The Determination of Minimum Flows for Sulphur Springs, Tampa

DRAFT
The effects of tide stage on salinity could be used to minimize salinity incursions while
allowing for diversions of water from the spring pool. For example, flows could be
reduced from 18 cfs to 10 cfs during times of low river levels (< -0.5 feet) without
causing the incursions into the spring run. In this regard, a plan to manage flow from the
spring that accounted for tide stage in the river could make additional spring water
available for use without causing significant salinity incursions. It is not known how
quickly the hydraulic relationships at the weir would respond to such changes in flows,
and the most effective manipulation of flows based on water levels would require further
field testing.
5.2.5 Relations of springflow to water levels in the upper spring run
In addition to their effect on salinity, changes in flows could affect the water levels in the
spring run and the depth and inundation characteristics of aquatic habitats. As
previously discussed, water levels in the run largely track water levels in the river at high
tide stages. As a result, the water levels in the run that occur at medium or high tides do
not show a strong relationship with flow. Daily mean and maximum water levels are
plotted versus same-day springflow in Figures 5.9 a and b. There is no apparent
response of maximum daily stage with flow, and a simple linear regression between
these variables was not significant (p