Download presentation
Presentation is loading. Please wait.
Published byTrevon Claywell Modified over 9 years ago
1
OVERVIEW OF SUSPENDED SOLIDS TRANSPORT AND LIVING RESOURCE INTERACTIONS Ross Mandel Interstate Commission on the Potomac River Basin March 8, 2004
2
SSTLR U. S. Army Corps of Engineers, Baltimore District Metropolitan Council of Governments Carl Cerco Engineering Research Development Center Supported by D. C. Department of Health Maryland Department of the Environment Chesapeake Bay Program
3
GOALS OF SSTLR Improve Representation of Suspended Sediment Better Simulation of Relation Between Suspended Sediment and Living Resources (Algae, SAV) Specific Improvements to Eutrophication Model in the Potomac
4
JANUARY 6, 2004 CBP MODELING SUBCOMMITTEE MEETING http://www.chesapeakebay.net/calendar.cfm
5
TOPICS Refined Modeling Grid Bank Loads Resuspension and Settling of Sediments Light Attenuation Phosphorus Dynamics pH—Alkalinity—Sediment P Release Algal Speciation
6
REFINED MODELING GRID Improve representation of shoreline processes Represent DC, MD, and VA waterbodies on 303(d)Lists (including Anacostia River) Sung-Chan Kim (ERDC) Sung-Chan.Kim@erdc.usace.army.mil
8
BANK LOADS
9
BANK LOADS--CURRENT MODEL Cerco and Noel (2003): http://www.chesapeakebay.net/modsc.htm
10
BANK LOADS--SSTLR Simulate bank erosion by wave action New bank erosion surveys in MD, VA Photo borrowed from Halka and Hennessee (MSC 1/6/04)
11
SEDIMENT RESUSPENSION CURRENT MODEL Resuspension not represented as a physical process Net Settling: Settling – Resuspension Net Settling Rates 5-10% of Actual Settling Velocity
12
RESUSPENSION RESEARCH—SSTLR FOUR AXIAL SURVEYS OF POTOMAC Larry Sanford (UMCES) Carl Friedrichs (VIMS) Jerome Maa (VIMS) Joe Gailani (ERCD)
13
SURVEY SITES from Sandford et al. MSC 1/6/04
14
PARTICLE SETTLING—SSTLR PHYTOPLANKTON-SEDIMENT INTERACTIONS Michael Kemp and Walter Boynton (UMCES) Diatom-Clay Aggregate Hamm (2002) via Kemp and Boynton MSC 1/6/04
15
LIGHT ATTENTUATION CURRENT MODEL a1 to a5 = empirical constants ISS = inorganic suspended solids concentration (g m-3) VSS = organic suspended solids concentration (g m-3) DOC = dissolved organic carbon (g C m-3) Chl = chlorophyll (mg m-3) Cerco and Noel (2003)
16
LIGHT ATTENTUATION—SSTLR Charles Gallegos (Smithsonian) Reformulate Representation of Light Extinction in terms of Inherent Optical Properties (Absorption and Scattering) Field measurements of spectral backscattering, total scattering, and absorption Laboratory measurements of absorption components
17
PHOSPHORUS CYCLE—CURRENT MODEL Cerco,MSC 1/6/04
18
PHOSPHORUS CYCLE—SSTLR Jeff Cornwell (UMCES) and Vic Bierman (Limno-Tech) Cornwell, MSC 1/6/04
19
PHOSPHORUS CYCLE—SSTLR Add Particulate Inorganic Phosphorus to Model Determine Bio-availability of P Species Field Work in Potomac: Characterize Spatial/Temporal Distribution of P Species Laboratory Work: Determine P Sorption
20
pH-ALKALINITY-PHOSPHORUS DYNAMICS James Fitzpatrick (Hydroqual) Vic Bierman and Joe DePinto (Lino-Tech) Smith Point, September 2003 Bierman, MSC 1/6/04
21
1983 ALGAL BLOOM 1970’s: Phosphorus Controls Installed at Blue Plains and Elsewhere to Control Algal Blooms 1983: High Spring Flows, Low Summer Flows, Below Normal Wind Speeds, Higher Temperatures July –November :Microcycstis Bloom From Piscataway Creek to Indian Head, Maximum Concentrations > 200ug/L pH Rises from 7 to 9-10 in Vicinity of Bloom
22
MECHANISM Modeled in Revised Potomac Eutrophication Model (PEM) Post-1983 Uptake of Inorganic Carbon By Algae Raises pH High pH ( 9-10) Causes Dramatic Increase in P Released From Sediments Increased P Concentration Increases Algal Growth
23
PHOSPHORUS SORPTION DYNAMICS Hydroqual, (MWCOG 1989)
24
pH—P SORPTION RELATION Hydroqual, (MWCOG 1989)
25
pH-ALKALINITY MODEL--SSTLR Put pH P Release Dynamics from PEM in Current Sediment Nutrient Flux Model New State Variables and Dynamics to Represent pH, Alkalinity, and Calcium in Water Column
26
ALGAL SPECIATION Vic Bierman (Limno-Tech) and Chris Jones (GMU) Improve representation of sources, succession, food-web dynamics Improve representation of spring diatom bloom Improve representation of Microcystis dynamics
27
ICPRB SUPPORTED ACTIVITIES FUNDED BY EPA REGION III 104(B) GRANT Field Characterization of Sediment P and Laboratory Analysis of pH-Mediated Sediment P Release ( Boynton and Cornwell, UMCES) Collection and Analysis of pH-Alkalinity Data for Potomac Estuary Review Connection Between Algal Speciation, Chlorophyll Criteria, and Higher Trophic Levels
28
SCHEDULE COMPLETION DATE: 2007
29
CONTACT INFO Ross Mandel Interstate Commission on the Potomac River Basin rmandel@icprb.org
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.