technical memoranda

  • Practitioners
  • Research
  • Academia
  • Geology
  • Marion County Hydro

PONDS Software – Technical Notes & Procedures

- How a dry pond is considered in Nutrient Loading calculations for SJRWMD Permitting.
How a dry pond is considered in Nutrient Loading calculations for SJRWMD Permitting.
- How to compute nutrient removal in chained wet ponds.
The combination of two wet ponds in series is not directly addressed in the currently proposed methodology (Harper method) for calculating the nutrient removal of a wet pond. When analyzing two wet ponds in series (as depicted in Exhibit 1 below) we suggest that the two wet ponds should instead be considered as a single wet pond, and the residence time of the combined ponds should be calculated using the combined (permanent pool) volumes.
- Modeling Contiguous Ponds With Shared Borders.
One way to model this is to assume that the shared perimeter becomes a no flow boundary, and that no horizontal flow can occur through that boundary. This reduces the length of perimeter which is available for saturated horizontal infiltration, so the “effective” (i.e., non-shared) perimeter should be used for modeling. An effective pond length and width are then chosen which will generate the same length of effective perimeter.
- Modeling an exfiltration trench using Refined Method Module.
In PONDS 3.2, an exfiltration trench is modeled using the Refined Method module. Conceptually, an exfiltration trench is modeled as if it were a pond with one major exception.
- Adjusting Geometry Parameters (etc) for an Exfiltration Trench.
The following memo outlines some details that may need to be considered when modeling an exfiltration trench (i.e., French drain, etc.) using the PONDS 3.2 Refined Method.
- How to model baseflow using the Refined Method Module.
how to compute baseflow using the PONDS 3 .2 Refined Method.
- Retaining Walls Around Ponds.
How to modify the horizontal hydraulic conductivity value to model the effect of a partially penetrating or completely penetrating retaining wall/clay core around a retention pond.
- Analyzing PONDS With Sand Chimneys.
In some areas (such as in the Florida Panhandle) when a hydraulically restrictive soil layer occurs near the pond bottom, it is common to excavate the restrictive soils beneath the pond bottom and backfill with a more permeable material in order to access the underlying permeable soil layer and improve pond recovery performance, as illustrated in Exhibit 1 below. This configuration is sometimes referred to as a “sand chimney”.
- How to account for tailwater condition when the tailwater elevation at the point of discharge is higher than the underdrain invert elevation?
In the PONDS Underdrain module the input parameters, based on the formula in Exhibit 1, are expressed as shown in Exhibit 2 below...
- Calculating Effective Length and Width of a Pond.
In the PONDS 3.2 Refined Method, the effective length and width determine the length of the perimeter which is available for saturated horizontal infiltration. PONDS assumes that the pond rectangular in shape (and the effective length and width are used to set up the finite difference grid used in Modflow for PONDS). However, real-world pond geometry is often irregular, or non-rectangular, so the actual pond must be approximated by an equivalent rectangular pond.
- Selecting Maximum Area for Unsaturated Infiltration.
Choosing the Maximum Area for Unsaturated Infiltration in PONDS 3.2 Refined Method module.
- Composite Curve Numbers and DCIA in PONDS SCS Hydrograph.
Composite Curve Numbers and DCIA, etc., in PONDS SCS Hydrograph.
- Modeling Multibasin / Interconnected Ponds
The following memo discusses the Multibasin SCS hydrograph in the PONDS 3.2 Refined Method software, and the use of this hydrograph type in modeling ponds with multiple runoff basins and/or for modeling a chain of cascading ponds.

Files Attached: Pond_1.prm, Pond_2.prm
- Using PONDS for Dewatering Analysis.
In PONDS, a dewatered excavation (or borrow pit) is modeled as a pond whose discharge structure elevation is set to the controlled water elevation during dewatering. The groundwater is then allowed to infiltrate (through background seepage) into the pond and is discharged through a control structure.
- Recommended Procedure for Selecting Base of Aquifer.
The procedures for selecting the base of the aquifer for modeling purposes are not always very straight forward and require judgment and experience in many cases...
- SWFWMD Memo - Determination of Kv and Kh in Surfacewater Management System Soil.
The purpose of this document is to provide general guidance for regulation review by district staff. The guidelines set forth herein may be modified in appropriate circumstances.
- Interfacing PONDS 3.2 with AdICPR v3.
PONDS 3.2 has the ability to interface with earlier versions of AdICPR (v1.4 and 2.x) by importing hydrographs directly from, or exporting hydrographs directly to, an ICPR *.hyd or *.bdq file...
- Interfacing Version 3.2 with adICPR 1.4 and 2.x.
Technical steps for developing detailed infiltration rating curves for each pond using the PONDS 3.2 computer code in conjunction with AdICPR (version 1.4 or 2.x).
- PONDS Version 2.26 Users Manual.

PONDS Software – Installation & Operation Errors

- Compatibility with Windows 7.
Some users have reported difficulty printing to Adobe Acrobat in Windows 7, and this compatibility setting has been effective in overcoming the printing problem with Adobe.
- Potential Device Driver Issues for Hardware Locks from Aladdin Knowledge Systems Ltd.
The following memo outlines some potential device driver issues for hardware locks manufactured by Aladdin Knowledge Systems Ltd. Two frequently seen products from Aladdin are the Hardlock and HASP hardware locks.
- Potential Issues in Windows Vistas.
In Windows Vistas, Microsoft has introduced a feature called User Account Control (UAC). In theory, this feature improves the security of your computer by overriding the Administrator user rights for local users and assigning regular user rights. One of the effects of this option is that Windows Vistas will frequently interrupt a process in order to ask you whether you want to proceed. Another consequence of the UAC is that it prevents users from saving files to the Program Files directory under some conditions. The PONDS software saves a number of data files in the C:\Program Files\Ponds32\ directory, including: temporary data files, recent files list, user options, etc. If the UAC is activated, it could prevent PONDS from operating as it should.
- PONDS 3.2 Compatibility Issue with Norton Antivirus.
We have updated the installation set for PONDS 3.2 to resolve an incompatibility issue between PONDS 3.2 and Norton Antivirus (as well as Avast Antivirus). It appears that on Dec 16, 2008, Norton Antivirus introduced some changes in their software that resulted in it misidentifying the PONDS 3.2 executable files as being infected with a virus. This is a FALSE POSITIVE, as we have no reason to believe that the files are actually infected. The problem stems from the fact that PONDS 3.2 was using older hardware locking software that had not been updated recently, as well as the new changes to Norton Antivirus.
- Device driver conflict with AdICPR version 3 for Windows.
Both PONDS and AdICPR v3 use hardware locks manufactured by Aladdin Knowldege Systems. Currently, the PONDS 3.2 Application Suite uses the Aladdin HASP hardware lock. However, previous versions of PONDS, including the standalone PONDS 3.2 Refined Method Module, have used the Aladding Hardlock LT hardware lock. Aladdin Knowledge Systems no longer supports the Harlock LT hardware lock.

Hydrology Notes and Publications

- Florida Stormwater Erosion and Sedimentation Control Inspector's Manual.
Florida Stormwater Erosion and Sedimentation Control Inspector's Manual.
- Pervious Pavement Systems and Excel Design Aid.
Provides additional information, training and reference materials to Professional Engineers so they may successfully design storm water management systems that meet their client’s objectives, while protecting the interests of the public..
- Coastal Engineering Manual (2002).
Engineer Manual 1110-2-1100, U.S. Army Corps of Engineers, Washington, D.C. (in 6 volumes).
- Definition of Directly Connected Impervious Area.
Definition of "Directly Connected Impervious Area" (DCIA), and its use in calculating surface water quantity rates and volumes in Surface Water Management Systems.
- Should the pond area be defined as Directly Connected Impervious Area (DCIA)?
FIRST, consider the meaning of the term DCIA (Directly Connected Impervious Area). The DCIA is the area which is directly connected to the pond. Rainfall that lands within the DCIA reaches the pond more or less instantaneously, and without a significant loss of volume.
- How to estimate Hydrologic Soil Group Using 2007 Criteria.
This chapter contains the official definitions of the various hydrologic soil groups. The National Soil Survey Handbook (NSSH) references and refers users to NEH630.07 as the official hydrologic soil group (HSG) reference. Updating the hydrologic soil groups was originally planned and developed based on this perspective.

General Engineering Notes

- Florida’s Sinkhole Database.
In this link you will find two different types of files. One is an Excel Spreadsheet and the other is an ESRI ArcGIS compatible shapefile. Both types of files have been provided as self extracting .exe and zipped files. Each file provides information on possible sinkholes as reported to the Florida Geological Survey and updated through September 4, 2009.
- Fill Berm Stability.
Although PONDS does not directly perform a stability analysis of a pond berm, it can be used to determine the seepage path through the berm in order to assess the likelihood of a seepage failure...

Methane Generation in Soil & Vapor Intrusion into Residential Structures:

- Indoor Air Vapor Intrusion Mitigation Approaches

The U.S. Environmental Protection Agency (EPA) Engineering Issue in one of a new series of technology transfer documents that sum- marize the latest available information on selected treatment and site remediation technologies and related issues.

- Proposed Regulatory Framework for Evaluating the Methane Hazard due to Vapor Intrusion
Methane is often found at percent levels in soil gas and it has become a chemical of concern at some vapor intrusion (VI) sites. The evaluation of methane, however, differs fundamentally from the evaluation of volatile organic compounds (VOCs) and the regulatory framework for addressing methane is either nonexistent or inadequate in most cases.

- Advisory On Methane Assessment And Common Remedies At School Sites.
This advisory provides guidance on investigations and common remedies for school sites where methane gas is the only chemical of concern present in subsurface soils. This advisory may be used to supplement remedies for sites with multiple contaminants in soil gas, e.g., hydrogen sulfide or volatile organic compounds (VOCs), in addition to methane...

- Method of estimating biogenic methane production at fill sites.
Methane is found in areas where buried organic materials decompose in the absence of oxygen. It is produced when methanogenic microbes convert organic materials into methane and carbon dioxide...

- FDOT Memo to Agencies Regarding Typical EMCs for N & P.
This memo is intended to clarify the Florida Department of Transportation (FDOT) - District One’s position on Event Mean Concentration (EMC) values used in nutrient loading calculations.

- Highway EMC for N & P based on FDOT Study.
Highway EMC for N & P based on FDOT Study.

- Drillers Well Log from 1886, St. Augustine, Florida.
Drillers Well Log from 1886, St. Augustine, Florida.

- USBR Publication on Design of Small Dams.
USBR Publication on Design of Small Dams.

- Storm Water Technology Fact Sheet (Bioretention).
Bioretention is a best management practice (BMP) developed in the early 1990's by the Prince George's County, MD, Department of Environmental Resources (PGDER). Bioretention utilizes soils and both woody and herbaceous plants to remove pollutants from storm water runoff.

- Storm Water Technology Fact Sheet (Bioretention).
Bioretention is a best management practice (BMP) developed in the early 1990's by the Prince George's County, MD, Department of Environmental Resources (PGDER). Bioretention utilizes soils and both woody and herbaceous plants to remove pollutants from storm water runoff.

- Preliminary Evaluation Of Wet Detention Pond Land Area Requirements With Proposed Fdep Stormwater Rule.
This memo provides a quantitative assessment of typical wet detention pond footprint area requirements based on the proposed stormwater quality treatment criteria which requires at least 85% reduction of the annualized post-development phosphorus load.

- Definitions of the Seasonal High Ground Water Table (SHGWT).
Formal definition of the Seasonal High Water Level (SHWL) from our District’s “Basis of Review” (BOR): Section 1.7.35 "Seasonal High Water Level" - The elevation to which the ground or surface water can be expected to rise due to a normal wet season.

- Efficiency Criteria.
This memo briefly discusses some issues regarding the water quality treatment volume calculations proposed in the draft FDEP Stormwater Quality Applicant's Handbook, and issues raised during meetings of the Technical Advisory Committee (TAC).

- Volume-Based Hydrology.
Examining the shift in focus from peak flows and pollution treatment to mimicking predevelopment volumes.

- Streambank and Shoreline Protection.
Engineering Field Handbook, Chapter 16, Part 650 of the NRCS National Engineering Handbook.

- Florida Rain Gardens.
A rain garden is a man-made depression in the ground or a bio-retention area used as a landscaping tool to improve water quality. The rain garden collects runoff from your roof, driveway and lawn, temporarily stores it, and permits it to be filtered and slowly absorbed by the soil.

- Seasonal Variability of Near Surface Soil Water and Groundwater Tables in Florida.
The water table and its range of fluctuation are required design factors for most projects that involve altering the landscape. In order to estimate the affect of a proposed alteration on surface water quality and quantity, it is necessary to determine the current or predevelopment water table conditions. Most regulations stipulate that no significant change can be imposed to these conditions. Typically, it is the maximum or high water level that is a required design criterion. Several terms have been adopted regarding the maximum high water level, with one of the most common terms being seasonal high groundwater table (SHGWT).

- Dealing with iron and other micro-irrigation plugging problems.
The objective of this document is to describe problems with emitter plugging and discuss management strategies to overcome and correct causes of plugging in micro-irrigation systems. This publication focuses, in particular, on iron scaling, documenting recent successes in treating this common problem in Florida. or if smaller particles stick together to form a much larger mass, then emitter plugging is likely. Filters are the primary defense against particles entering the micro-irrigation system. The most economical solution is to buy the best filtration.

- Blue-green algae in Florida waters.
Blue-green algae, or “cyanobacteria,” are structurally similar to bacteria but, like plants, use sunlight to grow. Blue-green algae occur naturally in both freshwater and marine (salt) water bodies. Most live with other types of algae and microscopic animals in floating “plankton.”

- Army Corp “Hydraulics of Flood Control Channels”.
This manual presents procedures for the design analysis and criteria of design for improved channels that carry rapid and/or tranquil flows.

- Hydraulics by King and Wissler.
published in 1922. A text book on hydraulics

The Florida Department of Environmental Protection (FDEP) is planning to adopt new state-wide stormwater treatment rules for the design of stormwater management systems. The new rules propose to adopt a requirement for no-net-increase in the pre vs postdevelopment nutrient loading in stormwater runoff from a site.

- Florida Friendly Landscaping Guide.
The Florida Yards & Neighborhoods (FYN) program addresses the serious problems of pollution in stormwater runoff, water shortages and disappearing habitats by enlisting Floridians in the battle to save our natural resources.

- Modeling Sinkholes in SWFWMD.
Sinkholes are a common occurrence in karst-sensitive areas throughout Southwest Florida. As development pressures continue, more comprehensive regulations need to be developed to protect the aquifer in karst-sensitive areas from untreated storm water.

- Estimating the normal Seasonal High Groundwater Table.
This article briefly describes the methods employed and factors considered by scientists and engineers in estimating the depth below land surface to the seasonal high groundwater table. Although this article focuses more on the Orlando (Florida) area, the methodology described herein is general and can be applied to other areas.

- Unit Hydrograph Shape Factor Memo from SJRWMD.
Sections 10.3 and 12.0 of the Management and Surface Waters (MSSW) applications handbook provides methodologies for calculating peak discharge in order to meet the peak discharge criteria in section 10.3 of the applicants handbook. The Handbook explains that peak discharge estimates should be make using a District approved hydrograph method...

- Criteria for Determining Hydrologic Soil Group.
Guidelines for Determining Hydrologic Soil Groups.

- Evaluation of Current Stormwater Design Criteria within the State of Florida.
This report, prepared by Environmental Research and Design, Inc. (July 2007) evaluates the current design criteria of each of the WMDs and DEP to determine whether the minimum treatment level specified in 62-40, F.A.C. is being met. It provides updated information on rainfall patterns, land use specific event mean concentrations, and BMP effectiveness. It provides recommendations on a new performance standard of post-development nutrient loading shall not exceed pre-development nutrient loading and BMP design criteria that can achieve this level of treatment.
- Remaining at Yield During Unloading and Other Unconventional Elastic-Plastic Response
A rather special time-independent or elastic-plastic response is proposed in which, although there is elastic response to unloading, the material remains at yield for all or a significant portion of the unloading path following plastic deformation...

- Inverse Condemnation in Flooding Cases
In the Old Testament Book of Genesis, God gets the credit or blame for a flood that covers the earth. (Genesis 6 - 7). In order to save Noah and his descendants, God orders Noah to build an ark of “gopher wood.”...

- Plasticity Theory for Granular Media - By Devo Seereeram in 1986
A Dissertation Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy.

- Application of a Bounding Surface Plasticity Law to the Prediction of Pressuremeter Tests - By Devo Seereeram in 1983
A thesis presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Engineering.

- Verification of Terzaghi's Theory of Consolidation by Centrifugal Testing - By Devo Seereeram in 1982
Documentation of geotechnical engineering project performed to graduate with title of High Honors (Bachelors degree) from University of Florida’s Civil Engineering College.
- Transmissivity of the Upper Floridan aquifer in Florida and parts of Georgia, South Carolina, and Alabama, 2012.
SCIENTIFIC INVESTIGATIONS MAP 3204, Transmissivity of the Upper Floridan aquifer in Florida and parts of Georgia, South Carolina, and Alabama, 2012 By Eve L. Kuniansky, Jason C. Bellino, and Joann F. Dixon

- Review of Aquifer Storage and Recovery in the Floridan Aquifer System of Southern Florida.
Reference: U.S. Geological Survey, Fact Sheet 2004-3128, November 2004

- Geological and Geotechnical Investigation Procedures For Evaluation of the Causes of Subsidence Damage In Florida.
A Report Submitted to the Florida State University, College of Business, Department of Risk Management and Insurance, In Response to Requirements of Chapter 627.7077 Florida Statutes
Florida Geological Survey Special Publication 57

- High Resolution Sea-Level History for the Gulf of Mexico since the Last Glacial Maximum.
Report of Investigations No. 103
Florida Geological Survey, Report of Investigation No. 103

- Florida Geological Survey Poster No. 16 (2009) titled “Hydrostratigraphic Units of Florida”.
Poster showing Florida Geological Survey Poster No. 16 (2009) titled “Hydrostratigraphic Units of Florida”.

- Hydrogeological Units of Florida, Florida Geological Survey Special Publication 28 (revised 2009).
In 1986, the Florida Geological Survey (FGS) published the first guidelines for naming Florida’s aquifers and confining systems (Southeastern Geological Society Ad Hoc Committee, 1986). These guidelines have served Florida well for 20 years but they concentrated on the most productive aquifers. Florida’s explosive growth has resulted in a need for developing expanded water sources, including less productive aquifers that were not emphasized in the 1986 guidelines. This report presents an updated set of guidelines for naming aquifers which changes the focus to all strata that are capable of producing water to a well and that have potential for public or private supply.

- Florida’s Sinkholes, Florida Geological Survey Poster No. 11 (2004).
Poster showing Florida’s Sinkholes, Florida Geological Survey Poster No. 11 (2004).

- Florida's Hydrogeologic Environment.
Poster showing Florida's Hydrogeologic Environment.
Florida Geological Survey Poster No. 5 (Revised)

- Earth Systems: The Foundation of Florida’s Ecosystems, by E. Lane and F. Rupert, 1996. (Florida Geological Survey Poster 6).
Poster showing Earth Systems: The Foundation of Florida’s Ecosystems, by E. Lane and F. Rupert, 1996. (Florida Geological Survey Poster 6).

- Geologic History of Florida, by L. Hatchett, 2000 (Florida Geological Survey Poster 7).
Poster showing the Geologic History of Florida, by L. Hatchett, 2000 (Florida Geological Survey Poster 7).

- Florida’s First Magnitude Springs.
Florida’s First Magnitude Springsheds.
Florida Geological Survey Poster No. 12

- Hydrology, Water Quality, and Aquatic Communities of Selected Springs in the St. Johns River Water Management District, Florida.
Hydrologic, physicochemical, and aquatic community data were collected and compiled by the U.S. Geological Survey (USGS) for selected springs within the St. Johns River Water Management District (SJRWMD) from January 2004 to October 2007...

- Ancient Sea Level Stands in Florida
This report was prepared in cooperation with the University of Florida and is the first of several that will result from a study of the heavy minerals in Florida.
Florida Geological Survey, Bulletin No. 52

- Florida's Geological History and Geological Resorces
This publication presents the Geological history of Florida and its natural resources.
Florida Geological Survey, Special Publication No. 35

- Springs of Florida, Florida Geological Survey Bulletin 66 (2004)
There are two general types of springs in Florida, seeps (water-table springs) and karst springs (artesian springs). Rainwater, percolating downward through permeable sediments, may encounter a much less permeable or impermeable formation, forcing the water to move laterally...

- Tracer studies and background fluorescence of ground water in the Ocala, Florida area. (1967)
By D.W. Knochenmus, 1967; U.S. Geological Survey Open-File Report 67004

- Geohydrology Of The Crossflorida Barge Canal Area With Special Reference To The Ocala Vicinity (1973)
By Glen L. Faulkner, USGS, 1973; Water-Resources Investigations Report I-73

- Quantity and quality of surface water in Marion County, Florida (1973)
By W. Anderson and G.L. Faulkner, 1973,: Florida Bureau of Geology Map Series 55.

- Aquifer tests in the Summit reach of the proposed Cross-Florida Barge Canal near Ocala, Florida: (1975)
By C.H. Tibbals, 1975. U.S. Geological Survey Water Resource Investigations 28-75.

- Geohydrologic Reconnaissance Of Drainage Wells In Florida (1984)
By Joel O. Kimrey and Larry D. Fayard. U.S. GEOLOGICAL SURVEY Water-Resources Investigations Report 84-4021

- Environmental Geology and Hydrogeology of the Ocala Area, Florida (1991)
By Ed Lane and Ron Hoenstine, Florida Geological Survey, Special Publication No. 31

- Origin of nitrate in ground water discharged from Rainbow Springs, Marion County, Florida (1996)
By G.W. Jones, S.B. Upchurch, and K.M. Champion. 1996,: Ambient Ground-Water Quality Monitoring Programm Southwest Florida Water Management District.

- Estimation of Evapotranspiration in the Rainbow Springs and Silver Springs Basins in North-Central Florida (1996)
By Leel Knowles, Jr. U.S. Geological Survey Water-Resources Investigations Report 96-4024

- Chemistry of GroundWater in the Silver Springs Basin, Florida, with an Emphasis on Nitrate (2004)
By G.G. Phelps, U.S. GEOLOGICAL SURVEY Scientific Investigations Report 2004-5144