NC0020231_SPECULATIVE LIMITS_19960118

NPDES DOCUMENT SCANNING COVER SHEET
NPDES Permit:
NC0020231
Louisburg WWTP
Document Type:
Permit Issuance
Wasteload Allocation
Authorization to Construct (AtC)
Permit Modification
Complete File - Historical
Data Monitoring Report
Speculative Limits
Instream Assessment (67b)
Environmental Assessment (EA)
Permit
History
Document Date:
January 18, 1996
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State -of North Carolina
Department of Environment,
Health and Natural Resources
Division of Environmental Management
James B. Hunt, Jr., Governor
Jonathan B.. Howes, Secretary
A. Preston Howard, Jr., P.E., Director
January 18, 1996
Ai'•'AN
�EHNR
Mr. Timothy J. Baldwin, P.E.
McKim & Creed Engineers, P.A.
5625 Dillard Rd., Bldg #1, Ste #117
.::Cary,-NC.._2751-1 - .� �_..—�_.�. Al, ,�-- - - - -, ... _._._ r..
__.
Subject: Water Treatment Plant Expansion
Impacts on Stream -Flow
Town of Louisburg
Franklin County
Dear Mr. Baldwin:
Thank you for the opportunity to evaluate and comment on your environmental review
of the expansion of the Louisburg Water Treatment Plant (WTP). The increased WTP
withdrawal, from 2.0 to 3.0 MGD, is likely to have significant implications with regard to
the critical low flow (7Q10) and available assimilative capacity for the downstream
discharge from the Town of Louisburg's wastewater treatment plant (WWI?);' The
implications of any stream flow reduction in,this area of the Tar River are complicated by
the fact that recent stream flow estimates from the U.S. Geological Survey have yielded a
7Q10 flow significafitly lower than previous estimates: The following is a more detailed
discussion of these concerns.
The current permit limits for the Louisburg WWTP were assigned in a 1991 wasteload
allocation based on a 7Q10 flow of 14 cfs at the discharge point. The flow was a 1986
U.S. Geological Survey (USGS) estimate based on flows from similar gauging stations in
the Tar Basin. A more recent (1994) and accurate USGS estimate based on actual flow
records collected at the gauging station at U.S. Highway 401 yielded a 7Q10 flow of-10.3
cfs at the discharge point. The Division has more confidence in the newer 7Q10 estimate
because it is based on flow records collected in the immediate area of the discharge which
were analyzed by the most recent statistical methodology.
The current Louisburg WWTP permit has summer limits of CBOD5 = 8.0 mg/l and
NH3N = 3.0 mg/l, but the facility is extremely well designed and operated, and it
consistently performs to levels indicative of advanced tertiary treatment (CBOD5 = 4.0 mg/1
and NH3N = 2.0 mg/l). The Division's most recent modeling analysis has shown that
when the lower 7Q10 flow of 10.3 cfs is used in the model, with current permitted
pollutant concentrations, the predicted downstream dissolved oxygen (DO) level falls
below the state water quality standard of 5.0 mg/l, to 4.4 mg/l. Self -monitoring instream
data from the facility has shown occasional violations of the DO standard downstream of
the discharge during each of the last two warm seasons, with DO levels falling as low as
3.6 mg/l in 1995. Hence, available instream data support the predictions of the modeling
analysis.
P.O. Box 29535, Raleigh, North Carolina 27626-0535 Telephone [phone] FAX [phone]
An Equal Opportunity Affirmative Action Employer 50% recycled/ 10% post -consumer paper

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=' Our modeling efforts have also shown that,, even .when the discharge is treated to the
tertiary treatment levels given above, a minimum stream flow of 9.0 cfs is required at the.
outfall point to insure adequate assimilative capacity and prevent predicted violations of the
DO standard. Increasing the withdrawal of the water treatment plant upstream of the
discharge from 2.0 to 3.0 MGD will increase the likelihood that flows at the discharge -
point will fall below 9.0 cfs and potentially cause more -frequent and severe DO violations
instream.
According to the Tar River basinwide management schedule, the NPDES permit for
the -Louisburg WWTP comes up for renewal in January -of the year 2000. If persistent low
DO levels continue to be recorded in this area -of the Tar River (which can be attributed to
_ the discharge} the Division may assign more stringentlimits for oxygen demanding_wastes_
'- -� upon�subsequent-NPpES-pertnit°renewalHowever;:the:Division1s:hopefulithaysuch
problems can be mitigated through continued optimizadon4of treatment at
through implementation of a minimum downstream flow provision with the planned
expansion of the water treatment plant. The agreement should provide for a reduction of
withdrawal as flows at the USGS gauge at Highway 401 approach 9.0 cfs with no _
withdrawal- above the existing 2.0 MGD if flows at the gauge are at 9.0 cfs or less.
Thank you again for the opportunity to comment and provide input in this matter. If
you have any questions please contact Jason -Doll of my staff at [phone] ext. 507.
Sincerely
Steve W. Tedder, Chief
Water Quality Section
C.L. Gobble - Town of Louisburg
Raleigh Regional Office
Coleen Sullins - Permits & Engineering
John D. Sutherland - Division of Water Resources
Jun Mead - Division of Water Resources
Central Files

State of North Carolina
Department of Environment,
Health and Natural Resources
Division of Wafter Resources
James B. Hunt, Jr., Governor
Jonathan B. Howes, Secretary
John N. Morris, Director
January 3, 1996
Mr. Timothy J. Baldwin, P.E.
McKim & Creed
Building 1, Suite 117
5625 Dillard Road
Cary, North Carolina'27511
Dear Mr. Baldwin:
A14rro
IDEHNR
I am responding to your letter dated December 20, 1995
requesting our review of information on the proposed renovation and
expansion of the Louisburg Water Treatment Plant.
We reviewed this information and have the following comments:
1. The paragraph at the top of page 2 is an accurate summary of
the results of our instream flow study of the Tar River.
2. We would recommend that the last sentence of the top paragraph
be replaced by the following paragraph to reflect the minimum
flows required to maintain the existing wastewater treatment
plant limits:
"Expanding the capacity of the water treatment plant by 1.0 MGD
will require that a minimum flow of between 9.0 and 11.5 cubic
feet per second (cfs) be maintained at the USGS gage downstream of
U.S. Highway 401. The 11.5 cfs flow maintains the existing
"compliance cushion" for the wastewater treatment plant, while the
9.0 cfs flow is the minimum flow for compliance under existing
plant limits. A minimum flow in the range from 9.0 to 11.5 cfs
will be sd ected by the Town and stipulated in the final EA for the
water treatment plant expansion. This minimum flow requirement
means that when natural flows in the Tar River drop below the
stipulated minimum at the USGS gage, the Town will reduce its
withdrawal. The reduction will be an amount that either results in
gage reading at the minimum flow or to 2.0 MGD, whichever is the
greater amount."
Sincerely yours,
John D. Sutherland, Chief
Water Resources Planning Section
cc: Mr. Jim Mead Woody Yonts
P.O. Box 27687, Raleigh, North Carolina 27611-7687 Telephone [phone]
An Equal Opportunity Affirmative Action Employer 60% recycled/ 10% post -consumer paper

•
IL.sJ=�
22 1995;
M, CIQ"&CF= 4
December 20, 1995 M&C 0245-0004.OR
ENGINEERS Mr. Steve Tedder'
North Carolina DEHNR P
SURVEYORS Division of Environmental Management
Water Quality Sectionjj
ARCHITECTS P.O. Box 27687
PLANNERS Raleigh, North Carolina 27611
Dear Mr. Tedder:
SUITE 117
BUILDING 1
5625 MLARD ROAD
CARY. NC 27511
PHONE [phone]
FAX [phone]
Enclosed is a copy of the letter that has been sent to elicit comments from the
agencies concerned with the Louisburg Water Treatment Plant Renovation and
Expansion project. Jason Doll was involved in the Tar River Instream Flow Study
referred to in the letter. Due to your agency's involvement with this study, we would
appreciate your review of the information contained in this letter. If you feel that any
information has been misrepresented or is absent, please respond with a listing of
your concerns.
Sincerely;
MCKIM & CREED ENGINEERS, P.A.
Timothy J. B wi XE.
Project Manager
Attachment

ENGINEERS
SURVEYORS
ARCHITECTS
PLANNERS
SUITE 117
BUILDING 1
5625 DILIARD ROAD
CARY. NC 27511
PHONE [phone]
FAX [phone]
Mq<T\4&CREED
December 20, 1995
Mr. Steve Tedder
Division of Environmental Management
Water Quality Section
P.O. Box 27687
Raleigh, North Carolina 27611
RE: Louisburg Water Treatment Plant Expansion
Environmental Review
Dear Mr. Tedder:
M&C 0245-0004.OR(10)
McKim & Creed Engineers is conducting a study on the expansion of the Louisburg Water
Treatment Plant as requested by the Town of Louisburg and Franklin County. We would
appreciate any comments that will help to insure that the environmental impact of the
expansion is minimal. Below is a brief description of the project.
Background Information
The City of Louisburg, North Carolina operates a municipal water treatment facility on the
banks of the Tar River in Franklin County. The existing facility provides treated water to the
incorporated community, as well as to unincorporated areas of Franklin County. The flow
demands of growth in both areas has put capacity pressures on the existing facility.
The plant is currently rated at 2.0 MGD capacity. The Town of Louisburg and Franklin
County are currentiy investigating the potential rehaLjilitation and upgrade of their existing
water treatment plant from 2.0 MGD to 3.0 MGD capacity.
Raw Water intake Issues
On December 20, 1994, Franklin County requested that the Division of Water Resources
(DWR) perform an in -stream flow study on the Tar River to determine the impact of an
additional 1.0 MGD withdrawal at the Louisburg Water Treatment Plant. The DWR, with
the assistance of the North Carolina Wildlife Resources Commission conducted the in -
stream flow study. The study was completed and the results transmitted to the County on
November 21, 1995. A meeting was held on November 28, 1995, with representatives of
DWR, WRC, and DEM to review the results of the study.
0 A024510004%104EAREV. RG

December 20, 1995
Page 2
From a critical habitat preservation standpoint, the study indicated that an additional 1.0
MGD run of river withdrawal would not have a statistically significant effect. However, this
withdrawal without a minimum release requirement, could affect the assimilative capacity
of the stream, and therefore the discharge permit limits at the next renewal for the Town's
Wastewater Treatment Plant discharge. While the plant may continue to take the current
capacity of 2.0 MGD, it will restrict the amount of increased withdrawal during low flow
periods to preserve this assimilative capacity.
Rehabilitation and Upgrade of Existing Facilities
Description of Existing Water Treatment Plant
The water treatment plant was designed in 1980 and began operation in 1982. The plant
is located on a very congested site, on a low bluff to the east of the river intake. To the
southeast, the facility is bordered by fenced residential property. To the west, expansion
is limited by the public works yard, CP&L, and the transfer/standby power station. The only
area immediately available for potential expansion is the grassy slope to the north of the
existing plant building. The available area appears to be approximately 170 feet x 224 feet
with about 15 feet in elevation relief running diagonally due north across the yard.
The treatment process employed by the Louisburg Water Treatment Plant is conventional
by most standards. Raw water from the river is pumped through a raw water meter to a
traditional flash mix chamber. A chemical coagulant and a synthetic polymer are added to
remove color, suspended solids, and any entrained algae or plant growth. After going
through the flash mix chamber, the water and added chemicals flow through a horizontal,
baffled flocculation channel. The flow then goes into a transitional entry channel prior to
two parallel rectangular sedimentation basins. Each basin line is followed by a single dual
media, rapid gravity sand filter. The water is chlorinated after filtration, and transferred to
finished water storage tanks (clearwells) to the north of the treatment plant structure. High
service pumps deliver finished water to the distribution system.
Rehabilitation and Expansion Components:
In order to reach a 3.0 MGD capacity, the existing plant must be rehabilitated and
expanded. The following is a list of the items required:
1. Raw Water Transfer Pumps
2. New Sedimentation Basin
3. Rehabilitation of Existing Sedimentation Basins
4. Two Additional Filters
5. Rehabilitation of the Two Existing Filters
6. Rehabilitate/Replace Chemical Systems
Q:50245104041101EAR EV. RG 40MC1Q"&CFXM

December 20, 1995
Page 3
7. Rehabilitate/Replace Mixing and Flocculation Systems
8. Chloramination Station
9. Sludge Handling Facilities
10, Piping
11. Electrical Systems and Instrumentation
All of these improvements are confined to the existing, previously disturbed site. The raw
water transfer pump station, located at the river, will be upgraded without the addition of
new structures or significant land disturbing activity. No work in or adjacent to the river
itself is planned.
I look forward to receiving your comments, which will be incorporated and addressed in the
Environmental Assessment document, scheduled to be prepared in January, 1996. Thank
you for working with McKim & Creed to reduce the environmental impacts of this project.
Sincerely.
MCKIM & CREED ENGINEERS, P.A.
TimothY J. dv�fn, P.E.
Project Manager
Attachment
Q',1024550004N 04EAREV.RG 40

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1Nd�d iNlAiVlai biivm s?Jn8smo�

State of Norl-h Carolina
Department of Environment,
Health and Natural Resources 4
Division of Wafter Resources
NlE
James B. Jr., Governor � C
dft, L�)��011111111L
Jcr,cthan B. B. Howes, Secretary C
John N. Morris, Director
November 21, 1995
MEMORANDUM
TO: Owen Anderson and John Alderman, Wildlife Resources Commission
Steve Reed, John Sutherland, and Jeff McMahon, Division of Water Resources
Jason Doll, Division of Environmental Management
Tim Baldwin, McKim and Creed
C.L. Gobble, Town of Louisburg
FROM: Jim Mead
SUBJECT: Results of Tar River Instream Flow Study
The Division of Water Resources (DWR) has completed the modeling and habitat time series
analysis for the Tar River instream flow study site. This memorandum summarizes the study and
presents the results for discussion and determination of the final flow recommendation.
Field Study:
In January of 1995, staff from DWR and the Wildlife Resources Commission (WRC) canoed a
nine mile segment of the Tar River between the Louisburg intake weir and a point one-half mile
above the confluence with Cedar Creek. Habitat types were mapped with observations every 5
minutes. The river is predominantly runs and pools with sand subs�rate, with cover consisting of
woody debris and root wads. A study site was selected just upstream of the Louisburg WWTP
discharge and downstream of Fox Creek. It is downstream of the water supply intake which
Louisburg has proposed expanding from a capacity of 2.0 mgd to 3.0 mgd.
Data collection began in May and was completed in August of 1995. The USGS gage at
Highway 401 was used to monitor flows, along with discharge measurements of Fox Creek
during each site visit. Data were collected at flows of 26, 69, and 245 cubic feet per second (cfs).
The bottom profile, water surface elevation versus discharge relationship, point velocities,
substrate, and cover were observed at each of six cross -sections. The habitat type and percentage
weighting for each of these is listed below.
P.O. Box 27687, Raleigh, North Carolina 27611-7687 Telephone [phone]
An Equal Opportunity Affirmative Action Employer W% recycled/ 1 Q% post -consumer paper

Tra� Habitat Tvae Percentage Weighting
1 gravel bar 10%
2 shallow run 10%
3 run with snags 20%
4 run with deep spot 20%
5 pool, moderated depth 30%
6 deep pool 10%
Physical Habitat Modelling
The methodology used to evaluate stream flows and aquatic habitat at this site is a series of
models and procedures referred to as the Instream Flow Incremental Methodology (IFIM). The
first step in analyzing the field data is to develop and calibrate an hydraulic model which predicts
depths and velocities for a range of flows at every point surveyed on each of the six transects.
A log -log stage -discharge relationship was used to predict water surface elevations (from which
point depths are determined) at transects 1, 4, 5, and 6. A model which uses mannings equation
was used to predict water elevations at transects 2 and 3. This latter approach was used to
improve the velocity simulations for these two transects, which were more difficult to model than
the other four.
The stream flow records for the gage at Highway 401 were examined to select a set of flows for
the hydraulic simulation "production runs." One model, based on velocities observed at 26 cfs,
was used to simulate conditions at flows ranging from 6 to 69 cfs. The other model, based on
velocities observed at 69 cfs, was used to simulate conditions at flows ranging from 26 to 650 cfs.
The next step in the IFIM procedure involves merging the simulated physical conditions with
habitat preference information for each life stage of each of the species being evaluated. Based on
discussions with WRC, the selected species were redbreast sunfish, creek chub, and the Tar River
Spiny Mussel. Habitat preference input for the two fish species was developed from information
published by the U.S. Fish and Wildlife Service (USFWS). The habitat preference criteria for
mussels were based on field data collected by WRC and DWR staff, with further analysis
performed by DWR following USFWS procedures. These are described in more detail in a DWR
memorandum dated October 12, 1995.
When the simulated physical conditions are merged with habitat preference input, the result is a
habitat versus flow relationship for each life stage of each species. A graph of this relationship for
the spiny mussel is attached. It should be noted that the spiny mussel habitat relationship was
determined using the physical conditions at transects 1 and 2 only. Research into mussel habitat
and stream flow has indicated that IFIM predictions for mussels should focus only on the habitat
types where they would be likely to occur.
2

Habitat Time Series -An alysis
The final analytical step in an IFIM study is referred to as a "time series analysis." This involves
merging a record of stream flows for the site in question with the habitat versus flow relationships
to yield a record of the habitat available over time for each species. This habitat record can then
be analyzed to determine target amounts of habitat which should be maintained to prevent
significant impacts. Additionally, records of "with project" stream flows and habitat availability
can be generated to compare different scenarios to the pre -project baseline conditions.
For the Tar River site, DWR used a record of daily flows from the gage at Highway 401 (USGS
station 02081747) for the period beginning in October of 1973 and ending in December of 1992.
The gage is located downstream from the Louisburg intake, so 0.5 mgd was added back to each
daily flow to approximate natural inflow to this river segment. The gage record was purposely
limited to this period to avoid the increased withdrawal attributed to the Novo plant. Also, the
daily flows were ratioed by drainage area from the gage (427 square miles) to the study site (437
square miI:;s) to reflect intervening inflow. This record of pre -project flows was then converted
to record of baseline habitat'for each species.
The pre -project flow record was modified to generate different with -project flow and habitat
scenarios. The first scenario involved a constant withdrawal of 3.0 mgd "skimmed" from the pre -
project flow record without any restrictions. If inflow was less than 3.0 mgd, then all of the
available flow was withdrawn and downstream flows were zero. This scenario was compared to
baseline conditions using a statistic referred to as "habitat index C," which is an average of the
lower 50% of the daily habitat values, by month. The assumption behind this approach is that the
species being considered are more influenced by stressful conditions, and cannot respond
positively to occasional higher amounts of habitat being available.
A review of the effect of the 3.0 mgd withdrawal scenario on habitat index C for all life stages of
all species indicated that the greatest impacts were on habitat available for the Tar River Spiny
Mussel. DWR therefore limited the evaluation of other scenarios to this species. A constant,
unrestricted withdrawal of 2.0 mgd was modeled to evaluate the habitat effects under the existing
rnaximi,m intake capacity. A third scenario, referred to as "alternative #1," was also modeled.
This involved a constant withdrawal of 2.0 mgd, with additional withdrawals up to a total of 3.0
mgd permitted as long as a minimum flow of 11.5 cfs was maintained below the intake.
The attached bar graph compares the effect of the different withdrawal scenarios in comparison to
baseline habitat index C for the spiny mussel. The largest impact is a 10% loss which occurs
during July and September under both the 3.0 mgd and the alternative #1 scenarios. Because of
the relatively small difference in withdrawal, and the infrequent occurrence of such low flows, the
3.0 mgd and Alternative #1 scenarios have virtually the same effect on downstream flows and
habitat. However, alternative #1 does ensure that the 7Q10 flow for assimilation of the WWTP
discharge is maintained.
3

Water Supply Availability
Additional analysis was performed to compare the frequency and amount of water supply
available under the 3.0 mgd and alternative #1 scenarios. This used the same gage record as the
habitat time series analysis, with 0.5 mgd added back to create a record of natural inflows before
the withdrawals. The gage is very close to the intake, so no conversion for drainage area was
necessary.
Using this record of available inflow, DWR analyzed the frequency of water supply availability for
the summer months and on an annual basis. The results are shown on the attached duration
curves. This analysis indicates that 3.0 mgd is always available for withdrawal if there are no
restrictions, ie. inflows are always greater than or equal to 3.0 mgd. Alternative #1 results -in a
slight reduction in the availability of the full 3.0 mgd withdrawal. For the worst case summer
months, the full 3.0 mgd is still available 96% of the time under alternative #1 restrictions.
Another way to look at this is that under alternative # 1, the Town would have to reduce their
withdrawal by up -to 1.0 mgd (but sometimes less) for about.5 days during the period from Jul;
through October.
Conclusion
A meeting has been scheduled for Tuesday, November 28th at 3:15 PM in the 11th floor
conference room of the Archdale Building in Raleigh. DWR has provided the results of these
analyses of habitat and water supply availability to all of the interested parties so that they can be
discussed further at this meeting. Hopefully, the issue of expanding Louisburg's intake from 2.0
to 3.0 mgd can be resolved at this meeting or very shortly thereafter. Please contact Jim Mead at
919/715-5428 if you have any questions.
4

TAR R. BELOW LOUISBURG WATER INTAKE
SPINY MUSSEL HABITAT vs FLOW
WUA (sq ft per 1000' of stream)
6,000
5,000
4,000
3,000
2,000
1,000
0
0 50 100 150 200 250 300 350 400 450 500 550 600 650
DISCHARGE (Cfs)
USED TR1 AND TR2 ONLY

6%
0%
-5%
-10%
TAR RIVER BELOW LOUISBURG INTAKE
TAR RIVER SPINEY MUSSEL
CHANGE IN HABITAT INDEX C
E
ME
JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
EM2 MGD =3 MGD ME ALT. #1
INDEX C - AVERAGE OF LOWER 50% OF EVENTS
% CHANGE - (PROJECT-NATURAL}/NATURAL
ALT 1- 2 MGD, PLUS 3 MGD IF 11.5 MINFLOW

TAR RIVER
WATER SUPPLY AVAILABLE
DURATION FOR JULY THROUGH OCTOBER
% OF TIME EQUALLED OR EXCEEDED
100%
99%
98%
97%
96%
95% —t
0
s
0.5 1 1.5 2 2.5 3 3.5
WATER SUPPLY AVAILABLE (MGD)
PROPOSED 3 MGD ALTERNATIVE #1
PROPOSED - 3.0 MGD, NO RESTRICTIONS
ALT.#1 - BETWEEN 2 AND 3 MGD WITHDRAWN
ONLY 1F 7Q10 FLOW —BY MAINTAINED
4 4.5 5

100%
99.5%
99%
98.5%
98%
TAR RIVER
WATER SUPPLY AVAILABLE
ANNUAL DURATION
% OF TIME EQUALLED OR EXCEEDED
0 0.5 1 1.5 2 2.5 3 3.5
WATER SUPPLY AVAILABLE (MGD)
-PROPOSED 3 MGD ------ ALTERNATIVE #1
PROPOSED - 3.0 MGD, NO RESTRICTIONS
ALT.#1 - BETWEEN 2 AND 3 MGD WITHDRAWN
ONLY IF 7Q10 FLOW -BY MAINTAINED
i
4 4.5 5

BOD5/NH3N = 5/2
7Q10 = 9.0 CFS
---------- MODEL RESULTS ----------
Discharger : LOUISBURG WWTP
Receiving Strum : TAR DIVER
----------------------------------------------------------------------
The End D.O. is 5.35 mg/l.
The End CBOD is 0.83 mg/1.
The End NBOD is 0.25 mg/l.
----------------------------------------------------------------------
WLA
WLA
WLA
DO Min CBOD
NBOO
00
Waste Flaw
(mg/1) Milepaint Reach # (mg/1)
(mg/1)
(mg/1)
(rngd)
Segment
1
5.04 4.80 3
Reach
1
7.50
9.00
5.00
1.37000
Reach
2
0.00
0.00
0.00
0.00000
Reach
3
0.00
0.00
0.00
0.00000
Reach
4
0.00
0.00
0.00
0.00000

oummtK
BOD5/NH3N
=
5/2
7Q10
= 9.5
CFS
----------
MODEL RESULTS -- -------
Discharger
:
LOUISBURG
WWTP
Receiving Stream
:
TAR RIVER
The End D.O.
is 5.42
mg/l.
The End CBOD
is 0.85
mg/l.
The End NBOD
----------------------------------------------------------------------
is 0.26
my/I.
WLA
WLA
WLA
DO Min
CBOD
NBOO
DO
Waste Flow
(mg/1)
Milepoint
Reach # (mg/1)
(00/1)
00/1)
(mgd)
Segment 1
5.14
4.80
3
Reach 1
7.50
9.00
5.00
1.37000
Reach 2
0.00
0.00
0.00
0.00000
Reach 3
0.00
0.00
0.00
0.00000
Reach 4
0.00
0.00
0.00
0.00000

SUMMER
B005/NH3N = 5/2
7Q10 = 10.0 CFS
__________ MODEL RESULTS _-____----
Discharger : LOUISBURG WWTP
Receiving Stream : TAR RIVER
----------------------------------------------------------------------
The End O.O. is 5.48 mg/l.
The End CB00 is 0.87 mg/l.
The End NB00 is 0.27 mg/l.
----------------------------------------------------------------------
WLA
WLA
WLA
00 Min CB00
NBOD
00
Waste Flow
(mg/1) Milepoint Reach # (mg/1)
(mg/1)
(mg/1)
(mgd)
Segment
1
5.22 4.80 3
Reach
1
7.50
9.00
5.00
1.37000
Reach
2
0.00
0.00
0.00
0.00000
Reach
3
0.00
0.00
O.©O
0.00000
Reach
4
0.00
0.00
0.00
0.00000

SUMMEN
.
CBOD5/NH3N =
8/3
7Q10
= 13.0
CFS
----------
MODEL RESULTS ------
---
Discharger
:
LOUISBURG
WWTP
Receiving Stream :
TAR RIVER
-----------------------------------------------------------------------
The End D.O.
is 5.18
mg/1.
The End CB00
is 1.31
mg/l.
The End NBOD
----------------------------------------------------------------------
is 0.43
mg/l.
WLA
WLA
WLA
00 Min
CBOD
NBOD
DO
Waste Flow
(mg/1)
Milepaint
Reach # (m9/1)
(mg/1)
(mg/1)
(mgd)
Segment 1
5.02
5.40
3
Reach 1
14.40
13.50
5.00
1.37000
Reach 2
0.00
0.00
0.00
0.00000
Reach 3
0.00
0.00
0.00
0.00000
Reach 4
0.00
0.00
0.00
0.00000

SUMMER
.
C6005/NH3N T 8/3
7Q10 =
13.0 CFS
Seg #
Reach #
Seg Mi
D.O.
CB00
NB00
Flaw
1
1
0.00
6.98
3.74
2.76
15.12
1
1
0.06
6.90
3.70
2.70
15.12
1
1
0.16
6.82
3.66
2.65
15.12
1
1
0.24
6.75
3.62
2.60
15.12
1
1
0.32
6.68
3.59
2.56
15.12
1
1
0.40
6.61
3.55
2.51
15.12
1
1
0.48
6.54
3.51
2.46
15.12
1
1
0.56
6.48
3.47
2.42
15.12
1
1
0.64
6.41
3.44
2.37
15.12
1
1
0.72
6.35
3.40
2.33
15.12
1
1
0.80
6.29
3.37
2.29
15.12
1
2
0.80
6.31
3.35
2.27
15.32
1
2
0.90
6.23
3.30
2.22
15.32
1
2
1.00
6.17
3.26
2.17
15.32
1
2
1.10
6.10
3.22
2.12
15.32
1
2
1.20
6.04
3.18
2.07
15.32
1
2
1.30
5.97
3.13
2.02
15.32
1
2
1.40
5.92
3.09
1.97
15.32
1
2
1.50
5.86
3.05
1.93
15.32
1
2
1.60
5.81
3.01
1.88
15.32
1
2
1.70
5.75
2.97
1.84
15.32
1
2
1.80
5.70
2.93
1.80
15.32
1
2
1.90
5.66
2.90
1.76
15.32
1
2
2.00
5.61
2.86
1.71
15.32
1
2
2.10
5.57
2.82
1.68
15.32
1
2
2.20
5.53
2.78
1.64
15.32
1
2
2.30
5.49
2.75
1.60
15.32
1
2
2.40
5.45
2.71
1.56
15.32
1
2
2.50
5.41
2.68
1.53
15.32
1
2
2.60
5.38
2.64
1.49
15.32
1
2
2.70
5.35
2.61
1.46
15.32
1
3
2.70
5.39
2.59
1.45
15.62
1
3
3.00
5.30
2.49
1.35
15.62
1
3
3.30
5.23
2.40
1.26
15.62
1
3
3.60
5.17
2.31
1.17
15.62
1
3
3.90
5.12
2.22
1.10
15.62
1
3
4.20
5.08
2.13
1.02
15.62
1
3
4.50
5.05
2.05
0.95
15.62
1
3
4.80
5.03
1.97
0.89
15.62
1
3
S.10
5.02
1.89
0.83
15.62
1
3
5.40
5.02
1.82
0.77
15.62
1
3
5.70
5.02
175
D.72
15.62
1
3
6.00
5.03
1..68
0.67
15.62
1
3
6.30
5.04
1.62
0.63
15.62
1
3
8.60
S.06
1.56
0.59
15.62
1
4
6.60
5.06
1.56
0.59
15.62
1
4
6.70
5.06
1.53
0.57
15.62
1
4
6.80
5.07
1.51
0.56
15.62
1
4
6.90
5.08
1.49
0..55 ti
15.62
1
4
7.00
5.09
1.48
0.53
15.62
1
4
7.10
5.10
1.46
0.52
15.62
1
4
7.20
5.11
1.44
0.51
15.62
1
4
7.30
5.12
1.42
0.50
15.62
1
4
7.40
5.13
1.40
0.49
15.62
1
4
7.50
5.14
1.38
0.47
15.62
1
4
7.60
5.15
1.36
0.46
15.62
1
4
7.70
5.16
1.34
0.45
15.62
1
4
7.80
5.17
1.33
0.44
15.62
1
4
7.90
5.18
1.31
0.43
15.62
Seg #
Reach #
Seg Mi
0.0. E
CBOD
NBOD
Flow f

* MODEL SUMMARY DATA
Discharger• : L_OUISBURG WWTP Subbasin 030301
Receiving Stream : TAR RIVER Stream Class: WS-III NS
Summer• 7Q10 : 13.0 Winter, 7010 : 48.0
Design Temper•atur•e: 26.0
ILENGTH1
SLOPEI
VELOCITY
I OEPTHI
Kd
I Kd
I Ka I
Ka I
KH
I KH
I KHR I
KHR
I S00
I Sao I
----------------------------------
I mile I
ft/mil,
fps
:--------------------------------------------------------------------------------
I ft Idesignl 1201
Idesignl
@201 Idesignl @201
Idesignl
@201
Idesignl @20° 1
Segment 1
I I
1 0.801
I
1.481
0.125
I I
1 2,84 1
0,27
I
1 0.20
I I
1 0.27 1
I
0.241
I
0.48
1 0.30
I I
1 0.48 1
0.00
I
1 0.00
1 0,00 1
Reach 1
--------------
I I
-----•-------_--------------------------------------------------------------------------------------
I
I I
I
I I
I
I
I 1
I
Segment 1
I I
1 1,901
I
1.481
0.125
I I
1 2.86 1
0,27
I
1 0.20
I I
1 0.21 1
I
0.241
I
0.48
1 0.30
I I
1 0.40 1
0,00
1
1 0,00
I
1 0,00 1
Reach 2
1 1
1
1 1
1
1 1
1
1
1 1
1
Segment 1
I I
1 3.901
I
1,481
0,125
I I
1 2,88 1
0.27
I
1 0.20
I I
1 0.21 1
I
0.241
I
0,48
1 0.30
I I
1 0.48 1
0.00
I
1 0.00
I
1 0,00 1
Reach 3
---------------------------------------
1 1
1
1 I
----------------------------------------------------------------------------
1
1 1
1
1
1 1
1
Segment 1
I I
1 1.301
I
1,481
0.125
I I
1 2.89 1
0.27
I
1 0.20
I I
1 0,21 1
I
0.241
I
0.48
1 0,30
I I
1 0.40 1
0.00
I
1 0.00
1 0.00 1
Reach 4
1 1
1
1 1
1
1 1
1
1
1 1
1
I Flow 1
CBOD I
NBOD 1
D.O.
1 cfs I
mg/l I
mg/l I
mg/l
Segment 1
Reach 1
Waste
1 2.123 114.400
1
13.500 I
5.000
Weadwater•sl 13.000 1
2.000 1
1.000 1
7.300
Tributary
1 0.000 1
2.000 1
1.000 1
7.300
* Runoff
1 0.000 1
2.000 1
1.000 I
7.300
Segment 1
Reach 2
Waste
I 0.000 1
0.000 I
0.000 1
0.000
Tr,ibutar•y
1 0.200 1
2.000 1
1.000 1
7.300
* Runoff
I 0.000 1
2.000 I
1.000 I
7.300
Segment 1
Reach 3
Waste
I 0.000 1
0.000 1
0.000 1
0.000
Tr•ibutar,y
1 0.300 1
2.000 1
1.000 1
7.300
* Runoff
1 0.000 1
2.000 I
1.000 1
7.300
Segment 1
Reach 4
Waste
1 0.000 1
0.000 I
0.000 1
0.000
Tributary
1 0.000 1
2.000 1
1.000 1
7.300
* Runoff
l 0.000 I
2.000 1
1.000 I
7.300
* Runoff flow is in cfs/mile