the floridan aquifer chipola river system study l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
The Floridan Aquifer/Chipola River System Study PowerPoint Presentation
Download Presentation
The Floridan Aquifer/Chipola River System Study

Loading in 2 Seconds...

play fullscreen
1 / 31

The Floridan Aquifer/Chipola River System Study - PowerPoint PPT Presentation


  • 233 Views
  • Uploaded on

The Floridan Aquifer/Chipola River System Study. Funded by: U.S. Geological Survey National Water Quality Assessment Program (NAWQA) and Florida Department of Environmental Protection (FDEP). Christy Crandall U.S. Geological Survey Tallahassee, Florida 850 942-9500 ext. 3030

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'The Floridan Aquifer/Chipola River System Study' - jaden


Download Now An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
the floridan aquifer chipola river system study

The Floridan Aquifer/Chipola River System Study

Funded by: U.S. Geological Survey

National Water Quality Assessment Program (NAWQA)

and

Florida Department of Environmental Protection (FDEP)

Christy Crandall

U.S. Geological Survey

Tallahassee, Florida

850 942-9500 ext. 3030

crandall@usgs.gov

study objectives
STUDY OBJECTIVES
  • Identify significant sources of nutrients to the Floridan aquifer system in the lower ACF basin and in the Chipola River basin.
  • Characterize hydrologic and transport processes occurring along flowpaths from areas contributing recharge to discharge points of interest using a ground-water flow and particle tracking model.
  • Use flow and tracking model to match nitrate concentrations in ground water from areas contributing recharge to 6 NAWQA trend wells, Jackson Blue Spring, Baltzell spring group, and Sandbag Spring—springs that flow into the Chipola River.
  • Use the ground-water flow and tracking model to test hypothetical scenarios changing management practices in using the flow and tracking model.
contaminant occurrence in the upper floridan aquifer and recharging rivers
Contaminant occurrence in the Upper Floridan aquifer and recharging Rivers

Purpose of study is to determine:

Factors affecting nitrate occurrence and distribution in the Upper Floridan aquifer in the Dougherty Karst Plain

  • Distribution of travel times from recharge to discharge
  • Land use effects on nitrate concentrations
  • Transport processes in ground water
  • Effects of Withdrawals on flowpaths and travel times
floridan aquifer system
Vertically contiguous sequence of limestone and dolostone of late Paleocene to early Miocene age ranging from 0 to 1250 feet thick in the study area

Sand overlying clay and limestone

Clay lenses in places between the sand and Limestone

Highly potable

Contains numerous springs, sinks and other karst features—highly vulnerable.

Floridan Aquifer System
slide6

Extent of Floridan

Topography

of the

Dougherty

Karst Plain

floridan aquifer system in the dougherty karst plain
Floridan Aquifer System in the Dougherty Karst Plain
  • High rates of direct recharge through sinkholes and indirect recharge through overburden—mostly sand and silty sand
  • High rates of discharge to large incised streams through springs.
slide10

Northern Extent of

Floridan Aquifer System

  • Confinement--Recharge occurs mainly in unconfined and semi-confined areas
  • Potentiometric surface—flows southward to rivers from northern extent
slide11

Ground water makes up the majority of discharge during low-flow conditions in the Dougherty Karst Plain.

  • For example at least 63 springs identified and sampled along the Chipola River.
  • (Barrios and Chellette, 2004)
existing models 2006
Existing Models 2006

Models from Elliott Jones and Lynn Torak 1996 and 2006

  • MODFE Finite element transient 2-D model developed to simulate the effects of 4000 irrigation wells on baseflowconditiotns in the Flint river.
slide13

Current MODFLOW

Active Model-Grid Boundary

Tallahassee

Jones and Torak

MODFE Model

Boundaries

comparison of model features
Comparison of Model Features

MODFE Developed to simulate the effects of irrigation on the Flint/Apalachicola Rivers baseflow

MODFLOWDeveloped to simulate nitrate tracking and concentrations recharging rivers

Steady State

Uniform cell-size (1000 m)

2 layer surficial/residuum, UFA fully 3-D model

Over 4000 Wells simulated

  • Steady State (Torak and others, 1996) and then 1-year transient (1999-2000) (Jones and Torak, 2006)
  • Variable Element Size
  • 1 layer 2-D model
  • 4000 Wells simulated
slide15
MODLFOW model derived the following starting parameters where available

from Torak and Jones

  • Hydraulic parameters
  • Aquifer tops and bottoms
  • Pumping data
  • Recharge
  • Boundary conditions
  • River and drain stage and conductance
  • Starting heads
model calibration data
Model Calibration Data
  • 329 head observations in the Floridan aquifer
  • 65 flow observations including perennial and non-perennial streams
modflow budget components flow in cfs
MODFLOW Budget Components  Flow in CFS
  • CONSTANT HEAD 3,397
  • WELLS = 0.00
  • NONPERENNIALS = 0.00
  • PERENNIALS = 253
  • HEAD DEP 5332
  • RECHARGE = 1,909      
  • TOTAL IN 10,890      
  • CONSTANTHEAD2,772
  • WELLS=810
  • NONPERENNIALS=188
  • PERENNIALS = 3124
  • HEADDEP3,996
  • RECHARGE=0.00
  • TOTALOUT10,890
regional model
Regional Model
  • UFA broken into 3 layers
  • Local Grid Refinement in areas of interest
  • Karst Features added throughout—
    • Sinkhole
    • Conduit layer
local grid refinement28
Local Grid Refinement
  • 12 layers—
    • 3 in the surficial
    • 9 in the Floridan

Improves flow path accuracy and travel time estimates

Better areas contributing recharge definition

summary
Summary
  • Add local grids at Balztell and Sandbag Spring Group as well
  • Finalize nitrate travel time estimates and area contributing recharge with these models
  • Finish report