20061223 Ver 3_Dffuse Flow mitigation doc_20230313

Tar -Pamlico Storm water Rule 15A NCAC 2B .025B
Last Modified 3/13/2023
Residential Worksheet when Footprints are not Shown
Use this ivorksheet Wier building footprints are not known to rleterruiue the acreage in each of the four categories -
transportation irtrper•vious, roof impervious, rrrarragedpervious, and ivoodedpervious - in the elevelopmerrt. You
will need these acreages for both tire "Export before BMPs" and "E.vport after BMPs" ►vorlislleets. For the
"Export after BMPs" ivorksheet, you will need to subtract the acreage occupied by BMPs frorrr the managed
pervious acreage produced by this workslreet. Also for the "Export after BMPs" ►vorksheet, if the development
contains more than one catchment, use this worksheet for each catchment.
Project Name: Brookstone Subdivision Phase 2
Date: 31112023
By: Univood Stroud
Directioirs:
> In the two green spaces in the box below, enter the average lot size and the percent of the right-of-way that is
impervious within the development.
> In the table below, for the type of land cover listed for each column, enter acreages in the green boxes beneath.
> In the "Lot Area" column, be sure to enter acreage within lots that is protected by a conservation easement, the Tar -
Pamlico buffer rule, or wetland rules in the green box in the lower lefthand corner (enter "0" if there is none). If lots
are drawn to exclude protected lands that are part of the total development acreage, enter the acreage of those protected
lands as wooded pervious in the "Community Areas" column.
> The spreadsheet will compute all values in the light blue shaded boxes.
> NOTE: In the "Community Areas" column, you will need to ensure that the various component acreages sum to the
value in the "TOTAL" box at the top. The spreadsheet will not correct for inconsistencies. Any inconsistency between
the total value and the sum of individual acreages will carry over to column (5).
Average lot size =W 0.29 ac (Must show building footprints if lot size < 0.13 ac.)
% impervious in right-of-way = %
-------------
-'= 1 $
g--iii
26.99
: Ti�a;iisji i fa io l irilnery au =
2.31
2.17
O.Q 4.48
)ooPi�iiti�ini€€
1.53
0.0 1.53
117ii1_pyors :`
10.60
1.14
1.42
13.16
.00
7.82
7.82

Tar -Pamlico Stormwater Rule 15A NCAC 2B .0258
Coastal Plain of the Tar -Pamlico River Basin:
Includes Greenville and Washington as well as Pitt and Beaufort Counties
Last Modified 3/13/2023
Total Nitrogen and Total Phosphorus Loading Calculation Work -Sheet (Automated)
Project Name: Brookstone Phase 2
Date: 31112023
By: LES Checked By:
Dkeetlons (saute for pi-e-development and post -development tables):
> Enter the acres of each type of land cover in the green boxes. The spreadsheet will calculate all of the values in light blue.
> Compare total areas of development in pre- and post- tables for consistency (bottom of column (2)), and also for consistency with
the site plans. If all of these values are not the same, there is an error that must be corrected.
> Unless drainage onto the development from offsite is diverted around or through the site, offsite catchment area draining in must
be included in the acreage values and treated.
Pre -development.
..0)..............................(21...................0 )...-...................(
.......-.................l...l..-.....-.........-.......}..-.....-...-......-...-t..l..........
A:ti�i'•�•�'�i�li���dluitiil�Ayi:''..
.'•��L�£�Eiliftitn
saeres
'i ariso#is+i'rtipi vii§`'
2.60
Q.19
1.95
0.11
== ttn$$?uci vivl8
1.42
0.28
= A i ged peruioii5 _
4.23
1.23
2.04
0.62
095
0.14
:=��t'�t•I_�1,¢r,.Ati�t±}�.$I01,II-
A.
,r1t,_,.-.,
Past -development:
�•:�`�c'tif`€Giitid�iiv� .....................tomI 't3ni"ilii;s�ve�`'�e•��6�I'��'suliihi<n:i:'•'�e"r''.`e••IkIC`:':�<"Iumn
•
.�►f'.'I`N:� m k, .:.
� - - 3 ..
.•a€:�1'!•iii'- =' :;
.
.. V1A$pq ij#'ii n m e v gjis ' : 2.54
2.60
29.54
0.19
2.16
:IMP 2.54
1.95
7,57
0.11
0.43
2.54
1.42
47.40
0.28
9.35
2.54
0.94
18.64
0.14
2.78
oiiixiti'eiwidU9::1 22
.. .....fl ...'
103.15
1frgAS�#1' g
'`1i1
14.71
26.99
j
3.82
S
0.54
Note: The nutrient loading goals are 4.0 lb/ac/yr for TN and 0.4 Ib/ac/yr for TP. If the post -development nutrient
loading is below these levels, then no BMP is necessary. Otherwise, the next worksheet calculates
post -development TN and TP loadings after BMPs are installed.

Tar -Pamlico Stormwater Rule 15A NCAC 2B .0258
Last Modified 5123103
Coastal Plain of the Tar -Pamlico River Basin:
Includes Greenville and Washinston as well as Pitt and Beaufort Counties
BMP Removal Calculation Worksheet (Automated)
Project Name: BrooksroneSubdivision
Date: 31112023
By: LES Checked By:
Directions.
> It maybe advantageous to split the development into separate catchments to be handled by separate
BMPs. The tables below allow
the development to be split into as many as three catchments, and can be copied for greater than three.
NOTE: Unless runoff flowing
onto the development from offsite is routed separately around or through the site, the offsita catchment area draining in must be
included in the acreage values of the appropriate land use(s) and treated.
> Above each table: Enter the catchment acreage in the top green blank. Based on a comparison of the
post -development TN and TP
export coefficients you calculated above to the rule requirements of4.0 lb/aclyr TN and 0.4 lblaclyr TP,
select BMP(s) from the list for
treating the catchment runoff. Enter the chosen BMP(s) nutrient removal rates in the green blanks. If
more than one BMP is to be
used in series, the combined removal rates will be calculated automatically in the blue blanks.
> Catchment Tables: Enter the acres of each type of land cover in the green boxes. The spreadsheet
will calculate all of the light blue
boxes. NOTE: Compare the Total Catchment Acreage for the Development (final table) to the value you established in the pre-BMP
worksheet tables, and also to the site plans, for consistency. All of these values need to be the same
................................................................................
........................ ............................
sET• €€:`I'1?€j€
..........................
�:esi`ri�f`tt at. .:.
BMP =' 1 c }ete t u aid 25 40
NC 13NIP Manual
NutrienttOtiiiNriirecSl'rtE iiii 40 35
NC BMP Manual
Removal -' i � r `= = i 35 45
NC BMP Manual
Rates Mft' == 35 45
NC BMP Manual
20 20
NC BMP Man ual
'e$el:tedIriCfertt;lji;sef'
20 35
NC BMP Manual
? l etci Ei¢is = 10 10
NC BMP Manual
Catchment 1:
Total acreage of catchment 1 = 19 J 6 ac
First BMP's TN removal rate = % First BMP's TP removal rate =
%
Second BMP's TN removal rate = % Second BMP's TP removal rate -
%
Third BMP's TN removal rate - % Third BMP's TP removal rate =
%
TOTAL TN REMOVAL RATE = 25 % TOTAL TP REMOVAL RATE =
40
...... �,.�.........:...E.::iiiiiiiiii
iiciiiii��cii�ii............�..?....-......_6..-..-{.-;!..._.-..._...._:..-...�,.�_..._.,....-.,.,.,:i��iiei,.,.
,.,.,.,.{•.�•.,.,..e
YPe{� I n�I.CzQYQr
AlEI1�lOt ,�i,l� I'V4'�PTII9
.Plea A lyl'
'41k1a4r1i
s2Cr'� e �'I
41315!ii _
grr.afi0WXWyei 10iis
3.36
2.60
39.19
0.11
2.86
3.36
1.95
10.04
0.11
0.57
: i4liitilii;etl p.et o]Est
3,36
1,42
56.09
0.28
11.06
oiidedjcyious'
3.36
0.94
0.00
0.14
0.00
i(i?ta iiby'$j►t'
3.36
1.95
9.25
0.11
0.52
.---.I!•tAeYiOtiTtti'Ert'iaii'S�1�=��
0.31
Ei il?[&Bll c
Ott
114.57
-
15.01
€IFrc=�3lfC''Civ
_�hII'TI►
. �`-.•fil,,kkat� uC�a•.n d�3i?cuf:,..._:
19.15
- ::::•:�:•
5.98
�''��1�
0.78
P
85.92
9.01
.::: Galizk.�.bfyrk.::
Di
st>it
Pk
:S'"Pt>IBTI
........
.
4.48
........ .
OA7

Tar -Pamlico StormwaterRule 15A NCAG 28.0258
Last Modifted 5123103
Catchment 2:
Total acreage of catchment 2 = ac
First BMP's TN removal rate - % First BMP's TP removal rate -=%
Second BMP's TN removal rate = % Second BMP's TP removal rate - %
Third BMP's TN removal rate = % Third BMP's TP removal rate = %
TOTAL TN REMOVAL RATE - 0 % TOTAL TP REMOVAL RATE = 0 %
aw" :::::
2O,,
Undiwa:::!
r A" wi",
im
0.51
2.60
0.00
0.19
0.00
0.51
1.95
0.00
0.11
0.00
0.51
1.42
0.00
0.28
0.00
0.51
0.94
3.75
0.14
0.56
Y.: 0)
0.51
1.95
0.00
0.11
0.00
•
mi 0::":!:
3.75
0.56
M. Wy
ff
..........
?N'
0.07
t oovi6 t
7.83
0.48
3.75
0.56
............
0.48
0.07
GI
Catchment 3:
Total acreage ofeatchment 3 - ac
First BMP's TN removal rate = % First BMP's TP removal rate %
Second BMP's TN removal rate = % Second BMP's TP removal rate = %
Third BMP's TN removal rate % Third BMP's TP removal rate = %
TOTAL TN REMOVAL RATE = 0 % TOTAL TP REMOVAL RATE %
:7W
VITA C:::. I 4, 4i:
2.60
@.19
-.1"i
1.95
0.11
1.42
0.28
jVaadedpi?v.vus0.94
0.14
1.95
0.11
'D �1 404 CV
!It
po

Tar -Pamlico Stofinwater Rule 15A NCAC 2B.0258
Last Modified 6/23103
Weighted Average ofNittrientLoadings from the Catchments:
..........
A �q]WUAW:: :.T:l :No '7!-'
19.16 4.48 0.47
7.83 0.48 0.07
0.00 0.00 0.00
26.99 3.32 0.35
Note: The nutrient loading goals are 4.0 lb/aclyr for TN and 0.4 lb/ae/yr for TP. If the post -development nutrient
loading is below these levels, then the BMPs planned are adequate. Otherwise, additional BMPs and/or
modifications in development plans are required,