Figure 32. Map of Conservation 

 Area 3 and control 

 structures (adapted 

 from SFWMD 1977). 



redistributed by Tamiami Canal 

 southward through numerous stub 

 canals into Everglades National Park 

 (ENP) and the East Everglades 

 (Parker et al. 1955). When levees 

 29 and 67A were constructed in 1962 

 and 1963 the pattern and magnitudes 

 of flow delivered to ENP on the 

 south changed dramatically (Leach 

 et al. 1972). Figure 32 outlines 

 the structures and flow patterns 

 involved in the transmission of 

 waters through the Tamiami Canal 

 south to ENP and the East Ever- 

 glades. Flow patterns across the 

 canal are divided into 3 sections, 

 the western section from Monroe to 

 40-mile bend, the middle section 

 from 40-mile bend to L-67A, and the 

 eastern section between L67A and 

 L-30. 



In the westernmost section 

 beyond Conservation Area 3, Leach 

 et al. (1972) found that flow con- 

 tinued in much the same pattern 

 after levee construction as prior to 

 construction. In the middle section 

 flow was routed through four spill- 

 ways (S-12, A-D) and down the Levee 

 67A extension canal, while in the 

 easternmost section flow was re- 

 stricted to seepage across and under 

 levee L-29. Prior to construction 

 of L-29 the eastern section provided 

 considerably more water to the south 

 Dade, East Everglades area than it 

 does today. Peak flows to the south 

 were highest in the eastern section 

 before levee 67-A directed water to 

 the middle section and levee 29 

 acted to retain most of the water 

 within Conservation Area 3B. In the 

 middle section peak flows have been 

 augmented due to storage and diver- 

 sion. In summary. Leach et al. 

 (1972) identify two major changes 

 that have occurred in terms of water 

 input to lower Shark River Slough 

 over the past 40 years: 



(1) A general increase in the 

 flow of water to the Evei — 

 glades resulting from the 

 deflection of water south by 

 levee 30 along the coastal 

 ridge; and 



(2) redistribution of the major- 

 ity of flow through the 

 spillways below area 3A away 

 from the East Everglades due 

 to construction of levee 

 67-A and levee 29. 



Because hydroperiod plays such 

 as important role in the ecology of 

 the Everglades, considerable atten- 

 tion has been fixed on determining a 

 minimum water input requirement for 

 Everglades National Park. This in- 

 put is to be delivered and regulated 

 by SFWMD, the regional water man- 

 agement agency. Dealing strictly 

 with the runoff component of this 

 input, Leopold et al. (1969) estima- 

 ted an annual minimum requirement of 



74 



