WQ0042731_More Information Received (2)_20220218

NC DENR Division of Water Quality Version 5 December 2004
Introduction
In this program the water balance procedure is broken down into the following separate worksheets;
The Precipitation Worksheet,
The Potential Evapo-transpiration (PET) Worksheet,
The Influent & Zone Setup Worksheet,
Zone 1 through Zone 10 Worksheets, and
The Zonal Sums Worksheet, which sums up all the Required Storage Terms from the
individual Zone 1 through Zone 10 Worksheets.
Each of these worksheets require data input in only a few steps. When the required input has been
completed for all the worksheets, the Water Balance will be automatically generated and ready to verify
that all the required parameters fit. It may be necessary, however, to perform several iterative attempts
before a final water balance is achieved.
This program accounts for those spray irrigation applications where significant differences exist across
an application area such that discreet "zones" should be created. After successfully completing a separate
water balance for each zone, a zonal calculations worksheet then computes the minimum storage requirements
necessary for the entire application area under consideration.
I. General Information:
Precipitation
PET Soil Drainage
Lagoon Gains
and Losses
Water Budget Storage Required
This program was created in Excel 2000. Each user should adjust the Excel zoom/display capabilities
to maximize each sheet for their particular computer setup.
Once an appropriate water balance solution has been achieved, the applicant should
make hard copies of all the worksheets and the final water balance and include them
as part of any application package requiring a water balance analysis.
II. Required Information:
In order to complete this procedure the following data is required:
Long term, 30 year (approx.), precipitation data from a source close to the site under consideration
Data required includes average monthly rainfall, and 80th percentile yearly rainfall values
Long term, 30 year (approx.), temperature data from a source close to the site under consideration
Data required includes average monthly temperatures, and average monthly pan evaporation
values.
Facility design data
Data required includes design influent capacity, lagoon/storage acreage (estimate), and spray field area.
In-situ soils data
Data required includes actual in-situ saturated vertical hydraulic conductivity values for the soils
under consideration to receive wastes.
III. Background Information
The water balance program was designed to assist permit applicants in meeting the minimum design requirements
of NCAC 15A.2H.0200 for surface irrigation disposal/treatment systems. The soil drainage methodology used within this
program is referenced from EPA 625/1-81-013, Process Design Manual, Land Treatment of Municipal Wastewater.
The Surface Irrigation Water Balance Example
All the worksheets included in this program are designed to be self educating. A step by
step approach has been instituted to assist those first time users who may not be familiar
with the water balance procedure. These steps are also designed to help re-familiarize
those users that are not new to the water balance procedure, but may only use this
program a few times a year.
For all the worksheets included in this package, specific step by step instruction windows
will appear when you place your mouse courser on and click each of Step 1
the "Step" buttons.
Cells which require data input used in the calculations (active cells) are indicated by the
use of green colored, solid, dark bordered cells.
Yellow cells indicate calculated worksheet results that are linked to other worksheets
or the Water Balance. Additional links are provided throughout
the program to assure that only a minimum of data has to be entered
more than once.
General information about the actual calculations used can be found by clicking on
each of the "Calculations" boxes below each column.
More detailed information regarding calculations,
with specific examples, can be found on the Calculations Sheet (the very last tab).
Additional help and background information is provided by clicking on the FYI and Help
buttons provided in each worksheet.
In order to assure that the Water Balance is properly calibrated and converges, see FYI box
next to the Water Balance, ALWAYS click on the MACRO button
on the upper right hand side of the Water Balance, whenever
any changes are made to the Water Balance Program.
When the macro button is pushed, a "behind-the-scenes" macro program
calculates the Storage terms in the Water Balance.
For each Zone sheet, when complete, click on the
macro "Calculate" Button (Example: Zone 1 Calculate Button)
Also, you can click on the "Master Calculate Button"
located in the "Influent+Zones Setup" Sheet. This macro
button will quickly perform the Storage calculations for all 10 Zones.
You will note that the computer quickly switches through all 10 Zones
during this calculation process.
Complete as much of the required information in the Project Identification Page as you can.
We suggest that you rename the electronic file by the Water Quality permit number,
if available.
(This action will insure that the Permit Number appears on the bottom of each submitted sheet)
This program is setup so that one starts with the first workbook tab at the bottom left of
the screen and moves incrementally from tab to tab, left to right. As listed below in the
FYI HELP
Calculations
CALCULATE
BUTTON
for Zone 1 (only)
to Calculate Monthly
Cummulative Storage
Master CALCULATE
BUTTON
for All 10 Zones
to Calculate Monthly
Cummulative
Storage
contents, this program accounts for up to four distinct water balance "zones". If, however,
your particular situation warrants fewer zones then only fill out the number of zones you
require. Leave the other zone worksheets attached but empty. If your particular application
situation only warrants a single zone, then the minimum required storage can be
determined directly from the lower right-hand corner of the water balance for Zone 1.
In cases of more than a single zone, the minimum storage requirements must be determined
from the Zonal Calculations Sheet.
Table of Contents
(from left workbook tab to right)
Tab Title
Read Me First Introduction
Instructions (Please read all the instructions)
Project Id Project Identification Worksheet
"No Storage" Q.W.B."No Storage" Quick Water Balance (This was added in Version 4 to facilitate
quick water balance calculations assuming no there is no storage. The
irrigation performed is assumed to be the Maximum Allowable Irrigation.)
Precip Precipitation Worksheet
PET Potential Evapotranspiration Worksheet
Influent+Zones Setup Influent, Lagoon and Zone Setup Worksheet
Zones 1 - 10 Soil Drainage and Irrigation Worksheet, Zones 1 - 10
Zonal Sums Zonal Summation of Required Storage Worksheet
Calcs Calculations Sheet
Step by step instructions are provided on each of the individual worksheets.
The following is a brief list of the operations required:
A. Starting with the Precipitation Worksheet
1. Enter the mean monthly precipitation data in the green cells.
2. Enter the 80th percentile yearly precipitation value in the single green cell.
3. Enter data source information.
B. Complete the PET Worksheet
1. Choose either the Thornthwaite Method or the Manual PET data by clicking on checkbox.
2. For Thornthwaite Method:Enter the mean monthly temperature data in the green cells.
Enter the site latitude in the single green cell.
3. For Manual PET data:Enter the PET data directly in the green cells.
4. Enter data source information.
C. Complete the Influent and Zones Setup Worksheet
1. Enter the mean monthly pan evaporation data in the green cells.
2. Enter the design daily influent in the single green cell.
3. For each Zone, enter the flow and sprayfield area in the green cells.
If a Zone is not used, simply enter zero into the flow and/or sprayfield area.
D. Complete Zone 1 through Zone 10 Worksheets
1. Enter the Ksat of the most restrictive soil horizon in the single green cell.
2. Select and enter the appropriate drainage factor in the single green cell.
3. Complete the site soils information
*****4. As an added feature, the User is allowed to manually override the Maximum Allowable Irrigation (M.A.I.)
The purposed of this is to allow the User to alter the actual Max. Allowable Irrigation used by the Water Balance
Example: Suppose the Water Balance calculates that the Maximum Allowable Irrigation, and the User
wants to limit the irrigation in the Winter Months of December, January, and February to zero because
of known site conditions. He does this simply by placing zeros into the "Manual Override" cells
for that particular month. See below as an example:
Calculated Manual
Override Actual Used
Month Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
inches inches inches
January 3.15 0.00 0.00
February 2.62 0.00 0.00
March 4.11 4.11
April 6.03 6.03
May 5.84 5.84
June 5.39 5.39
July 5.38 5.38
August 5.07 5.07
September 4.39 4.39
October 5.95 5.95
November 4.81 4.81
December 3.77 0.00 3.77
Totals:56.50 50.73
The Water Balance is calculated using the "Actual Maximum Allowable Irrigation", and the Water Balance will not not allow irrigation
to take place in the three Winter months of Decmeber, January, and February.
If all the above steps have been completed, the Water Balance has been
automatically calculated for you.
1. If a red convergence message appears below the macro button, then the water balance
is properly balanced.
OR:
2. If a red Error message appears below the macro button, then the water balance is not
properly balanced, and additional adjustment is required.
3. After making any revisions to the worksheets, verify the results in the
Water Balance Sheet by clicking on the macro button. Continue the
adjustment process until the water balance is properly estimated.
Water Balances that involve more than a single zone, must use the Zonal Calculations
Sheet to compare and compute minimum storage requirements by individual months
and zones. This sheet is self generating, so if the water balances for each zone have
been properly determined, the minimum cumulative storage requirements across all
zones will be displayed.
As also noted in the Soil Drainage Worksheet, an average or weighted Ksat may be calculated
for those small spray field sites (less than 5 acres) that are made up of soils with significant
differences in hydrologic properties. In these cases, the minimum storage requirements
can be determined directly from the Water Balance Sheet.
For sites larger than 5 acres where the soils exhibit significant differences in hydrologic
properties, an appropriate consideration shall be made to address these differences.
In cases such as these, the site shall be subdivided and designed in separate zones,
based on the ability of each portion of the site to receive wastes. A zone is essentially any
area that has a markedly different capacity to receive irrigation. The most likely attribute
which might trigger the segregation of a particular application area into two or more zones,
is that of saturated vertical hydraulic conductivity (Ksat). Significant differences in Ksat
will most likely exert the greatest control over the required land area. A word of caution
needs to be emphasized here. While soil permeability and Ksat are closely related, Ksat as
used in this procedure means in-situ measured saturated vertical hydraulic conductivity.
The use of published soil permeability rates should not be used. These values do not
incorporate significant site specific factors, which can render these gross generalizations
inappropriate for use. Other site factors to consider may include seasonal limitations
do to shallow water tables, clays which may exhibit variable permeabilities with changes in
moisture status, shallow soils, shallow bedrock, etc. Some of these possible limitations as
they are commonly associated with specific soils are provided as a reference in the Soils
Information in each zone sheet. The major point here, is that any possible factor that may
render a section of a particular site less or more capable of receiving irrigation should
facilitate that section being segregated into a separate zone. The determination of significant
difference is up to the designer.
A separate water balance shall be generated for each zone (each "Z" sheet). In order to properly
esimate the minimum required storage, the data generated from each zone's water balance
calculations is linked to the Zonal Calculations Sheet. This sheet serves to determine
the most likely maximum storage needs for an entire year, across the entire application site.
It takes into account that the periods of maximum storage demand may vary between
individual zones.
The Precipitation, PET and Influent+Zones Setup Worksheets should only have to be created once per site.
The Influent+Zones Setup Worksheet, among other things, calculates the direct rainfall into
the Storage Lagoon and the evaporation out of the Storage Lagoon. This is the reason
for entering the Area of the Lagoon. If there is no lagoon, or the basin if covered, etc., then
enter zero for this parameter.
This program is set up to handle up to 10 separate zones. For applications where more
than 10 separate zones are designed, please contact Ken Pohlig (see below) for a version
of this program that allows for more zones.
Note:The minimum volumetric storage requirements calculated in this procedure do not
represent the actual minimum design requirements for storage structures. The
volumetric values calculated under this procedure only accounts for that area above
the permanent pool level and below the minimum freeboard requirements.
Once the physical dimensions of any lagoons have been determined, the actual areal
footprint of the lagoons should be compared to the original lagoon area estimates.
At the present time, Division of Water Quality policy requires that a minimum of 30 days
storage be provided for every spray irrigation facility. This policy decision has not
been incorprated within the results of the water balance program.
Ken Pohlig Division of Water Quality/ Construction Grants & Loan Section
Phone: [phone] e-mail: Ken.Pohlig @ ncmail.net
A Spray Irrigation Water Balance for
Permit No:WQ0042731
Permittee Name:Judge Legacy Enterprise
Contact Name:Bryan Judge
Address:
Facility In The Pines RV and Cabin Village
Address:
Water Budget Prepared By:
1600 George II Hwy SE, Bolivia, NC 28422
129 South Palm Drive, Winnabow, NC 28479
Nicholas P Howell NCLSS #1294, SSSA Soil
Scientist #328892, Davey Resource Group Inc., dba
Land Management Group, 3805 Wrightsville Ave.
STE 15, Wilmington, NC 28403
DRGNCW20.426_Waterbalance_Wilm_FEB_2022 Project Id Version 5 December 2004
Quick Water Balance for:Example Site
Quick Water Balance Assuming No Storage
Spray Irrigation Area = 2 acres Input ==>
Output =>
Limiting Soil Ksat =0.115 inch/hour
Drainage Coefficient =0.100
Kv = Ksat * (Drainage Coeff.) =0.2748 inch/day
# of Days Maximum Maximum Maximum
in Vertical Monthly Allowable Allowable Allowable
Month ET Drainage Precipitation Irrigation Irrigation Irrigation
(days)(in/mo)(in/mo)(in/mo)(in/mo)(gallons/day)(gallons/month)
January 31 0.90 8.52 4.10 5.32 9,315 288,751
February 28 1.40 7.69 4.30 4.79 9,293 260,204
March 31 2.20 8.52 4.44 6.28 11,005 341,144
April 30 3.30 8.24 4.41 7.13 12,915 387,462
May 31 4.30 8.52 4.62 8.20 14,364 445,294
June 30 4.80 8.24 5.28 7.76 14,056 421,679
July 31 4.70 8.52 6.12 7.10 12,437 385,550
August 31 4.00 8.52 5.42 7.10 12,437 385,550
September 30 3.30 8.24 4.80 6.74 12,209 366,281
October 31 1.90 8.52 3.42 7.00 12,262 380,119
November 30 1.20 8.24 3.30 6.15 11,128 333,830
December 31 0.70 8.52 4.09 5.13 8,984 278,496
TOTAL = 365 32.70 100.30 54.30 78.70 4,274,360
Formulas: (Max. Allowable Irrigation) = (ET) + (Drainage) - (Precipitation)
Note: This sheet is independent of
all the remaining sheets. This "No
Storage" quick water balance
assumes that the amount irrigated is
equal to the calculated Maximum
Allowable Irrigation.
DRGNCW20.426_Waterbalance_Wilm_FEB_2022 "No Storage"Version 5 December 2004
Enter Data ===> Precipitation Worksheet
Calculate the precipitation for an 80th percentile "wet" year, based on long term data (approx. 30 years or greater).
Click on each step box
Step 1 Step 2
Month
Mean Monthly
Precipitation
Percent of Mean
Annual Precipitation
80th Percentile
Monthly
Precipitation
inches percent inches Location of Precipitation Data:
January 3.76 6.28 4.71
February 3.43 5.72 4.30 Staring Year of Data Record:1990
March 4.00 6.68 5.01
April 3.05 5.09 3.82 Ending Year of Data Record:2020
May 4.66 7.78 5.84
June 5.56 9.28 6.97 Period of Record (Years) = 30
July 6.85 11.43 8.59
August 8.26 13.79 10.36
September 8.45 14.10 10.59
October 4.74 7.91 5.94
November 3.51 5.86 4.40
December 3.65 6.09 4.58
TOTALS =59.92 100.00 75.12
Calculations Calculations
FYI
Step 4
Step 3 - Precipitation Data Soucre
Wilmington WSO AP, NC 9457
Important Note: Period of record for precipitation data should
match period of record for temperature data
Precipitation Data
Values shown in yellow
cells are linked to other
locations within the Water
Balance Program
Other (List Below)
https://www.wcc.nrcs.usda.gov/climate/navigate_wets.
html
Source of Data:
DRGNCW20.426_Waterbalance_Wilm_FEB_2022 Precip Version 5 December 2004
Enter Data ===> Potential Evapo-Transpiration (PET) Worksheet
Choose PET Method: Thornthwaite Method Click on CheckBox Manually Entered PET
Click on each step box
Thornthwaite PET Calculation PET Data
Step 1 Step 2 Step 4
Month
Mean monthly
temp.
Daylight
hours / 12 Heat index
Calculated
PET Site Latitude
Manually
Entered PET
Data
(degrees F)inches degrees (inches)
January 57.4 0.88 4.81 0.72 0.90 0.72
February 60.4 0.85 5.70 0.98 1.40 0.98
March 66.5 1.03 7.65 2.11 within range 2.20 2.11
April 74.6 1.09 10.52 4.16 3.30 4.16
May 81.0 1.20 13.01 6.97 4.30 6.97
June 87.0 1.20 15.49 9.80 4.80 9.80
July 89.9 1.22 16.75 11.62 4.70 11.62
August 88.2 1.16 16.01 10.05 4.00 10.05
September 83.9 1.03 14.19 7.07 3.30 7.07
October 76.1 0.97 11.09 4.12 1.90 4.12
November 67.4 0.87 7.95 1.91 1.20 1.91
December 60.4 0.86 5.70 0.98 0.70 0.98
TOTALS = 128.87 60.50 32.70 60.50
Calculations Calculations Calculations Calculations
1990
2020
30
Note: Period of record for Temperature data
should match period of record for Precipitation
data
FYI 2
34.01
Step 6
Step 5
Other
https://www.wcc.nrcs.usda.gov/climate/navigate_wets.html
FYI 1PET Data
used in
Water
Balance
Step 3
Values shown in
yellow cells are
linked to other
locations within the
Water Balance
Program
Source of Temperature Data Source of PET Data
Source of Data:
Location of Precipitation Data:
Staring Year of Data Record:
Ending Year of Data Record:
Period of Record (Years) =
Wilmington WSO AP, NC 9457
DRGNCW20.426_Waterbalance_Wilm_FEB_2022 PET Version 5 December 2004
Step 2 Step 3 Step 4
Area of
Lagoon
Design Daily
Flow (Influent)
Total Flow to
All Zones
Daily Flow to
Zone 1
Wetted
Acreage
Daily Flow to
Zone 2
Wetted
Acreage
Daily Flow to
Zone 3
acres gals/day gals/day acres gals/day acres gals/day
0.00 5,510 gals/day gals/day 5,510 2.70 0 0.00 0
Click on each step box 5,510 5,510
Enter Data ==> Precip Influent Irr. Rate
(in/wk) =0.53 Irr. Rate
(in/wk) =
Irr. Rate
(in/wk) =
Step 1
Month
Days
per
month
Pan
Evaporation
Data
Adjusted
Pan Data Precip
Lagoon
Gains from
Precip.
Lagoon
Losses from
Evap.
Design Influent
Volume per
Month
Total: Influent +
Lagoon Gains &
Losses
Zone 1
Volume to be
Disposed
Zone 1
Design
Irrigation per
month
Zone 2
Volume to be
Disposed
Zone 2
Design
Irrigation per
month
Zone 3
Volume to be
Disposed
inches inches inches gallons gallons gallons gallons gallons inches gallons inches gallons
January 31 1.30 0.91 4.71 0 0 170,810 170,810 170,810 2.33 0 0.00 0
February 28 1.96 1.37 4.30 0 0 154,280 154,280 154,280 2.10 0 0.00 0
March 31 3.69 2.58 5.01 0 0 170,810 170,810 170,810 2.33 0 0.00 0
April 30 4.91 3.44 3.82 0 0 165,300 165,300 165,300 2.25 0 0.00 0
May 31 6.16 4.31 5.84 0 0 170,810 170,810 170,810 2.33 0 0.00 0
June 30 6.63 4.64 6.97 0 0 165,300 165,300 165,300 2.25 0 0.00 0
July 31 6.96 4.87 8.59 0 0 170,810 170,810 170,810 2.33 0 0.00 0
August 31 6.21 4.35 10.36 0 0 170,810 170,810 170,810 2.33 0 0.00 0
September 30 4.61 3.23 10.59 0 0 165,300 165,300 165,300 2.25 0 0.00 0
October 31 3.29 2.30 5.94 0 0 170,810 170,810 170,810 2.33 0 0.00 0
November 30 2.01 1.41 4.40 0 0 165,300 165,300 165,300 2.25 0 0.00 0
December 31 1.41 0.99 4.58 0 0 170,810 170,810 170,810 2.33 0 0.00 0
Calcs.Calcs.Calcs.Calcs.Calcs.Calcs.Calcs.Calcs.Calcs.Calcs.
Totals:365 49.14 34.40 75.12 0 0 2,011,150 2,011,150 2,011,150 27.43 0 0.00 0
Step 6
Other (List Below)
https://www.wcc.nrcs.usda.gov/
climate/navigate_wets.html
Lagoon Gains & LossesPan Evap. Data
Influent, Lagoon Storage,
and Zone Setup Worksheet
Source of PAN Evap. Data
Calculate the adjusted influent loading by including the gains
and losses from the Storage Lagoon, and set up the Spray
Zones areas and individual Zone flowrates.
Total Flow to be
Disposed
(Annual
Averaged)
should be
equal
Zone 1 Zone 2 Zon
DRGNCW20.426_Waterbalance_Wilm_FEB_2022 Influent+Zones Setup Version 5 December 2004
Wetted
Acreage
Daily Flow to
Zone 4
Wetted
Acreage
Daily Flow to
Zone 5
Wetted
Acreage
Daily Flow to
Zone 6
Wetted
Acreage
Daily Flow to
Zone 7
Wetted
Acreage
Daily Flow to
Zone81
Wetted
Acreage
Daily Flow to
Zone 9
Wetted
Acreage
Daily Flow to
Zone 10
Wetted
Acreage
acres gals/day acres gals/day acres gals/day acres gals/day acres gals/day acres gals/day acres gals/day acres
0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00
Irr. Rate
(in/wk) =
Irr. Rate
(in/wk) =
Irr. Rate
(in/wk) =
Irr. Rate
(in/wk) =
Irr. Rate
(in/wk) =
Irr. Rate
(in/wk) =
Irr. Rate
(in/wk) =
Zone 3
Design
Irrigation per
month
Zone 4
Volume to be
Disposed
Zone 4
Design
Irrigation per
month
Zone 5
Volume to be
Disposed
Zone 5
Design
Irrigation per
month
Zone 6
Volume to be
Disposed
Zone 6
Design
Irrigation per
month
Zone 7
Volume to be
Disposed
Zone 7
Design
Irrigation per
month
Zone 8
Volume to be
Disposed
Zone 8
Design
Irrigation per
month
Zone 9
Volume to be
Disposed
Zone 9
Design
Irrigation per
month
Zone 10
Volume to be
Disposed
Zone 10
Design
Irrigation per
month
inches gallons inches gallons inches gallons inches gallons inches gallons inches gallons inches gallons inches
0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00
0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00
0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00
0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00
0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00
0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00
0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00
0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00
0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00
0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00
0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00
0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00
Calcs.Calcs.Calcs.Calcs.Calcs.Calcs.Calcs.Calcs.Calcs.Calcs.Calcs.Calcs.Calcs.Calcs.Calcs.
0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00
Zone 9 Zone 10Zone 5 Zone 6 Zone 7 Zone 8ne 3 Zone 4
DRGNCW20.426_Waterbalance_Wilm_FEB_2022 Influent+Zones Setup Version 5 December 2004
Values shown
in yellow cells
are linked to
other
locations
within the
Water Balance
Program.
Step 5
DRGNCW20.426_Waterbalance_Wilm_FEB_2022 Influent+Zones Setup Version 5 December 2004
Soils and Water Balance for Zone 1
Drainage class BLS = below land surface
mod well 2.0-3.0 low no
Step 1 Step 2 f x Ksat s poorly 1.5 - <2.0 low no
poorly LS - <1.5 low yes
in/hr in/day percent in/day
0.10 2.40 0.080 0.19 Daily Flow = 5,510 gals/day
Zone 1 Area = 2.70 acres
Zone 1 Zone 1
Calculated Manual
Override Actual Used
Month Days per
month PET
Zone 1
Soil
Drainage
Zone 1
Total
Loss
Precip
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Design Irrigation
per Month
Monthly
Excess
inches inches inches inches inches inches inches inches inches inches inches
January 31 0.72 5.98 6.70 4.71 1.99 1.99 2.33 -0.34 0.34 1.99
February 28 0.98 5.40 6.38 4.30 2.08 2.08 2.10 -0.02 0.36 2.08
March 31 2.11 5.98 8.09 5.01 3.07 3.07 2.33 0.74 0.00 2.69
April 30 4.16 5.79 9.95 3.82 6.12 6.12 2.25 3.87 0.00 2.25
May 31 6.97 5.98 12.95 5.84 7.11 7.11 2.33 4.78 0.00 2.33
June 30 9.80 5.79 15.59 6.97 8.62 8.62 2.25 6.37 0.00 2.25
July 31 11.62 5.98 17.61 8.59 9.02 9.02 2.33 6.69 0.00 2.33
August 31 10.05 5.98 16.03 10.36 5.68 5.68 2.33 3.35 0.00 2.33
September 30 7.07 5.79 12.86 10.59 2.27 2.27 2.25 0.01 0.00 2.25
October 31 4.12 5.98 10.10 5.94 4.16 4.16 2.33 1.83 0.00 2.33
November 30 1.91 5.79 7.70 4.40 3.30 3.30 2.25 1.04 0.00 2.25
December 31 0.98 5.98 6.96 4.58 2.39 2.39 2.33 0.06 0.00 2.33
Calcs.Calcs.Calc. M.A.I.Manual M.A.I.M.A.I. Used Calcs.
Totals:365 60.50 70.43 130.93 75.12 55.81 55.81 27.43 27.43
Maximum Monthly Storage Required for the Irrigation of Zone 1:
inches acres gallons
0.36 over 2.70 =26,459
Soil
Drainage
Rate
Zone 1 Description:
Potential site limitations
Is bedrock <
60" BLS ?
Soils Series Information for Zone 1
Series Name
Water table depth
(BLS)
risk of
perching
FYI
HELP
Actual
Monthly
Irrigation Rate
Click the
"CALCULATE"
button after making
changes.
Cummulative
Storage
Required for
Irrigation
Copied from Influent & Zones Setup Sheet:
Calculate Soil Drainage Published soil permeability
rates by series or textural class
are not acceptable. Actual in-
situ soils Ksat data is required.
Goldsboro
Lynchburg
RainsIn-situ saturated vertical
hydraulic conductivity
(Ksat)
Drainage
factor (f)
DRGNCW20.426_Waterbalance_Wilm_FEB_2022 Z1 Version 5 December 2004
Soils and Water Balance for Zone 2
Drainage class BLS = below land surface
Step 1 Step 2 f x Ksat
in/hr in/day percent in/day
0.17 4.08 0.050 0.20 Daily Flow = 0 gals/day
Zone 2 Area = 0.00 acres
Zone 2 Zone 2
Calculated Manual
Override Actual Used
Month Days per
month PET
Zone 2
Soil
Drainage
Zone 2
Total
Loss
Precip
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Design Irrigation
per Month
Monthly
Excess
inches inches inches inches inches inches inches inches inches inches inches
January 31 0.72 6.32 7.05 4.71 2.33 2.33 0.00 2.33 0.00 0.00
February 28 0.98 5.71 6.69 4.30 2.39 2.39 0.00 2.39 0.00 0.00
March 31 2.11 6.32 8.43 5.01 3.42 3.42 0.00 3.42 0.00 0.00
April 30 4.16 6.12 10.28 3.82 6.45 6.45 0.00 6.45 0.00 0.00
May 31 6.97 6.32 13.29 5.84 7.45 7.45 0.00 7.45 0.00 0.00
June 30 9.80 6.12 15.92 6.97 8.95 8.95 0.00 8.95 0.00 0.00
July 31 11.62 6.32 17.95 8.59 9.36 9.36 0.00 9.36 0.00 0.00
August 31 10.05 6.32 16.37 10.36 6.02 6.02 0.00 6.02 0.00 0.00
September 30 7.07 6.12 13.19 10.59 2.60 2.60 0.00 2.60 0.00 0.00
October 31 4.12 6.32 10.44 5.94 4.50 4.50 0.00 4.50 0.00 0.00
November 30 1.91 6.12 8.03 4.40 3.63 3.63 0.00 3.63 0.00 0.00
December 31 0.98 6.32 7.31 4.58 2.73 2.73 0.00 2.73 0.00 0.00
Calcs.Calcs.Calc. M.A.I.Manual M.A.I.M.A.I. Used Calcs.
Totals:365 60.50 74.46 134.96 75.12 59.84 59.84 0.00 0.00
Maximum Monthly Storage Required for the Irrigation of Zone 2:
inches acres gallons
0.00 over 0.00 =0
Published soil permeability
rates by series or textural class
are not acceptable. Actual in-
situ soils Ksat data is required.In-situ saturated vertical
hydraulic conductivity
(Ksat)
Drainage
factor (f)
Soil
Drainage
Rate
FYI
Click the
"CALCULATE"
button after making
changes.
Zone 2 Description:Series Name
Calculate Soil Drainage
Water table depth
(BLS)
risk of
perching
Soils Series Information for Zone 2 Potential site limitations
Is bedrock <
60" BLS ?
Copied from Influent & Zones Setup Sheet:
HELPCummulative
Storage
Required for
Irrigation
Actual
Monthly
Irrigation Rate
DRGNCW20.426_Waterbalance_Wilm_FEB_2022 Z2 Version 5 December 2004
Soils and Water Balance for Zone 3
Drainage class BLS = below land surface
Step 1 Step 2 f x Ksat
in/hr in/day percent in/day
0.08 1.92 0.080 0.15 Daily Flow = 0 gals/day
Zone 3 Area = 0.00 acres
Zone 3 Zone 3
Calculated Manual
Override Actual Used
Month Days per
month PET
Zone 3
Soil
Drainage
Zone 3
Total
Loss
Precip
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Design Irrigation
per Month
Monthly
Excess
inches inches inches inches inches inches inches inches inches inches inches
January 31 0.72 4.76 5.48 4.71 0.77 0.00 0.00 0.00 0.00 0.00 0.00
February 28 0.98 4.30 5.28 4.30 0.98 0.00 0.00 0.00 0.00 0.00 0.00
March 31 2.11 4.76 6.87 5.01 1.85 1.85 0.00 1.85 0.00 0.00
April 30 4.16 4.61 8.77 3.82 4.94 4.94 0.00 4.94 0.00 0.00
May 31 6.97 4.76 11.73 5.84 5.89 5.89 0.00 5.89 0.00 0.00
June 30 9.80 4.61 14.41 6.97 7.44 7.44 0.00 7.44 0.00 0.00
July 31 11.62 4.76 16.39 8.59 7.80 7.80 0.00 7.80 0.00 0.00
August 31 10.05 4.76 14.81 10.36 4.46 4.46 0.00 4.46 0.00 0.00
September 30 7.07 4.61 11.68 10.59 1.09 1.09 0.00 1.09 0.00 0.00
October 31 4.12 4.76 8.88 5.94 2.94 2.94 0.00 2.94 0.00 0.00
November 30 1.91 4.61 6.52 4.40 2.12 2.12 0.00 2.12 0.00 0.00
December 31 0.98 4.76 5.74 4.58 1.17 0.00 0.00 0.00 0.00 0.00 0.00
Calcs.Calcs.Calc. M.A.I.Manual M.A.I.M.A.I. Used Calcs.
Totals:365 60.50 56.06 116.56 75.12 41.44 38.52 0.00 0.00
Maximum Monthly Storage Required for the Irrigation of Zone 3:
inches acres gallons
0.00 over 0.00 =0
FYI
Soils Series Information for Zone 3 Potential site limitations
Water table depth
(BLS)
risk of
perching
Is bedrock <
60" BLS ?Series Name
Published soil permeability
rates by series or textural class
are not acceptable. Actual in-
situ soils Ksat data is required.In-situ saturated vertical
hydraulic conductivity
(Ksat)
Drainage
factor (f)
Soil
Drainage
Rate
Zone 3 Description:
Calculate Soil Drainage
Copied from Influent & Zones Setup Sheet:
HELPCummulative
Storage
Required for
Irrigation
Actual
Monthly
Irrigation Rate
Click the
"CALCULATE"
button after making
changes.
DRGNCW20.426_Waterbalance_Wilm_FEB_2022 Z3 Version 5 December 2004
Soils and Water Balance for Zone 4
Drainage class BLS = below land surface
s poorly 1.5 - <2.0 low no
Step 1 Step 2 f x Ksat
in/hr in/day percent in/day
0.15 3.60 0.040 0.14 Daily Flow = 0 gals/day
Zone 4 Area = 0.00 acres
Zone 4 Zone 4
Calculated Manual
Override Actual Used
Month Days per
month PET
Zone 4
Soil
Drainage
Zone 4
Total
Loss
Precip
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Design Irrigation
per Month
Monthly
Excess
inches inches inches inches inches inches inches inches inches inches inches
January 31 0.72 4.46 5.19 4.71 0.47 0.00 0.00 0.00 0.00 0.00 0.00
February 28 0.98 4.03 5.01 4.30 0.71 0.71 0.00 0.71 0.00 0.00
March 31 2.11 4.46 6.57 5.01 1.56 1.56 0.00 1.56 0.00 0.00
April 30 4.16 4.32 8.48 3.82 4.65 4.65 0.00 4.65 0.00 0.00
May 31 6.97 4.46 11.43 5.84 5.59 5.59 0.00 5.59 0.00 0.00
June 30 9.80 4.32 14.12 6.97 7.15 7.15 0.00 7.15 0.00 0.00
July 31 11.62 4.46 16.09 8.59 7.50 7.50 0.00 7.50 0.00 0.00
August 31 10.05 4.46 14.51 10.36 4.16 4.16 0.00 4.16 0.00 0.00
September 30 7.07 4.32 11.39 10.59 0.80 0.80 0.00 0.80 0.00 0.00
October 31 4.12 4.46 8.58 5.94 2.64 2.64 0.00 2.64 0.00 0.00
November 30 1.91 4.32 6.23 4.40 1.83 1.83 0.00 1.83 0.00 0.00
December 31 0.98 4.46 5.45 4.58 0.87 0.00 0.00 0.00 0.00 0.00 0.00
Calcs.Calcs.Calc. M.A.I.Manual M.A.I.M.A.I. Used Calcs.
Totals:365 60.50 52.56 113.06 75.12 37.94 36.59 0.00 0.00
Maximum Monthly Storage Required for the Irrigation of Zone 4:
inches acres gallons
0.00 over 0.00 =0
FYI
Soils Series Information for Zone 4 Potential site limitations
Water table depth
(BLS)
risk of
perching
Is bedrock <
60" BLS ?Series Name
Published soil permeability
rates by series or textural class
are not acceptable. Actual in-
situ soils Ksat data is required.In-situ saturated vertical
hydraulic conductivity
(Ksat)
Drainage
factor (f)
Soil
Drainage
Rate
Zone 4 Description:
Calculate Soil Drainage Lynchburg
Copied from Influent & Zones Setup Sheet:
HELPCummulative
Storage
Required for
Irrigation
Actual
Monthly
Irrigation Rate
Click the
"CALCULATE"
button after making
changes.
DRGNCW20.426_Waterbalance_Wilm_FEB_2022 Z4 Version 5 December 2004
Soils and Water Balance for Zone 5
Drainage class BLS = below land surface
Step 1 Step 2 f x Ksat
in/hr in/day percent in/day
0.25 6.00 0.040 0.24 Daily Flow = 0 gals/day
Zone 5 Area = 0.00 acres
Zone 5 Zone 5
Calculated Manual
Override Actual Used
Month Days per
month PET
Zone 5
Soil
Drainage
Zone 5
Total
Loss
Precip
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Design Irrigation
per Month
Monthly
Excess
inches inches inches inches inches inches inches inches inches inches inches
January 31 0.72 7.44 8.16 4.71 3.45 3.45 0.00 3.45 0.00 0.00
February 28 0.98 6.72 7.70 4.30 3.40 3.40 0.00 3.40 0.00 0.00
March 31 2.11 7.44 9.55 5.01 4.53 4.53 0.00 4.53 0.00 0.00
April 30 4.16 7.20 11.36 3.82 7.53 7.53 0.00 7.53 0.00 0.00
May 31 6.97 7.44 14.41 5.84 8.57 8.57 0.00 8.57 0.00 0.00
June 30 9.80 7.20 17.00 6.97 10.03 10.03 0.00 10.03 0.00 0.00
July 31 11.62 7.44 19.06 8.59 10.48 10.48 0.00 10.48 0.00 0.00
August 31 10.05 7.44 17.49 10.36 7.13 7.13 0.00 7.13 0.00 0.00
September 30 7.07 7.20 14.27 10.59 3.68 3.68 0.00 3.68 0.00 0.00
October 31 4.12 7.44 11.56 5.94 5.61 5.61 0.00 5.61 0.00 0.00
November 30 1.91 7.20 9.11 4.40 4.71 4.71 0.00 4.71 0.00 0.00
December 31 0.98 7.44 8.42 4.58 3.85 3.85 0.00 3.85 0.00 0.00
Calcs.Calcs.Calc. M.A.I.Manual M.A.I.M.A.I. Used Calcs.
Totals:365 60.50 87.60 148.10 75.12 72.98 72.98 0.00 0.00
Maximum Monthly Storage Required for the Irrigation of Zone 5:
inches acres gallons
0.00 over 0.00 =0
FYI
Soils Series Information for Zone 5 Potential site limitations
Water table depth
(BLS)
risk of
perching
Is bedrock <
60" BLS ?Series Name
Published soil permeability
rates by series or textural class
are not acceptable. Actual in-
situ soils Ksat data is required.In-situ saturated vertical
hydraulic conductivity
(Ksat)
Drainage
factor (f)
Soil
Drainage
Rate
Zone 5 Description:
Calculate Soil Drainage
Copied from Influent & Zones Setup Sheet:
HELPCummulative
Storage
Required for
Irrigation
Actual
Monthly
Irrigation Rate
Click the
"CALCULATE"
button after making
changes.
DRGNCW20.426_Waterbalance_Wilm_FEB_2022 Z5 Version 5 December 2004
Soils and Water Balance for Zone 6
Drainage class BLS = below land surface
Step 1 Step 2 f x Ksat
in/hr in/day percent in/day
0.25 6.00 0.040 0.24 Daily Flow = 0 gals/day
Zone 6 Area = 0.00 acres
Zone 6 Zone 6
Calculated Manual
Override Actual Used
Month Days per
month PET
Zone 6
Soil
Drainage
Zone 6
Total
Loss
Precip
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Design Irrigation
per Month
Monthly
Excess
inches inches inches inches inches inches inches inches inches inches inches
January 31 0.72 7.44 8.16 4.71 3.45 3.45 0.00 3.45 0.00 0.00
February 28 0.98 6.72 7.70 4.30 3.40 3.40 0.00 3.40 0.00 0.00
March 31 2.11 7.44 9.55 5.01 4.53 4.53 0.00 4.53 0.00 0.00
April 30 4.16 7.20 11.36 3.82 7.53 7.53 0.00 7.53 0.00 0.00
May 31 6.97 7.44 14.41 5.84 8.57 8.57 0.00 8.57 0.00 0.00
June 30 9.80 7.20 17.00 6.97 10.03 10.03 0.00 10.03 0.00 0.00
July 31 11.62 7.44 19.06 8.59 10.48 10.48 0.00 10.48 0.00 0.00
August 31 10.05 7.44 17.49 10.36 7.13 7.13 0.00 7.13 0.00 0.00
September 30 7.07 7.20 14.27 10.59 3.68 3.68 0.00 3.68 0.00 0.00
October 31 4.12 7.44 11.56 5.94 5.61 5.61 0.00 5.61 0.00 0.00
November 30 1.91 7.20 9.11 4.40 4.71 4.71 0.00 4.71 0.00 0.00
December 31 0.98 7.44 8.42 4.58 3.85 3.85 0.00 3.85 0.00 0.00
Calcs.Calcs.Calc. M.A.I.Manual M.A.I.M.A.I. Used Calcs.
Totals:365 60.50 87.60 148.10 75.12 72.98 72.98 0.00 0.00
Maximum Monthly Storage Required for the Irrigation of Zone 6:
inches acres gallons
0.00 over 0.00 =0
FYI
Soils Series Information for Zone 6 Potential site limitations
Water table depth
(BLS)
risk of
perching
Is bedrock <
60" BLS ?Series Name
Published soil permeability
rates by series or textural class
are not acceptable. Actual in-
situ soils Ksat data is required.In-situ saturated vertical
hydraulic conductivity
(Ksat)
Drainage
factor (f)
Soil
Drainage
Rate
Zone 6 Description:
Calculate Soil Drainage
Copied from Influent & Zones Setup Sheet:
HELPCummulative
Storage
Required for
Irrigation
Actual
Monthly
Irrigation Rate
Click the
"CALCULATE"
button after making
changes.
DRGNCW20.426_Waterbalance_Wilm_FEB_2022 Z6 Version 5 December 2004
Soils and Water Balance for Zone 7
Drainage class BLS = below land surface
Step 1 Step 2 f x Ksat
in/hr in/day percent in/day
0.25 6.00 0.040 0.24 Daily Flow = 0 gals/day
Zone 7 Area = 0.00 acres
Zone 7 Zone 7
Calculated Manual
Override Actual Used
Month Days per
month PET
Zone 7
Soil
Drainage
Zone 7
Total
Loss
Precip
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Design Irrigation
per Month
Monthly
Excess
inches inches inches inches inches inches inches inches inches inches inches
January 31 0.72 7.44 8.16 4.71 3.45 3.45 0.00 3.45 0.00 0.00
February 28 0.98 6.72 7.70 4.30 3.40 3.40 0.00 3.40 0.00 0.00
March 31 2.11 7.44 9.55 5.01 4.53 4.53 0.00 4.53 0.00 0.00
April 30 4.16 7.20 11.36 3.82 7.53 7.53 0.00 7.53 0.00 0.00
May 31 6.97 7.44 14.41 5.84 8.57 8.57 0.00 8.57 0.00 0.00
June 30 9.80 7.20 17.00 6.97 10.03 10.03 0.00 10.03 0.00 0.00
July 31 11.62 7.44 19.06 8.59 10.48 10.48 0.00 10.48 0.00 0.00
August 31 10.05 7.44 17.49 10.36 7.13 7.13 0.00 7.13 0.00 0.00
September 30 7.07 7.20 14.27 10.59 3.68 3.68 0.00 3.68 0.00 0.00
October 31 4.12 7.44 11.56 5.94 5.61 5.61 0.00 5.61 0.00 0.00
November 30 1.91 7.20 9.11 4.40 4.71 4.71 0.00 4.71 0.00 0.00
December 31 0.98 7.44 8.42 4.58 3.85 3.85 0.00 3.85 0.00 0.00
Calcs.Calcs.Calc. M.A.I.Manual M.A.I.M.A.I. Used Calcs.
Totals:365 60.50 87.60 148.10 75.12 72.98 72.98 0.00 0.00
Maximum Monthly Storage Required for the Irrigation of Zone 7:
inches acres gallons
0.00 over 0.00 =0
FYI
Soils Series Information for Zone 7 Potential site limitations
Water table depth
(BLS)
risk of
perching
Is bedrock <
60" BLS ?Series Name
Published soil permeability
rates by series or textural class
are not acceptable. Actual in-
situ soils Ksat data is required.In-situ saturated vertical
hydraulic conductivity
(Ksat)
Drainage
factor (f)
Soil
Drainage
Rate
Zone 7 Description:
Calculate Soil Drainage
Copied from Influent & Zones Setup Sheet:
HELPCummulative
Storage
Required for
Irrigation
Actual
Monthly
Irrigation Rate
Click the
"CALCULATE"
button after making
changes.
DRGNCW20.426_Waterbalance_Wilm_FEB_2022 Z7 Version 5 December 2004
Soils and Water Balance for Zone 8
Drainage class BLS = below land surface
Step 1 Step 2 f x Ksat
in/hr in/day percent in/day
0.25 6.00 0.040 0.24 Daily Flow = 0 gals/day
Zone 8 Area = 0.00 acres
Zone 8 Zone 8
Calculated Manual
Override Actual Used
Month Days per
month PET
Zone 8
Soil
Drainage
Zone 8
Total
Loss
Precip
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Design Irrigation
per Month
Monthly
Excess
inches inches inches inches inches inches inches inches inches inches inches
January 31 0.72 7.44 8.16 4.71 3.45 3.45 0.00 3.45 0.00 0.00
February 28 0.98 6.72 7.70 4.30 3.40 3.40 0.00 3.40 0.00 0.00
March 31 2.11 7.44 9.55 5.01 4.53 4.53 0.00 4.53 0.00 0.00
April 30 4.16 7.20 11.36 3.82 7.53 7.53 0.00 7.53 0.00 0.00
May 31 6.97 7.44 14.41 5.84 8.57 8.57 0.00 8.57 0.00 0.00
June 30 9.80 7.20 17.00 6.97 10.03 10.03 0.00 10.03 0.00 0.00
July 31 11.62 7.44 19.06 8.59 10.48 10.48 0.00 10.48 0.00 0.00
August 31 10.05 7.44 17.49 10.36 7.13 7.13 0.00 7.13 0.00 0.00
September 30 7.07 7.20 14.27 10.59 3.68 3.68 0.00 3.68 0.00 0.00
October 31 4.12 7.44 11.56 5.94 5.61 5.61 0.00 5.61 0.00 0.00
November 30 1.91 7.20 9.11 4.40 4.71 4.71 0.00 4.71 0.00 0.00
December 31 0.98 7.44 8.42 4.58 3.85 3.85 0.00 3.85 0.00 0.00
Calcs.Calcs.Calc. M.A.I.Manual M.A.I.M.A.I. Used Calcs.
Totals:365 60.50 87.60 148.10 75.12 72.98 72.98 0.00 0.00
Maximum Monthly Storage Required for the Irrigation of Zone 8:
inches acres gallons
0.00 over 0.00 =0
FYI
Soils Series Information for Zone 8 Potential site limitations
Water table depth
(BLS)
risk of
perching
Is bedrock <
60" BLS ?Series Name
Published soil permeability
rates by series or textural class
are not acceptable. Actual in-
situ soils Ksat data is required.In-situ saturated vertical
hydraulic conductivity
(Ksat)
Drainage
factor (f)
Soil
Drainage
Rate
Zone 8 Description:
Calculate Soil Drainage
Copied from Influent & Zones Setup Sheet:
HELPCummulative
Storage
Required for
Irrigation
Actual
Monthly
Irrigation Rate
Click the
"CALCULATE"
button after making
changes.
DRGNCW20.426_Waterbalance_Wilm_FEB_2022 Z8 Version 5 December 2004
Soils and Water Balance for Zone 9
Drainage class BLS = below land surface
Step 1 Step 2 f x Ksat
in/hr in/day percent in/day
0.25 6.00 0.040 0.24 Daily Flow = 0 gals/day
Zone 9 Area = 0.00 acres
Zone 9 Zone 9
Calculated Manual
Override Actual Used
Month Days per
month PET
Zone 9
Soil
Drainage
Zone 9
Total
Loss
Precip
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Design Irrigation
per Month
Monthly
Excess
inches inches inches inches inches inches inches inches inches inches inches
January 31 0.72 7.44 8.16 4.71 3.45 3.45 0.00 3.45 0.00 0.00
February 28 0.98 6.72 7.70 4.30 3.40 3.40 0.00 3.40 0.00 0.00
March 31 2.11 7.44 9.55 5.01 4.53 4.53 0.00 4.53 0.00 0.00
April 30 4.16 7.20 11.36 3.82 7.53 7.53 0.00 7.53 0.00 0.00
May 31 6.97 7.44 14.41 5.84 8.57 8.57 0.00 8.57 0.00 0.00
June 30 9.80 7.20 17.00 6.97 10.03 10.03 0.00 10.03 0.00 0.00
July 31 11.62 7.44 19.06 8.59 10.48 10.48 0.00 10.48 0.00 0.00
August 31 10.05 7.44 17.49 10.36 7.13 7.13 0.00 7.13 0.00 0.00
September 30 7.07 7.20 14.27 10.59 3.68 3.68 0.00 3.68 0.00 0.00
October 31 4.12 7.44 11.56 5.94 5.61 5.61 0.00 5.61 0.00 0.00
November 30 1.91 7.20 9.11 4.40 4.71 4.71 0.00 4.71 0.00 0.00
December 31 0.98 7.44 8.42 4.58 3.85 3.85 0.00 3.85 0.00 0.00
Calcs.Calcs.Calc. M.A.I.Manual M.A.I.M.A.I. Used Calcs.
Totals:365 60.50 87.60 148.10 75.12 72.98 72.98 0.00 0.00
Maximum Monthly Storage Required for the Irrigation of Zone 9:
inches acres gallons
0.00 over 0.00 =0
FYI
Soils Series Information for Zone 9 Potential site limitations
Water table depth
(BLS)
risk of
perching
Is bedrock <
60" BLS ?Series Name
Published soil permeability
rates by series or textural class
are not acceptable. Actual in-
situ soils Ksat data is required.In-situ saturated vertical
hydraulic conductivity
(Ksat)
Drainage
factor (f)
Soil
Drainage
Rate
Zone 9 Description:
Calculate Soil Drainage
Copied from Influent & Zones Setup Sheet:
HELPCummulative
Storage
Required for
Irrigation
Actual
Monthly
Irrigation Rate
Click the
"CALCULATE"
button after making
changes.
DRGNCW20.426_Waterbalance_Wilm_FEB_2022 Z9 Version 5 December 2004
Soils and Water Balance for Zone 10
Drainage class BLS = below land surface
Step 1 Step 2 f x Ksat
in/hr in/day percent in/day
0.25 6.00 0.020 0.12 Daily Flow = 0 gals/day
Zone 10 Area = 0.00 acres
Zone 10 Zone 10
Calculated Manual
Override Actual Used
Month Days per
month PET
Zone 10
Soil
Drainage
Zone 10
Total
Loss
Precip
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Maximum
Allowable
Irrigation
Design Irrigation
per Month
Monthly
Excess
inches inches inches inches inches inches inches inches inches inches inches
January 31 0.72 3.72 4.44 4.71 0.00 0.00 0.00 0.00 0.00 0.00
February 28 0.98 3.36 4.34 4.30 0.04 0.04 0.00 0.04 0.00 0.00
March 31 2.11 3.72 5.83 5.01 0.81 0.81 0.00 0.81 0.00 0.00
April 30 4.16 3.60 7.76 3.82 3.93 3.93 0.00 3.93 0.00 0.00
May 31 6.97 3.72 10.69 5.84 4.85 4.85 0.00 4.85 0.00 0.00
June 30 9.80 3.60 13.40 6.97 6.43 6.43 0.00 6.43 0.00 0.00
July 31 11.62 3.72 15.34 8.59 6.76 6.76 0.00 6.76 0.00 0.00
August 31 10.05 3.72 13.77 10.36 3.41 3.41 0.00 3.41 0.00 0.00
September 30 7.07 3.60 10.67 10.59 0.08 0.08 0.00 0.08 0.00 0.00
October 31 4.12 3.72 7.84 5.94 1.89 1.89 0.00 1.89 0.00 0.00
November 30 1.91 3.60 5.51 4.40 1.11 1.11 0.00 1.11 0.00 0.00
December 31 0.98 3.72 4.70 4.58 0.13 0.13 0.00 0.13 0.00 0.00
Calcs.Calcs.Calc. M.A.I.Manual M.A.I.M.A.I. Used Calcs.
Totals:365 60.50 43.80 104.30 75.12 29.45 29.45 0.00 0.00
Maximum Monthly Storage Required for the Irrigation of Zone 10:
inches acres gallons
0.00 over 0.00 =0
FYI
Soils Series Information for Zone 10 Potential site limitations
Water table depth
(BLS)
risk of
perching
Is bedrock <
60" BLS ?Series Name
Published soil permeability
rates by series or textural class
are not acceptable. Actual in-
situ soils Ksat data is required.In-situ saturated vertical
hydraulic conductivity
(Ksat)
Drainage
factor (f)
Soil
Drainage
Rate
Zone 10 Description:
Calculate Soil Drainage
Copied from Influent & Zones Setup Sheet:
HELPCummulative
Storage
Required for
Irrigation
Actual
Monthly
Irrigation Rate
Click the
"CALCULATE"
button after making
changes.
DRGNCW20.426_Waterbalance_Wilm_FEB_2022 Z10 Version 5 December 2004
Zonal Storage Summations OBJECT: To calculate the minimum wet weather storage required for a multiple zoned spray irrigation site.
5,510 gpd 0 gpd 0 gpd 0 gpd 0 gpd 0 gpd 0 gpd 0 gpd 0 gpd 0 gpd
2.70 acres 0 acres 0 acres 0 acres 0 acres 0 acres 0 acres 0 acres 0 acres 0 acres Total Area
(acres) =2.70
Month
Days per
month
inches gallons inches gallons inches gallons inches gallons inches gallons inches gallons inches gallons inches gallons inches gallons inches gallons
January 31 0.34 24,907 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0
February 28 0.36 26,459 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0
March 31 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0
April 30 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0
May 31 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0
June 30 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0
July 31 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0
August 31 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0
September 30 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0
October 31 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0
November 30 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0
December 31 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0
Minimum Required Storage (gallons)
gpd = 4.8 days
0
0
Total Flow
Disposed
(gpd) =
5,510
Design Daily
Influent
(gpd) =
5,510
24,907
gallons
Cummulative Storage
Required
Cummulative Storage
Required
Zone Description =>>
Lynchburg
Daily Flow to Zone =>>
FYI Minimum Required
Storage
26,459
FYI
Totals
0
0
0
0
0
0
26,459
0
0
Zone 10Zone 4 Zone 5 Zone 6 Zone 7 Zone 8 Zone 9Zone 1 Zone 2 Zone 3
Predominant Soils =>>
Goldsboro
Rains
Wetted Acreage ==>>
Cummulative Storage
Required
Cummulative Storage
Required
Cummulative Storage
Required
Cummulative Storage
Required
Cummulative Storage
Required
Cummulative Storage
Required
Cummulative Storage
Required
Cummulative Storage
Required
Cummulative Storage
Required
Minimum Storage =26,459 5,510gallons divided by
DRGNCW20.426_Waterbalance_Wilm_FEB_2022 Zonal Sums Version 5 December 2004
Calculations:
Listed below are all the calculations used in the Spray Irrigation Water Balance Program, excluding the macros.
Note:
(Units are indicated in italics)
Precipitation Worksheet
Percent of Mean Annual Precipitation
example:
If the mean monthly precipitation for January is 5 inches , with a mean annual precipitation of 68 inches , then
80th Percentile Monthly Precipitation
example:
Please note, that the actual values stored and used in the water budget calculations are not rounded off to the number of decimal
figures actually displayed. Hand computations will vary from those displayed. The net output, in terms of storage requirements,
spray field areas, and hydraulic loading rates will not be significantly different, however.
Percent of Mean Annual Precipitation (unit-less ) = [Mean Monthly Rainfall (inches) divided by Mean Annual Rainfall
(inches)] times 100
the Percent of Mean Annual Precipitation for January
= [5 inches divided by 68 inches ] times 100
= .073529 times 100
= 7.35 percent
80th Percentile Monthly Precipitation (inches) = [Percent of Mean Annual Precipitation (unitless) divided by 100] times
80th Percentile Year Precipitation (inches)
if the Percent of Mean Annual Precipitation is 7.35 percent for January (continuing from above), and the 80th Percentile Year
Precipitation is 75 (inches), then the 80th Percentile Monthly Precipitation
= [ 7.3529 divided by 100] times 75 (inches)
= .073529 times 75 (inches)
= 5.51 (inches)
Potential Evapo-Transpiration Worksheet (Thornthwaite Method)
(note this is an empirically derived set of relationships)
Daylight Hours / 12 (a comparison between the average length of days by month)
Daylight Hours / 12 January = [ [[.87-0.9] / [35 (degrees) - 30 (degrees)]] times [Site Lattitude (degrees) - 30 (degrees)] ] + 0.9
Daylight Hours/ 12 February = [ [[.85-.87] / [35 (degrees) - 30 (degrees)]] times [Site Lattitude (degrees) - 30 (degrees)] ] + 0.87
Daylight Hours/12 March = [ [[1.03-1.03] / [35 (degrees) - 30 (degrees)]] times [Site Lattitude (degrees) - 30 (degrees)] ] + 1.03
Daylight Hours/ 12 April = [ [[1.09-1.08] / [35 (degrees) - 30 (degrees)]] times [Site Lattitude (degrees) - 30 (degrees)] ] + 1.08
Daylight Hours/ 12 May = [ [[1.21-1.18] / [35 (degrees) - 30 (degrees)]] times [Site Lattitude (degrees) - 30 (degrees)] ] + 1.18
Daylight Hours/ 12 June = [ [[1.21-.1.17] / [35 (degrees) - 30 (degrees)]] times [Site Lattitude (degrees) - 30 (degrees)] ] + 1.17
Daylight Hours/ 12 July = [ [[1.23-1.2] / [35 (degrees) - 30 (degrees)]] times [Site Lattitude (degrees) - 30 (degrees)] ] + 1.2
Daylight Hours/ 12 August = [ [[1.16-1.14] / [35 (degrees) - 30 (degrees)]] times [Site Lattitude (degrees) - 30 (degrees)] ] + 1.14
Daylight Hours/12 September = [ [[1.03-1.03] / [35 (degrees) - 30 (degrees)]] times [Site Lattitude (degrees) - 30 (degrees)] ] + 0.9
Daylight Hours/ 12 October = [ [[.97-.98] / [35 (degrees) - 30 (degrees)]] times [Site Lattitude (degrees) - 30 (degrees)] ] + 0.98
Daylight Hours/ 12 November = [ [[.86-.89] / [35 (degrees) - 30 (degrees)]] times [Site Lattitude (degrees) - 30 (degrees)] ] + 0.89
Daylight Hours/ 12 December = [ [[.85-.88] / [35 (degrees ) - 30 (degrees)]] times [Site Lattitude (degrees) - 30 (degrees)] ] + 0.88
* (degrees north lattitude)
example:
Heat Index
Heat index (degrees F) = [Mean Monthly Temperature (degrees F) -32 (degrees F) / 9] raised to the power of 1.514
example:
The heat index for January (location near 36 degrees lattitude)
=[43.5 (degrees F) - 32 (degrees F)/ 9]1.514
=[11.5 (degrees F)/ 9]1.514
=[1.2778 (degrees F)]1.514
=1.4494 (degrees F)
If the site to be used is located at 36.5 degrees (north lattitude), then the number of daylight hours / 12 for January
= [[[.87-.9] /[35 (degrees) - 30 (degrees)]] times [36.5 (degrees) - 30 (degrees)] +0.9,
= [[-.03 /5 (degrees)] times 6.5 (degrees)] + 0.9
= [-.006 times 6.5] + 0.9
= .861(unit less)
Calculated PET
example:
=.5418 (hours) times [[575 (degrees F) divided by 666.54 (degrees F)] raised to 1.67085274]
=.5418 (hours) times [.86266391 (degrees F) raised to 1.67085274]
=.5418 (hours) times .78126939
=.4234
Influent+Zones Setup Worksheet
Adjusted Pan Data
Adjusted Pan Data (inches) = Pan Evaporation Data (inches) times 70 percent
example:
Lagoon Losses
Lagoon Losses (gallons) = Adjusted Pan Data (inches) times Area of Lagoon (acres) times 27,152 (gallons per acre-inch)
example:
The Lagoon Losses in January with an adjusted pan of .91 (inches) and a lagoon 2 (acres) in size
=.5418 (hours) times [[[50 times 11.5 (degrees F)] divided by 666.54 (degrees F)] raised to[.27419207 (degrees F)- .42288453 (degrees F)
+ 1.3271552 +0.49239]]
The Adjusted Pan Data for January (inches)
= 1.3 (inches) times .70
= .91 (inches)
=[ .91 (inches) times 2 (acres)] times 27,152 (gallons per acre-inch)
= 1.82 (acre-inches) times 27,152 (gallons per acre-inch)
= 49,416.64 (gallons)
PET (inches)=[[0.63 times Daylight Hours / 12 (hours)] times [[[50 times [Mean Monthly Temperature (degrees F)-32 (degrees F)]]
divided by [9 times TOTAL Heat Index (degrees F)]] raised to [0.000000675 times [Total Heat Index 3(degrees F)]-0.0000771 times
[Total Heat Index 2(degrees F)]+ [0.01792 times TOTAL Heat Index (degrees F)] +0.49239]]]
The Calculated PET for January
= [[.63 times .86 (hours)] times [[[ 50 times [43.5 (degrees F)- 32 (degress F)]] divided by [ 9 times 74.06 (degress F)]] raised to
[.000000675 times 74.06 (degress F)] -[.0000771 times 74.06 (degrees F)] + [.01792 times 74.06 (degrees F)] +0.49239]]]
Lagoon Gains
Lagoon Gains (gallons) = Precipitation (inches) times Area of Lagoon (acres) times 27,152 (gallons per acre-inch)
example:
The Lagoon Gains in January with a precipitation of 4.71 (inches) and a lagoon 2 (acres) in size
Design Influent Volume per month
Design Influent Volume per month (gallons) = Design Daily Influent Volume (gallons per day) times Days per Month
example:
Total Volume to be Disposed
example:
= 310,000 ( gallons) - 49,417 (gallons) + 255,772 (gallons)
= 516,355 (gallons)

, (g )
=[4.71 (inches) times 2 (acres)] times 27,152 (gallons per acre-inch)
= 9.42 (acre-inches) times 27,152 (gallons per acre-inch)
= 255,771.84 (gallons)
= 10,000 (gallons per day) times 31 (days) January
= 310,000 (gallons)
Design Influent Volume per month (gallons) for January with a Design Daily Influent Volume of 10,000 (gallons per day)
Total Volume to be Disposed (gallons) = Design Influent Volume per month (gallons) - Lagoon Losses (gallons) + Lagoon Gains
(gallons)
Continuing with the three previous examples above, the Total Volume to be Disposed in January with an Design Daily Influent
Volume of 10,000 (gallons per day)
Design Irrigation per month (for a particular Zone)
example:
Assume: Zone 1 irrigates 7,000 gpd over 8 acres
Assume: Zone 2 irrigates 10,000 gpd over 15 acres
Total Volume disposed by Zone 1 = 7,000 gpd times 31 days (in January) = 217,000 gallons disposed in January
Total Volume disposed by Zone 2 = 10,000 gpd times 31 days (in January) = 310,000 gallons disposed in January
Hydraulic Loading Rates for Zone 1 = 217,000 gallons divided by 27,152 (gallons per acre-inch)] divided by 8 (acres)
Hydraulic Loading Rates for Zone 1 = 1.00 inches in January
Hydraulic Loading Rates for Zone 2 = 310,000 gallons divided by 27,152 (gallons per acre-inch)] divided by 15 (acres)
Hydraulic Loading Rates for Zone 2 = 0.76 inches in January
Zone 1 through Zone 10 Worksheets
In-situ Ksat
In-situ Ksat (inches per day) = In-situ Ksat (in per hour) times 12
Calculated Soil Drainage Rate
Calculated Soil Drainage Rate (inches per day) = In-situ Ksat (in per day) times [Soil Drainage Factor (unitless) divided by 100]
example:
The Calculated Soil Drainage Rate of a soil with a Ksat of 15 (inches per day) and a Soil Drainage Factor of 0.03
= 15 (inches per day) times 0.03
= .45 (inches per day)
Calculated Soil Drainage
Calculated Soil Drainage (inches) = Calculated Soil Drainage Rate (inches per day)) times Days Per Month
example:
Design Irrigation per month (inches) =[Volume to be Disposed (gallons) divided by 27,152 (gallons per acre-inch)] divided by the Area of
Spray Field (acres) for particular Zone
In this proceedure the Volume to be Disposed for each Zone is converted to an irrigation rate based on the application area
available.
The Calculated Soil Drainage of a soil with a Calculated Soil Drainage Rate of .45 (inches per day) in January
Total Loss
Total Loss (inches) = PET (inches) + Soil Drainage (inches)
example:
Maximum Allowable Irrigation
Maximum Allowable Irrigation (inches) = Total Loss (inches) - Precipitation (inches)
example:
Monthly Excess
Monthly Excess (inches) = Maximum Allowable Irrigation (inches) = Total Volume to be Disposed (inches)
example:
The Maximum Allowable Irrigation for the month of January (Mean Monthly Precipitation = 4.25 (inches))
= 14.37 (inches) - 4.25 (inches)
= 10.12 (inches)
The Monthly Excess for the month of January (Total Volume to be Disposed = .95 (inches))
= 10.12 (inches) - .95 (inches)
= 9.17 (inches)
The Total Loss for the month of January (Calculated PET =.42 (inches)) with a Calculated Soil Drainage of 13.95 (inches)
= .42 (inches) + 13.95 (inches)
= 14.37 (inches)
= .45 (inches per day) times 31 (days)
= 13.95 (inches)
Zonal Sums Worksheet
Cummulative Storage Required
example:
end_________
The Cummulative Storage Required conversion from inches to gallons for .25 (inches), over an application area of 20 (acres)
= [.25 (inches) times 20 (acres)] times 27,152 (gallons per acre-inch)
= 5 (acre-inches) times 27,152 (gallons per acre-inch)
= 135,760 (gallons)
This calculation converts the cummulative storage in inches from each Water Balance back to gallons, based on the specific
application area of each zone, so that a cummulative storage across all zones can be determined.
Cummulative Storage Required (gallons ) each zone = [Cummulative Storage Required (inches) times Area of Spray Field (acres)] times
27,152 (gallons per acre-inch)