influence of groundwater flows on wetland restoration project at juniper bay swamy pati bio. &...
TRANSCRIPT
![Page 1: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/1.jpg)
Influence of Groundwater Influence of Groundwater flows on Wetland Restoration flows on Wetland Restoration
Project at Juniper BayProject at Juniper Bay
Swamy Pati
Bio. & Ag. Engineering Dept., NCSU
SSC 570 - Wetland Soils
Term Paper Presentation
![Page 2: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/2.jpg)
Outline
• Introduction
• Carolina Bays
• Wetland Restoration Requirements
• Project Objectives
• Methodology
![Page 3: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/3.jpg)
Introduction
• Research project – Assessment of Groundwater flows at Juniper Bay and their impacts on the surrounding area.
• This project is a supplement to the wetland restoration project underway at Juniper Bay.
• Project mainly focuses on the influence of the subsurface flows on wetland restoration.
• Juniper Bay is one of the Carolina Bays, which are spread throughout the Southeastern Coastal plain of US.
![Page 4: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/4.jpg)
Literature review – Origin of Carolina Bays
• Carolina Bays are small orientated depressions, elliptical to ovate in shape, that the south-eastern coastal plain of the united states in incredible density and range.
• Extend from the Delmarva Peninsula in north to the Okefenokee swamp in Northern Florida.
![Page 5: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/5.jpg)
Arial Photograph
![Page 6: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/6.jpg)
Origin of Carolina Bays
• D.W. Johnson, 1936 – shape and orientation, as well as presence of sandy rims are attributed to wind and wave action and depressions are attributed to the artesian process.
• W.F. Prouty, 1952 – comet or asteroidal body entering the earth atmosphere at an oblique angle from a relatively northwesterly direction.
• Bruce G. Thom, 1970 – Humate allows for a perched water table near the surface that would eventually evolve into shallow, wet depressions, orientated later by wind and wave action.
![Page 7: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/7.jpg)
Origin of Carolina Bays
• J. Ronald Eyton & Judith I. Parkhurst, 1975 – considered the theory stated by Prouty, 1952 and then they stated finally that comets are the cause for the creation of Carolina Bays.
• Raymond T. Kaczorowski, 1977 – ruled out the extraterrestrial theory as a cause for Bay formation and supported Thom’s water table perching theory. He suggested that the only requirement for Bay existence is poor drainage leading to ponding mechanisms.
• Reference: http://bss.sfsu.edu/jdavis/geog810/1999/black.html
![Page 8: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/8.jpg)
Hydrology of Carolina Bays
• The hydrology of Carolina Bays is influenced by subsurface flows inputs and fine textured soil or parent material layers that restrict the downward movement of stored water in the Bay.
• Studies on the complex hydrology of Carolina Bays have shown complex subsurface interaction with the surrounding area
• Local depressional hydrology superimposed on the regional subsurface hydraulic gradients of the landscape in which the bay occurred.
![Page 9: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/9.jpg)
Wetland restoration Requirements
• Wetland restoration projects needs assessment of the site in all factors to meet the restoration goals set by the US Army Corps of Engineers.
• Wetlands hydrology, hydric soils, and plant community similar to the reference ecosystem be restored.
• Site assessment, identification of potential functions, methodologies to restore wetland functions, and effective assessment of progress of functional restoration.
![Page 10: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/10.jpg)
Hydrologic aspects of Wetland Restoration
• Ditching and pumping in the surrounding area of the site
• Regional subsurface hydraulic gradients • Filling the ditches is not suffice• Regional hydrology must be assessed and
restoration methods must account for restoration of historical regional surface and subsurface hydraulic gradients.
![Page 11: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/11.jpg)
Juniper Bay
![Page 12: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/12.jpg)
Groundwater flows at Juniper Bay
• Lateral Groundwater Flows
• Preliminary work suggests non-negligible gradients across JB boundary
• Core data suggest an effective bottom to the surficial system – Black Creek Confining Unit
• Current well/piezometer network insufficient to assess lateral flows
![Page 13: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/13.jpg)
Stratigraphy
![Page 14: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/14.jpg)
Importance of Perimeter Ditch
• Lateral boundary of the project is the perimeter ditch.• It influences the flows in the surficial aquifer and
prevents the flows between interior and exterior of the bay.
• It can effectively drain 100 feet to either side. • Influence of the perimeter ditch through the partially
confined sand layers underlying the surficial aquifer is one of the main trusts of the project.
![Page 15: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/15.jpg)
Objectives
• Characterize the subsurface flows at four locations on the perimeter
• Interaction of the perimeter ditch
• Model the subsurface flows
• Develop the management recommendations.
![Page 16: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/16.jpg)
Characterize the subsurface flows
• Four locations are selected around the perimeter of the project site.
• Coring work was started in these locations.
• Coring is being done at 5 points at each transect.
• These are the same points at which nests of piezometers will be installed.
![Page 17: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/17.jpg)
North-facing view of the Juniper Bay
![Page 18: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/18.jpg)
Locations of Piezometer Transects
![Page 19: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/19.jpg)
Transect of Piezometer Nests
![Page 20: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/20.jpg)
NW - Transect
![Page 21: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/21.jpg)
SE - Transect
![Page 22: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/22.jpg)
SW - Transect
![Page 23: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/23.jpg)
NE - Transect
![Page 24: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/24.jpg)
Characterize the subsurface flows
• With the cores collected at different locations saturated hydraulic conductivity tests are conducted and values are estimated.
• Then flows crossing site boundaries will be calculated.
![Page 25: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/25.jpg)
Ksat tableDescribed By: A. Adams Core Diameter (cm) 7.62Ksat Test By: Swamy PatiCore Location: NW-IN-75 Core Height (cm) 7
Horizon DEPTH (ft) COLOR TEXTURE CORE # COMMENTS time, min Q, ml H20 ht, cm Ksat, cm/min0 - 0.5 10YR2/1 SL 18 diffuse or gradual boundary
0.5 - 1.17 10YR6/1 S/SL 1013 diffuse or gradual boundary 1 13 6.1 0.07371.17 - 2.5 10YR4/2 C 1000 1.33 15 5.5 0.0612.5 - 3.1 10YR 4/3 SCL 1077 all roots or wood 1.5 5 5.8 0.0183.1 - 3.67 10YR5/2 & 10YR5/3 SCL 86R seems to be transition zone 6.2
3.67 - 540% 10YR5/2 & 60%
10YR6/2 C w/ SCL 1083 packets of SCL, at bottom all SCL 2.33 14 6 0.033
5 - 5.8390% 2.5Y6/2 & 10%
10YR2/1 SC 1102 black at top 5.95.83 - 7.58 2.5Y6/2 SCL 1109 reduced Fe++ througout 5.87.58 - 8.58 2.5Y6/2 SL 28R varying sand content 1440 15 5 5.25E-058.58 - 9.5 2.5Y7/2 LS 1119 Fe oxidized throughout 55 15 4.2 0.00139.5 - 10.1 2.5Y6/2 SL 51 Fe oxidized throughout 9.66 9 5.4 0.01
10.1 - 10.58 2.5Y8/1 S 1016 Fe oxidized throughout 5.510.58 - 11.58 2.5Y6/1 CL 1126 Fe oxidized throughout 5.511.58 - 13.25 2.5Y6/2 SL 1024 Fe oxidized throughout 2.1 50 6 0.134
13.25 - 15 2.5Y4/1 SCL 182R Fe oxidized throughout 33.83 11 4.5 0.001615 - 16.58 2.5Y3/1 SCL 1055 Fe oxidized throughout 1.67 60 5.5 0.196
16.58 - 18.67 2.5Y3/2 & 6/2 LS/S 20R(top) Fe oxidized throughout 1 15 5 0.0814R (bottom) 2.58 35 4.4 0.067
18.67 - 19.83 2.5Y3/1 SL 119R Fe oxidized throughout 3 9 5.2 0.01619.83 - 21.25 2.5Y3/1 SL 1044 Fe oxidized throughout 1 24 4.7 0.12321.25 - 22.25 N4 C 10-R Fe oxidized throughout 4.922.25 - 22.5 2.5Y3/1 SL not enough for sample22.5 - 24.83 2.5Y3/1 C 988 top same as 21'5'' - 22'5''' 6 9 4.4 0.007
51-R bottom 524.83 - 29.83 2.5Y3/1 C 1041 top material contained from section above Fe is oxidized
1079 middle 3 16 5.2 0.01061087 bottom 4.2
29.83 - 34.83 2.5Y3/1 C 1106 top same as 25' - 30' 41078 middle 5.81043 bottom 5.5
34.83 - 37.33 2.5Y3/1 C 1037 top white sand grains throughout but very very firm1083 bottom 600 10 5.8 0.000094
37.33 - 39.83 10YR3/1 C 70R top white sand grains throughout in 5% of matrix1063 bottom contains some packets of sand
39.83 - 42.33 10YR3/1 C 30-H4 top sand samples are present in same percentages, soil is brittle1045 bottom
![Page 26: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/26.jpg)
Piezometers• Piezometers are installed at these locations at all
significant sand layer at each point on the transect.
• Hydraulic heads will be monitored in the piezometers and perimeter ditch.
• Instrumentation is installed with all the piezometers to monitoring the water levels.
• Hydraulic gradients, Hydraulic conductivities, lateral and vertical fluxes will be estimated
![Page 27: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/27.jpg)
Future Work - Additional Field Work
• Perimeter cores (8-12) for stratigraphic data
• Ground-penetrating radar surveys
![Page 28: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/28.jpg)
Additional Coring
![Page 29: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/29.jpg)
Role of the Perimeter Ditch
• How deeply does the perimeter ditch influence subsurface flows?
• Could/should it be preserved to control boundary flows? What management scheme?
• Elimination of the perimeter ditch could increase wetland area by 30-100 acres.
![Page 30: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/30.jpg)
Groundwater Modeling
• There are various different kinds of modeling software available to model groundwater.
• Some of them are CFEST, MIGRATE, DYNFLOW, MODFLOW, etc.
• Except MODFLOW most of the other groundwater flow models are used to simulate the solute or chemical transport phenomena.
• In this project we are mainly dealing with the hydraulic aspects of the groundwater flow, MODFLOW will be appropriate to use.
![Page 31: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/31.jpg)
MODFLOW
• Input parameters: Aquifer parameters, hydraulic parameters, dimensionality, initial conditions boundary conditions.
• Some of the input parameters will be estimated from the field data.
![Page 32: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/32.jpg)
MODFLOW
• MODFLOW simulates hydraulic head and velocity field distribution and they solve the groundwater flow equation.
• This model can handle multiple layer porous media, with either confined, unconfined or semiconfined. Heterogeneous, anisotropic or compressible porous media can also be modelled.
• Finite difference solution technique is used in this model.
![Page 33: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/33.jpg)
MODFLOW
![Page 34: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/34.jpg)
MODFLOW
• Number of layers and the input parameters change depending on the scenario the model is run for.
![Page 35: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/35.jpg)
Modeling
• Using the model we predict the flows in the surficial aquifer for the entire site
• Model will be run for different management scenarios – w/ & w/o the perimeter ditch
• Predict the impacts of the conversion on the water table levels in adjacent properties
![Page 36: Influence of Groundwater flows on Wetland Restoration Project at Juniper Bay Swamy Pati Bio. & Ag. Engineering Dept., NCSU SSC 570 - Wetland Soils Term](https://reader036.vdocuments.us/reader036/viewer/2022062300/56649d055503460f949d86f6/html5/thumbnails/36.jpg)
THANK YOU
Questions?