areas do

not have enough water

Summary of Hydroperiods in Babcock Webb and Yucca Pens

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• Bond Water Storage Facility is 600 acres, max depth = 4 feet for 2,400 ac-ft capacity
• SW Agg Reservoir is 500 acres, max range of depth = 10 feet for 5,000 ac-ft capacity
• Water pumped into both storage facilities during wet season
• Water released from Bond to Yucca Pens at end of wet season

▪ Generally starting in December for one or two months

• Water is released from SW Aggregates Reservoir to the City of Cape Coral

▪ Generally starting in March for two to three months ▪ Maintain pressure in reuse lines for irrigation and fire protection to 30% of CC fire hydrants

Analysis of Bond Water Storage Facility and Southwest Aggregates Reservoir Improvements

Scenario Assumptions for Modeling Analysis

• Model simulation conducted from 2007 through 2015
• Water pumped into both reservoirs during wet season and released in dry season
• Simulated water delivered from Babcock Webb to reservoirs was 8,200 ac-ft/yr
• Water deliveries only during wet season when water levels above set threshold

Estimate of Long-term Available Yield from Babcock Webb WMA

2,000 4,000 6,000 8,000 10,000 12,000 14,000 2007 2008 2009 2010 2011 2012 2013 2014 2015

Acre-feet/Year

Flows Delivered to Bond Farm and Southwest Aggregates

Benefits of Southwest Aggregates Reservoir on Babcock Webb WMA

• Water depth reductions of up to one

foot in areas of with excessive water

• Remaining areas of standing water

consistent with mapped wetlands

• Remaining wetland water depths

range from 0.5 to 3 feet

▪ Optimum wet season water depths should be 1 to 2 feet (Duever)

• More than enough water in Babcock

Webb to fill both reservoirs annually

• More water storage needed to restore
• ptimum hydroperiods

Estimate of Water Available for Yucca Pens

• Estimated excess water available in

Babcock Webb 15,000 ac-ft/yr

• Bond provides 2,400 ac-ft/yr
• SW Agg provides 4,600 ac-ft/yr
• Remaining excess is 8,000 ac-ft/yr
• Yucca needs 6,000 ac-ft/yr

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Summary and Conclusions

• Excess water in Babcock Webb WMA

currently creating ecological damage

• Inadequate water in Yucca Pens
• Bond Farm provides some storage

but lacks conveyance to YP

• SW Aggregates Reservoir provides

▪ Needed water supply growing city ▪ Additional storage for excess water ▪ Potential conveyance to Yucca Pens

• Excess water remaining in Babcock

Webb WMA with reservoir project

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