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Section 5 Formulation of Alternative Plans

EAA Storage Reservoirs Revised Draft PIR and EIS February 2006

5-10

reservoirs) and because a marsh habitat would have to be kept hydrated, the

evapotranspiration loss would be much higher than for reservoirs, thereby

significantly reducing the storage value of these areas. A long, rectangular

configuration would have a 75% longer levee than a traditional storage reservoir,

thus increasing environmental impacts, project cost, and the area devoted to

seepage management features. Because nutrient-laden soil would be flooded for

the flow-way, the vegetation most likely to dominate would be cattails and other

invasive exotics that would degrade the Everglades habitat.

Flow-ways would not “hold back” water going to the WCAs and the delivery of

that water would exacerbate the already high stages in the northern parts of the

WCAs. Thus, the timing of flows from flow-ways would not be manageable or

beneficial for the remaining Everglades. Perhaps the most crucial element,

water flowing from the lake to the WCAs is not present in dry or even normal

years. For example, during long periods (e.g., from 1970-1982 and 1985-1994 in

the hydrologic modeling period of record), no significant excess lake water would

be available for delivery to the flow-way. Only demand releases to the

Everglades were made from the lake during those periods. Water delivered to

the Everglades on a demand basis, through a flow-way, would not be efficient

due to increased travel times and increased evapotranspiration losses. The only

years in the period of record where water could flow through the flow-way for

long durations were wet periods like 1969-1970, 1982-1983, and 1994-1995. In

those years, the stages in the WCAs were already too high and additional flow

from flow-ways would have been damaging, not beneficial. Perhaps the most

important reason why flow-ways were not included in the Comprehensive Plan

was because of the significant water losses that would be unacceptable in an

ecosystem in which dry season performance was already impacted. Flow-ways

would place an additional hydrological demand on the system.

5.2.1.6 Storage South of Lake Okeechobee in the EAA

Creating above-ground reservoirs south of Lake Okeechobee in the EAA could

meet all the planning objectives:

1. Improve the timing of environmental deliveries of water to the WCAs,

2. Reduce regulatory releases of water from the EAA to the WCAs,

3. Reduce regulatory releases of water from Lake Okeechobee to the St.

Lucie and Caloosahatchee estuaries,

4. Meet agricultural demands within the EAA, and,

5. Increase flood protection within the EAA.

This option would avoid pumping water through Lake Okeechobee with its

attendant treatment requirements. It has the advantage of robust hydraulic

connections with both the lake and the EAA through the existing canals. It also

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