United States Department of Agriculture
Natural Resources Conservation Service		 Iowa Go to Accessibility Information
Skip to Page Content





 
 
 
 

Iowa Pond (Version 5.31)

Introduction

The program outlined in the following pages has been written to provide a useful tool in the design of ponds and structures that do not require TR-60 criteria for the design. The routings associated with the use of this program are consistently within 0.2 foot of DAMS - 2 routings for emergency spillway elevations. It is to be noted that the output is only good as the input to the program.

Equipment

The program has been written to operate in the MS-DOS environment. The program will run on equipment with 640K RAM and a printer. To insure that the program has sufficient memory to operate, resident memory programs must be kept at a minimum. The program requires a minimum of 400K ram (free to the program) available to operate. NOTE: In order to use the rainfall editing program and a program that computes a runoff curve number fro within the HYDRO-YARDAGE program requires a minimum of 530K RAM (free to the program). Graphics capability is required for some of the input screens. The program was written in QuickBasic 2.0 and has been compiled in order to maximize performance.

In order to use this program with a variety of printers, a special section of the program allows the user to enter printer codes for a printer that has not been previously defined. Please refer to the Defaults section of this manual for further information.

Key Functions

This program has been written to be as 'friendly' as possible. In most cases the inputs requested from the user are light colored cells or rectangles located for data entry. When a request for an answer is either "(y/n)" the program will accept either upper or lower case characters. The program uses function keys to maneuver between screens. All data entries are not recorded in the program until "RETURN" has been pressed.

Messages

The bottom row of the screen display the function key displays for the maneuvering between screens. As data is entered for some of the data entries "help" lines "pop up" to help in the interpretation of data entries. In other words, "What does the program need in this data entry for the program to proceed ?".

Errors

Many error conditions have been trapped within the program. Various messages will appear in order for the user to rectify errors prior to proceeding with the remaining parts of the program. Typical errors trapped are when the program is expecting numbers instead of letters and the data entry is to long. Other messages that appear are when insufficient data is entered for the program to function. A great deal of effort has been made to get the so called "bugs" out of the program, but unforeseen and uncommon data entries or attempting to make the program do what it was not intended to do, may still create these "bugs".

Saved Data

Input data is saved for each routing in the directory ".\namefile" with an extension of ".nme". The elevation-pond area file for this routing is filed in the directory ".\pondarea" with an extension of ".pol" and the centerline profile of station and elevation for earthwork quantities is filed in the directory ".\crossect" with an extension of ".xse". All of the default files are located in the directory ".\hydata" with extensions of ".dft" while the printer defaults are located in the directory ".\printer" with extension of ".dft". The directory ".\hydro" contains the unit hydrographs for the program and use extensions of ".dat". Earthwork files, strictly for earthwork quantities (no routing), are located in the directory ".\eartdata" with extensions of ".eda".

Programs

The HYDRO-YARDAGE program makes use of four programs 'chained together' to function. The following is a brief description of each.

  1. MENUHYD.exe - this program contains the HYDRO-YARDAGE menu, default setup screens and file deletion screens.
  2. INPROUT.exe - this program contains the data entry screens for the routing program.
  3. HYDROUT.exe - this program contains the routing portion.
  4. EARTONLY.exe - this program contains the data entry screens for earthwork computations only (for a non-routed structure). It is to be noted that the INPROUT.exe program also contains Earthwork data entry screens.
  5. SUBSLIB.exe - this program contains a library of subroutines that is loaded into memory with the above programs and is made available to all programs.
  6. HIVE.exe - this program is used to archive files from the hard disk to floppy disks.
  7. RAINEDIT.exe - a utility program that edits, adds to or creates a rainfall file that is used with the HYDRO-YARDAGE program.
  8. TIMECONC.exe - a utility program that computes a time of concentration using the RCN method.
  9. CONVRAIN.exe - utility program that converts existing county.xx rainfall files created for EFM2 and TR55 into RAIN.DAT files for use by the HYDRO-YARDAGE program.

Program Capabilities

The HYDRO-YARDAGE program provides a incremental routing of a pond or structure. The program uses tabular unit hydrographs types I, Ia, II and III from TR-55. The files for these hydrographs contain ia/p of 0.1, 0.3 and 0.5. The hydrographs are for a travel time of 0.0 hours. The time of concentrations range from 0.1 hour (6 minutes) to 2.0 hours (120 minutes). The program does not interpolate between Tc's to arrive at discharges, but uses the Tc file that is the nearest. For example, if the Tc equals 0.13 hours as computed by the program, the program will select the Tc file with a Tc of 0.1 hour. The program will interpolate within the Tc file to arrive at the discharges for a given ia/p. As stated, only time of concentration ranging between 6 minutes and 120 minutes are allowed.

Curve number within the program are limited to a range from 30 to 99.

The rainfalls for this program are P1, P2, P5, P10, P25, P50 and P100 24 hour storms. These are entered in the defaults section of the program.

Cost estimates for the structure or pond are calculated using costs as set up by the user in the defaults part of the program.

The types of principal spillway, inlets and outlets the program will route are as follows:

Principal spillway types
  1. Corrugated metal pipe
  2. Smooth metal pipe
  3. Smooth plastic pipe
  4. Reinforced concrete pipe
Inlets
  1. Hood inlets
  2. Canopy inlets
  3. Drop inlets
Outlets
  1. Cantilever
  2. Slotted flume

The emergency spillway bottom widths, crest lengths and vegetated retardance are entered by the user. The program can use A, B, C, D and E retardance for each individual run in routing the emergency spillway. The criteria for the emergency spillway was taken from the Engineering Field Manual, Chapter 11.

The remaining parts of this manual use a slightly different approach in explaining the process of using the software. The approach used is to take the user step by step through an example run, while explaining each individual step involved in the process.

Program support:

Norman Friedrich
Civil Engineer
120 N Industrial Prkwy #4
West Union, Iowa 52175

< Back to Engineering Programs