NC0084425_Permit (Issuance)_20140613

NPDES DOCUMENT SCANNING COVER SHEET
NPDES Permit:
NC0084425
Davidson Water WTP
Document Type:
Permit Issuance
Wasteload Allocation
Authorization to Construct (AtC)
Permit Modification
Complete File - Historical
Engineering Alternatives (EAA)
Staff Report
Instream Assessment (67b)
Speculative Limits
Environmental Assessment (EA)
Permit
History
Document Date:
June 13, 2014
This document is printed on reuse paper. - ignore any
content on the re Terse side

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FbENR
North Carolina Department of Environment and Natural Resources
Division of Water Resources
Pat McCrory
Governor
Ron Sink, CEO / General Manager
Davidson Water, Inc.
P.O. Box 969
Welcome, North Carolina 27374
Dear Mr. Sink:
John E. Skvarla, III
Secretary
June 13, 2014
Subject: Issuance of NPDES Permit NC0084425
Davidson Water Plant
388 Koonts Road, Lexington 27295
Davidson County
The Division of Water Resources (DWR of the Division) has approved your application to renew the subject
permit. Accordingly, we hereby forward the attached NPDES discharge permit. We issue this permit pursuant
to the requirements of North Carolina General Statute 143-215.1 and the Memorandum of Agreement between
North Carolina and the U.S. Environmental Protection Agency (EPA) dated October 15, 2007 (or as
subsequently amended).
Changes for Renewal. The Division updated your permit in accord with permitting strategies (amended
in 2009) for potable water treatment plants (WTPs) applying conventional WTP treatment technology.
We have also updated your facility description and site map, and have added test -method parameter
codes for your convenience [see Section A. (1.)].
Whole Effluent Toxicity (WET) Test Failures - Special Condition A. (4). The Division notes that this
facility has failed 14 of 20 quarterly WET tests. This failure history suggests that this facility's
wastewater may be harmful to the aquatic environment, and the cause(s) of failure must be identified.
The Division therefore may reopen this permit, or request by letter that the Permittee take further
action. This action may include additional metals testing, a Toxicity Identification Evaluation /
Toxicity Reduction Evaluation (TIE/TRE), and additional evaluation of discharge alternatives and/or
waste treatment alternatives [see Special Condition A. (4)].
A system -discharge evaluation should likely begin by establishing the receiving -stream flow and this
facility's instream waste concentration (IWC), as the IWC relates directly to effluent dilution for WET
testing. Modeling of the effluent dilution at this facility's point of discharge may allow for toxicity
testing at a lower effluent concentration (the dilution concentration) which could result in passing the
WET test. For further discussion of test methods and options, please contact Carol Hollencamp,
Aquatic Toxicology Branch (ATB) at 919-743-8401.
Implementing_Electronic Discharge Monitoring Reports (eDMRs). Please be advised that the Division
will implement an electronic Discharge Monitoring Report (eDMR) program, in accord with pending
1617 Mail Service Center, Raleigh, North Carolina 27699-1617
Location: 512 N. Salisbury St Raleigh, North Carolina 27604
Phone: [phone] FAX: [phone] Customer Service: 1-877-623-6748
Internet www.ncwaterquality.org
An Equal Opportunity 1 Affirmative Action Employer

requirements by the EPA. We have included the details required to implement the eDMR program in
this permit [see permit Special Condition A. (2.)].
Proposed federal regulations require electronic submittal of all DMRs and specify that, if North
Carolina does not establish a program to receive such submittals, Permittees must then submit eDMRs
directly to EPA. For more information on eDMRs, registering for eDMR submittal, and obtaining an
eDMR user account, please visit DWR's webpage:
[http://portal.ncdenr.org/web/wq/admin/bog/ipuiedmr].
For information on EPA's proposed NPDES Electronic Reporting: Rule, please visit EPA's website:
. - [http://www2.epa.gov/compliance/proposed-npdes-electronic-reporting-rule]
If any parts, measurement frequencies or sampling requirements contained in this permit are
unacceptable to you, you have the right to an adjudicatory hearing upon written request within thirty
(30) days following receipt of this letter. This request must be in the form of a written petition,
conforming to Chapter 150B of the North Carolina General Statutes, and filed with the Office of
Administrative Hearings (6714 Mail Service Center, Raleigh, North Carolina 27699-6714). Unless
such demand is made, this decision shall be final and binding.
Please note that this permit is not transferable except after notice to the Division. The Division may
modify, revoke, and/or reissue this permit. This permit does not affect your legal obligation to obtain.
other permits required by the Division of Water Quality, the Division of Land Resources, the Coastal
Area Management Act, or any other Federal or Local governmental permit.
If you have any questions, please contact Joe R. Corporon, L.G. at [joe.corporon@a ncdenr.gov] or call.
his direct line [phone].
Thomas A. Reeder, Directo
Division of Water Resources
Enclosure: NPDES Permit.NC0084425 (issuance final)
hc: WSRO/SWPS Supervisor, Corey Basinger
Central Files
NPDES Program Files
ec: DWR/WSRO, Corey Basinger
ATB Susan Meadows and Carol Hollencamp
Davidson Water, Inc., Ron Sink [[e-mail]];
Davidson Water, Inc., Tom Johnson [[e-mail]
1617 Mail Service Center, Raleigh, North Carolina 27699-1617
Location: 512 N. Salisbury St Raleigh, North Carolina 27604
Phone: [phone] FAX: [phone] \ Customer Service: 1-877-623-6748
Internet www.ncwaterquality.org
An Equal 0pportunily \ Affirmative Action Employer

NPDES Permit NC0084425
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES
DIVISION OF WATER RESOURCES
PERMIT
TO DISCHARGE WASTEWATER UNDER THE
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM
(NPDES)
In compliance with the provisions of North Carolina General Statute 143-215.1, other lawful
standards and regulations promulgated and adopted by the North Carolina Environmental
Management Commission, and the Federal Water Pollution Control Act, as amended, the
Davidson Water, Inc.
is hereby authorized to discharge wastewater from a facility located at the
Davidson Water Plant
388 Koonts Road; Lexington
Davidson County
to receiving waters designated as the Yadkin River within the Yadkin -Pee Dee River Basin in
accordance with effluent limitations, monitoring requirements, and other conditions set forth in
Parts I, II, III and IV hereof.
This permit shall become effective July 1, 20141.
This permit and authorization to discharge shall expire at midnight on May 31, 2017.
Signed this day June 13, 2014.
as A. Reeder, Director
'vision of Water Resources
By Authority of the Environmental Management Commission

Permit NC0084425
SUPPLEMENT TO PERMIT COVER SHEET
All previous NPDES Permits issued to this facility, whether for operation or discharge are hereby
revoked. As of this permit issuance, any previously issued permit bearing this number is no longer
effective. Therefore, the exclusive authority to operate and discharge from this facility arises under
the permit conditions, requirements, terms, and provisions included herein.
Davidson Water, Inc.
is hereby authorized to:
1. continue operating wastewater treatment facilities to produce potable water [1.144 MOD] using
WTPconventional technology [coagulation, flocculation, sedimentation, and filtration]
generating filter -backwash wastewater [Ave. 0.375 MOD] and waste solids (sludge) utilizing;
• three (3) each raw water impoundment lakes (Yadkin River source)
• six (6) each paddle flocculation basins
• two (2) each super -pulsator clarifiers
• six (6) each sedimentation basins
• twenty (26) multi -media filters
• backwash water holding tank(s) [proposed]
• sludge thickener [119 gpolft2]
• sludge screw press [proposed]
backwash water holding lagoons
while employing the following chemicals;
> aluminum sulfate [(Al2 (SO4)3]
> ferric sulfate [Fe2 SO4]
> fluoride [F]
> zinc -orthophosphate [Zn3 (PO4)2]
> sodium hydroxide [Na0H]
> lime [CaCO3]
> sulfuric acid [H2SO4]
> chlorine dioxide [C102]
from facilities located at the Davidson Water Plant, 388 Koonts Road, Lexington, Davidson
County; and
3. discharge from said treatment works via Outfall 001, at the location specified on the
attached map, into the Yadkin River [Stream Index 12-(97.5)], a waterbody currently
classified WS-IV; CA within Subbasin 03-07-04 of the Yadkin -Pee Dee River Basin.
Page 2 of 6

Permit NC0084425
PART I
A. (1.) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
During the period beginning on the effective date of this permit and lasting until expiration, the
Permittee is authorized to discharge from Outfall 001. Such discharges shall be limited and
monitored, and reported 1 by the Permittee as specified below:
EFFLUENT CHARACTERISTICS
(PARAMETER CODES)
LIMITS
MONITORING REQUIREMENTS 1
Monthly
Average
Daily
Maximum
Measurement
Frequency
Sample
Type
Sample
Location
Flow
50050
•
` Continuous
Recording
Effluent
Total Suspended Solids (TSS)
00530
30.0 mg/L
45.0 mg/L
2/Month
. Grab
Effluent
Total Residual Chlorine (TRC)2
50060
2
17µg/L.
2/Month
Grab
Effluent
Turbidity 3
00076
2/Month
Grab
Effluent
pH [standard units]
00400
Not < 6.0 nor > 9.0
2/Month
Grab
Effluent
Total Manganese 4
01055
200 µg/L
Monthly
Grab
Effluent
Total Fluoride
00951
1,800 µg&L
Monthly
Grab
Effluent
Total Aluminum 4
01105
Quarterly
Grab
Effluent
Total Iron 4
01045
Quarterly
Grab
Effluent .
Total Copper 4
01042
Quarterly
Grab
Effluent
Total Zinc 4
01092
Quarterly
Grab
Effluent
Total Phosphorous (TP) 4
C0665
Quarterly
Grab
• Effluent
Total Nitrogen (TN) 4 •
. C0610
•
Quarterly
. Grab
Effluent
WET -Testing 5 . •
TGP3B
Quarterly
. Grab
Effluent
Footnotes:
1. No later. than: February 28, 2015 (approximately 270 days from the permit effective date), begin -submitting .
electronic discharge Monitoring Reports (eDMRs) using DWR's eDMR application system, or apply for a waiver
[See Section A. (3.)].
2. Total Residual Chlorine (TRC) - The Division shall deem compliant all effluent TRC values reported below
50µg/L. However, the Permittee shall record and submit all values detected by North Carolina -certified test •
methods (including field certified), even if these values are detected below 50µg/L.
3. Turbidity - Discharge from this facility shall not cause receiving -stream turbidity to exceed 50 NTU. If natural
background turbidity exceeds 50 NTU, this discharge shall not increase receiving stream turbidity.
4. Parameter to be sampled concurrently with WET -test sampling.
5. Whole Effluent Toxicity (WET) testing conducted as Chronic [TGP3B] using Ceriodaphnia dubia, 7-day pass/fail
@ 90% effluent concentration, during the months of February, May, August and November [see Section A. (2.)].
Conditions:
• All samples collected shall accurately represent an effluent discharge event.
• The Permittee shall discharge no floating solids or foam.
• This permit includes a Special Condition regarding WET -test compliance [see Section A. (4.)].
Page 3 of 6

Permit NC0084425
A. (2.) CHRONIC TOXICITY PASS/FAIL MONITORING (QUARTERLY)
The Permittee shall conduct quarterly chronic toxicity tests using test procedures outlined in the "North
Carolina Ceriodaphnia Chronic Effluent Bioassay Procedure," Revised December 2010, or subsequent
versions.
The effluent concentration defined as treatment two in the procedure document is 90%. The testing shall be
performed as a Ceriodaphnia dubia 7-day pass/fail test. The tests will be performed during the months of
February, May, August and November. These months signify the first month of each three-month
toxicity -testing quarter assigned to the facility. Effluent sampling for this testing must be obtained during
representative effluent discharge and shall be performed at the NPDES permitted final effluent discharge
below all treatment processes.
All toxicity testing results required as part of this permit condition will be entered on the Effluent Discharge
Monitoring Form (MR-1) for the month in which it was performed, using the parameter code TGP3B.
Additionally, DWR Form AT-1 (original) is to be sent to the following address:
Attention: North Carolina Division of Water. Resources
Environmental Sciences Section
1621 Mail Service Center
Raleigh, N.C. 27699-1621
Completed Aquatic Toxicity Test Forms shall be filed with the Environmental Sciences Section no later than
30 days after the end of the reporting period for which the report is made.
Test data shall be complete and accurate and include all supporting chemical/physical measurements
performed in association with the toxicity tests, as well as all dose/response data. Total residual chlorine of
. the effluent toxicity sample must be measured and reported if chlorine is employed for disinfection of the
waste stream.
• Should there be no discharge of flow from the facility during a month in which toxicity monitoring is
required; the Permittee will complete the information located at the top of the aquatic toxicity (AT) test form
indicating the facility name, permit number, pipe number, county, and the month/year,of the report with the
....notation of."No Flow" in the comment area of the form. The report shall be submitted to the Environmental
Sciences Section at the address cited above.
Should -the Permittee fail to monitor during a month in which toxicity monitoring is required, then.monthly
monitoringwill begin immediately. Upon submission of a valid test, this monthly test requirement will
revert to quarterly in the months specified above.
Should .any test data from this monitoring requirement or tests performed by the North Carolina Division of
Water Resources indicate potential impacts to the receiving stream, this permit may be re -opened and
modified to 'include alternate monitoring requirements or limits.
If the Permittee monitors any pollutant more frequently than required by this permit, the results of such
monitoring shall be included in the calculation & reporting of the data submitted on the DMR & all AT
Forms submitted. •
NOTE: Failure to achieve test conditions as specified in the cited document, such as minimum control
organism survival, minimum control organism reproduction, and appropriate environmental controls, shall
constitute an invalid test and will require immediate follow-up testing to be completed no later than the last
day of the month following the month of the initial monitoring.
Page 4 of 6

Permit NC0084425
A. (3.) ELECTRONIC REPORTING - DISCHARGE MONITORING REPORTS
Proposed federal regulations require electronic submittal of all discharge monitoring reports
(DMRs) and specify that, if a state does not establish a system to receive such submittals, then
Permittees must -submit DMRs electronically to the Environmental Protection Agency (EPA). The
Division anticipates that these regulations will be adopted and will begin implementing in 2013.
NOTE: This special condition supplements or supersedes the following sections within Part II of
this permit (Standard Conditions for NPDES Permits):
• Section B. (11.)
• Section D. (2.)
• Section D. (6.) •
• Section E. (5.)
Signatory Requirements
Reporting
Records Retention
Monitoring Reports
1. Reporting (Supersedes Part 11 Section D. (2.) and Section E. (5.) (a)1
Beginning no later than no later than February 28, 2015 (approximately 270 days from the effective -
date of this permit), the Permittee shall begin reporting discharge monitoring data electronically
using the NC DWR's Electronic Discharge Monitoring Report (eDMR) internet application.
Monitoring results obtained during the previous month(s) shall be summarized for each month
and submitted electronically using eDMR. The eDMR system allows permitted facilities to -
enter monitoring data and submit DMRs electronically using the internet. Until such time that
the state's eDMR application is compliant with EPA's Cross -Media Electronic Reporting
Regulation (CROMERR), Permittees will be required to submit all discharge monitoring data to
the state electronically using eDMR and will be required to complete the eDMR submission by
printing, signing, and submitting one signed original and a copy of the computer printed eDMR
to the following address:
NC DENR / DWR / Information Processing Unit
ATTENTION: Central Files I eD MR
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
If a Permittee is unable to use the eDMR system due to a demonstrated hardship or due to the
facility being physically located in an area where less than 10 percent of the households have
broadband access, then a temporary waiver -from the NPDES electronic reporting requirements
may be granted and discharge monitoring data may be submitted on paper DMR forms (MR 1,
1.1, 2, 3) or alternative forms approved by the Director. Duplicate signed copies shall be
submitted to the mailing address above.
Requests for temporary waivers from the NPDES electronic reporting requirements must be
submitted in writing to the Division for written approval at least sixty (60) days prior to the date
the facility would be required under this permit to begin using eDMR. Temporary waivers shall
be valid for twelve (12) months and shall thereupon expire. At such time, DMRs shall be
submitted electronically to the Division unless the Permittee re -applies for and is granted a new
temporary waiver by the Division.
Page 5 of 6

Permit NC0084425
Information on eDMR and application for a temporary waiver from the NPDES electronic
reporting requirements is found on the following web page:
http://portal.ncdenr.org/web/wq/admin/bog/ipu/edmr
Regardless of the submission method, the first DMR is due on the last day of the month
following the issuance of the permit or in the case of a new facility, on the last day of the month
following the commencement of discharge.
2. Signatory Requirements [Supplements Part IL Section B. (11.) (b) and supersedes Section B. (11.)
fin"
All eDMRs submitted to the permit issuing authority shall be signed by a person described in
Part II, Section B. (11.)(a) or by a duly authorized representative of that person as described in
Part II, Section B. (11.)(b). A person, and not a position, must be delegated signatory authority
for eDMR reporting purposes.
For eDMR submissions, the person signing and submitting the DMR mast obtain an eDMR user
account and login credentials to access the eDMR system. For more information on North
Carolina's eDMR system, registering for eDMR and obtaining an eDMR user account, please
visit the following web page:
http://portal.ncdenr.orWweb/wq/admin/bog/ipu/edmr
Certification. Anyperson submitting an electronic DMR using the state's•eDMR system shall.
•
make the following certification [40 CFR 122.22] . NO OTHER STATEMENTS OF
CERTIFICATION WILL BE ACCEPTED:
"I. certifii, under penalty of law, that this. document and all attachments were prepared under my
• direction or, supervision in accordance. with a system designed to assure that qualified personnel
properly gather and evaluate.the information submitted Based on my inquiry of the person or
persons who manage the system; or those persons directly responsible for gathering the
•
information, the information submitted is, to the best of my knowledge and belief true, accurate,
and complete. I am aware that there are significant penalties for submitting false information,
including the possibility of fines and imprisonment for knowing violations."
3. Records Retention (Supplements Part II, Section D. (6.)1
The Permittee shall: retainrecords of all Discharge Monitoring Reports, including eDMR submissions.
These records or copies shall be maintained for a period of at least 3 years from the date of the report.
This period may be extended by request of the Director at any time [40 CFR 122.41].
A. (4.) PERMIT RE -OPENER - WHOLE EFFLUENT TOXICITY MONITORING
Whole Effluent Toxicity (WET) monitoring results indicate that this surface -water discharge may be toxic to
the aquatic environment. The Division of Water Resources therefore may reopen this permit, or request by
letter that the Permittee take further action. This action may include additional metals testing, a Toxicity
Identification Evaluation / Toxicity Reduction Evaluation (TIE/TRE), and additional assessment of
discharge alternatives and/or waste treatment alternatives.
Page 6 of 6
•

850
11\
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1
\- :f 4 ` ✓i
-� A f
0 ice_ ,1 C. '
f--^ .\ N-__.. Outfall 001
t ` ( ) • Lat: 35° 51' 13 N
,, 1� Long: 80° 23' 25" W
l o
,.....,..,
7.nn ~ 1 v
f f
f /
Davidson Water, Inc.
Davidson Water Treatment Plant
State Grid/Quad: DI 7SW /Churchland, NC Sub -Basin: 03-07-04
Permitted Flow: not limited Stream Class: WS-IV; CA
Receiving Stream: Yadkin River Stream Segment: 12-(97.5)
Drainage Basin: Yadkin— Pee Dee Basin HUC: 03040101
NPDES Permit NC0084425
Davidson County
Facility
Location -
not to scale
North

FILE CONTENTS:
Le side:
BIMS Tracking Slip
Right side:
❑ Streamline Package Sheet
Er Draft Permit Cover Letter.
Ff Draft Permit
:2 Facility Map
[8' Fact Sheet
Permit Writer's Notes
Staff Report from Region
Old Permit
Permit Application.
cknowledgement Letter
Permittee Responses
Waste Load Allocation
Note: Italics indicate special
/MSupdate "initia
it
z�' Submitted to
Facility
NPDES PERMIT RENEWAL
DRAFT / FINAL
►,-\lic-rfA\J
Permit No. DECO s4eRQ,✓
NPDES Permit Writer:
(to region, only if streamlined)
Joe R'Corporgit, L.G " OC
(add new policy text; summarize major changes . co permit)
(order: cover, Sup to Cover Sheet, effluent page((s), special conditions, map)
(E-Map: include facility Outfalls; U and D sample locations)
(documents permit writer's issues and re -issue Logic)
(if not in Facts Sheet -- chronology, strategy, DMR Review, RPA, etc.)
(as appropriate -- not needed if streamlined)
(Text, Effluent Sheets and Special Conditions)
(New Permit or Renewal; any additional permittee correspondence)
(NPDES Unit written response to Renewal Application)
(to acknowledgement letter, if any)
(reference date; notes if recalculated for current action)
conditions not always required or applicable.
d DRAFT review" Date:
❑ Updated Publ
/ Lao (4-
for Peer Review: Date
Peer Review completed by xp
is Notice System [date] L
❑ Submitted for Public Notice on
Er -Draft Permit [Mailed
Emailed
❑ Regional Office Reviewed
((
❑ Additional Review by T
Admin cutoff / PN date AN
Date azAP -
Updated BIMS Events: [date]
. Newspaper Notice Received
to (Regional Staff) (fie Y pt5("A
pproved by
Wi.)--
/V'INAL
• Additional Review/Appral b`lDate t. John / :ff / Matt / for signature [date]isg.3_0
F� Letter Date .� C)PJ
/Additional Review [other] M'Ot riMkt TO . A l if U S 8 ?`e'NP ( of
❑ Finals transferred to Server (Permits Folder) 0.00..b( 1MS Final Updates: Events ✓ Limit j_
. Actual Notice date(s).
by Date 1i34M%
[Date]
-)'VS ini iated by Date 2 .54
P3cIA
❑
Version 1 l Feb2014

DENR / DWR / NPDES
EXPEDITED FACT SHEET - NPDES PERMIT RENEWAL
NPDES Permit NC0084425/
i
(
Joe R. Corporon, L.G., Compliance and Expedited Permitting Uni
I0Jun2014 v2
Facility Information
Facility Name
Davidson Water Plant
Applicant
Davidson Water, Inc.
Contact
Ron Sink, CEO / General ' anaQer
[[e-mail]]
Applicant Address
P.O. Box 969 Welcome 27374
Facility Address
388 Koonts Road, Lexington 27295
Permitted Flow (MGD)
Not limited
Type of Waste
Potable WTP / filter backwash (Conventional treatment Technology).
Facility Class
County
Davidson
Facility Status
Renewal
Regional Office
WSRO
Stream Characteristics
Receiving Stream / Basin
UT to Yadkin River
Stream Classification
WS-IV; CA
Stream Segment
12-(97.5)
Drainage Basin
Yadkin -Pee Dee
Summer 7Q10 (cfs)
—
Subbasin
03-07-04
Winter 7Q10 (cfs)
—
Use Support
Yes
30Q2 (cfs)
—
303(d) Listed
No
Average Flow (cfs)
--
State Grid
D17SE
IWC (ova)
Not established.
Assumed 100% (?)
USGS Topo Quad
Lexington, NC
Facility Summary: This WTP employs conventional treatment technology to produce potable water at a design rate
of 35.0 MGD while generating wastewater (filter -backwash) at an average rate of 0.375 MGD [n = 1156] over the
last permit cycle. However, discharge rates vary greatly over a five-year period (max.1.144 MGD; min. 0.001
MGD). The Permittee corrected the draft -permit number of filters [20 to 26], and added to document their use of
ferric sulfate [Fe2 SO4]; see Supp. to Permit Cover Sheet.
Summary of Renewal Changes:
1. Permittee installed "continuous recording" first reported in January 2010 - no change recommended.
2. Within 270-days the Permittee must to begin electronic submittal of monthly DMRs (eDMRs).
3. Updated facility description [Supplement to Cover Sheet] ; updated Vicinity Map, Lat. / Long;
4. Added parameter codes to effluent table, Section A. (1.);
5. WET testing is required [conventional treatment] - no change recommended. Quarterly WET test history
shows 14 of 20 test failed (TGP3B @ 90%). Upon written notice from the Aquatic Toxicology Branch
(ATB), the Permittee is required to evaluate and correct the cause(s) of WET -test failure. ATB has
agreed to follow up permit issuance with NOV letters to all Conventional WTP failing toxicity [see
Special Condition A. (4.)].
Turbidity Data - Jan2010-Mar2014: (n = 106): Max = 2760 ntu; Min = 1 ntu; Ave. = 35 ntu
Reasonable Potential Analysis (RPA). Data show reasonable potential for Mn, Fe, Cu, F, and Zn (see attached);
therefore monitoring is required [see Section A. (1.)]. The non -action level parameters Mn and F require permit
limits equal to their standard considering zero -flow discharge conditions (no IWC/no dilution established for this
facility's discharge).
Fact Sheet
Renewal 2014 -- NI'I)I:S I'ermit NC0084425
Page 1 of 1

2014 Freshwater RPA - 95% Probability/95% Confidence
MAXIMUM DATA POINTS = 58
REQUIRED DATA ENTRY
Table 1. Project Information
❑ CHECK IF HQW OR ORW WQS
Facility Name
WWTP/WTP Class
NPDES Permit
Outfall
Flow, Qw (MGD)
Receiving Stream
Stream Class
7Q10s (cfs)
7Q10w (cfs)
30Q2 (cfs)
QA (cfs)
1Q10s (cfs)
Data Source(s)
Davidson Water Plant , Inc.
NC0084425
001
1.144
UT to the Yadkin River
WS-IV: CA
0.00
0.00
0.00
0.00
0.00
❑ CHECK TO APPLY MODEL
BIMS DMRS Jan2010 - Mar2014
Follow directions for data entry. In some cases a
comment menu list the available choices or a
dropdown menu will provide a list you may select
from. Error message occur if data entry does not
meet input criteria.
FLOW: Qw = maximum reported during permit cycle
Table 2. Parameters of Concern
Par01
Par02
Par03
Par04
Par05
Par06
Par07
Par08
Par09
Par10
Par11
Par12
Par13
Par14
Par15
Par16
Par17
Par18
Par19
Par20
Par21
Par22
Name
Type Chronic
Modifier Acute
PQL
Units
h•
w
w
a
•
❑
■
■
•
■
Copper (AL)
NC
7
FW
7.3
ug/L
■
❑
Fluoride
NC
1,800
FW
ug/L
❑
■
■
I1
•
Znc (AL)
NC
50
FW
67
ug/L
•
Manganese
NC
200
WS
pg/L
❑
Aluminum
NC
6500
FW
8000
pg/L
•
Iron
NC
1000
WS
pg/L
•
1
84425 RPA - 9595 FRESHWATER 2014.xlsx, input
4/23/2014

Davidson Water Plant , Inc. 2014 Freshwater RPA - 95% Probability/95% Confidence
NC0084425
Qw (MGD) = 1.14
1QIOS(cfs)= 0.00
7Q10S (cfs) = 0.00
7Q10W(cfs)= 0.00
30Q2 (cfs) = 0.00
Avg. Stream Flow, QA (cfs) = 0.00
Receiving Stream: UT to the Yadkin River
MAXIMUM DATA POINTS = 58
WWTP/WTP Class:
IWC @ IQ10S = 100.00%
IWC @ 7Q10S = 100.00%
IWC @ 7Q1OW = 100.00%
IWC @ 30Q2 = 100.00%
IWC @ QA = 100.00%
Stream Class WS-IV; CA
Outfall 001
Qw = 1.144 MGD -
Qw = maximum reported during permit cycle
PARAMETER
TYPE
(1)
STANDARDS & CRITERIA (2)
PQL
UNITS
REASONABLE POTENTIAL RESULTS
RECOMMENDED ACTION
NC WQS /
Chronic
Applied
Standard
/ FAV /
Acute
Il
Max Pred
/J Dot. Cw Allowable Cw
Copper (AL)
NC
7
FW
7.3
ue/I.
16
7
66
Acute: • 7.3
Chronic: 7.0
3 value(s) > Allowable Cw
RP for AL(Cu,Zn,Ag,Fe,CI) - apply Quarterly
Monitoring in conjunction with TOX Test
RP for AL(Cu,Zn,Ag,Fe,CI) - apply Quarterly
Monitoring in conjunction with TOX Test
Fluoride
NC
IS00
FW
ue/l.
16
13
1,92S
Acute: NO WQS
_ _ _____ _ __
Chronic: 1,800
No value > Allowable Cw
_ _ _ _ _ _
RP for non -AL - apply Monthly Monitoring with Limit
Zinc (AL)
NC
50
FW
67
ug/L
17
17
470
Acute: 67
Chronic: 50
10 value(s) > Allowable Cw
RP for AL(Cu,Zn,Ag,Fe,CI) - apply Quarterly
Monitoring in conjunction with TOX Test
RP for AL(Cu,Zn,Ag,Fe,CI) apply Quarterly
Monitoring in conjunction with TOX Test
Manganese
NC
200
WS
µg/L.
16
I
2,745
Acute: NO WQS
_ _____ ____
Chronic: 200
9 value(s) > Allowable Cw
_ _ _ _ _ _ _ _
RP for non -AL - apply Monthly Monitoring with Limit
Aluminum
NC
6500
FW
8000
µa/l.
1
1
N/A
Acute: 8000
_ _ ______ _ __
Chronic: 6500
no data
_ _ _
no data
Iron
NC
1000
WS
ue I.
! 7
I?
13.447
Acute: NO WQS
_ _____ _ __
Chronic: 1000
11 value(s) > Allowable C‘v
_ _
RP for AL(Cu,Zn,Ag,Fe,CI) - apply Quarterly
Monitoring in conjunction with TOX Test
Page 1 of 1
84425 RPA - 9595 FRESHWATER 2014.xlsx, rpa
4/23/2014

REASONABLE POTENTIAL ANALYSIS
9
Copper (AL)
Date Data BDL=1/2DL Results
1 2010 < 5 2.5 Std Dev.
2 2010 < 5 2.5 Mean
3 2010 6 6 C.V.
4 2010 < 5 2.5 n
5 2011 < 5 2.5
6 2011 5 5 Mult Factor =
7 2011 16 16 Max. Value
8 2011 < 5 2.5 Max. Pred Cw
9 2012 < 5 2.5
10 2012 8 8
11 2012 33 33
12 2012 < 5 2.5
13 2013 < 5 2.5
14 2013 < 5 2.5
15 2013 < 5 2.5
16 2014 6 6
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
Use "PASTE SPECIAL
Values" then "COPY"
. Maximum data
points = 58
11
Fluoride
Date Data BDL=I/2DL Results
8.0 1 2010 148 148 Std Dev.
6.2 2 2010 1020 1020 Mean
1.3 3 2010 580 580 C.V.
16 4 2010 842 842 n
5 2011 < 100 50
1.99 6 2011 198 198 Mult Factor =
33.0 ug1L 7 2011 155 155 Max. Value
65.7 ug/L 8 2011 134 134 Max. Pred Cw
9 2012 165 165
10 2012 143 143
11 2012 196 196
12 2012 144 144
13 2013 < 100 50
14 2013 107 107
15 2013 101 101
16 2014 < 100 50
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
Use"PASTE SPECIAL
Values" then "COPY"
. Maximum data
points = 58
292.4
255.2
1.1
16
1.89
1020 ug/L
1928 ug/L
84425 RPA - 9595 FRESHWATER 2014.xlsx, data
- 2 - 4/23/2014

REASONABLE POTENTIAL ANALYSIS
18
Zinc (AL)
Date Data BDL=1/2DL Results
1 2010 78 78 Std Dev.
2 2010 148 148 Mean
3 2010 39 39 C.V.
4 2010 285 285 n
5 2011 77 77
6 2011 106 106 Mult Factor =
7 2011 9 9 Max. Value
8 2011 54 54 Max. Pred Cw
9 2012 29 29
10 2012 88 88
11 2012 43 43
12 2012 18 18
13 2012 54 54
14 2013 105 105
15 2013 52 52
16 2013 24 24
17 2014 40 40
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
Use "PASTE SPECIAL
Values' then "COPY"
. Maximum data
points = 58
19
Manganese
Date Data BDL=1/2DL Results
65.5 1 2010 259 259 Std Dev.
73.5 2 2010 1210 1210 Mean
0.9 3 2010 32 32 C.V.
17 4 2010 113 113 n
5 2011 510 510
1.65 6 2011 457 457 MuIt Factor =
285.0 ug/L 7 2011 128 128 Max. Value
470.3 ug/L 8 2011 216 216 Max. Pred Cw
9 2012 334 334
10 2012 98 98
11 2012 179 179
12 2012 995 995
13 2013 88 88
14 2013 1500 1500
15 2013 400 400
16 2014 78 78
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
Use"PASTE SPECIAL
Values" then "COPY"
. Maximum data
points = 58
442
412
1
16
1.83
1500 pg/L
2745 pg/L
-3-
84425 RPA - 9595 FRESHWATER 2014.xlsx, data
4/23/2014

REASONABLE POTENTIAL ANALYSIS
20
Aluminum
Date Data BDL=1/2DL Results
1 Std Dev.
2 Mean
3 C.V.
4 n
5
6 Mult Factor =
7 Max. Value
8 Max. Pred Cw
9
10
11
12
13
14
15
16 No data
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
Use "PASTE SPECIAL.
Values" then "COPY"
. Maximum data
points = 58
21
Iron
NO DATA
NO DATA
NO DATA
0
N/A
N/A pg/L
N/A pg/L
Use"PASTE Sr
Values" then "1
. Maximum
points = 5
Date Data BDL=1/2DL Results
1 2010 2620 2620 Std Dev. 1960.6233
2 2010 574 574 Mean 2040.0000
3 2010 1080 1080 C.V. 0.9611
4 2010 2010 2010 n 17
5 2011 3720 3720
6 2011 844 844 Mult Factor = 1.70
7 2011 132 132 Max. Value 7910
8 2011 1520 1520 Max. Pred Cw 13447
9 2012 1100 1100
10 2012 3070 3070
11 2012 1310 1310
12 2012 907 907
13 2013 4490 4490
14 2013 2590 2590
15 2013 7910 7910
16 2014 544 544
17 259 259
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
84425 RPA - 9595 FRESHWATER 2014.xlsx, data
- 4 - 4/23/2014

Corporon, Joe
e(NVvL fY c<>14144Z65)(
From: Tom Johnson <[e-mail]>
Sent: Tuesday, May 20, 2014 10:27 AM i.—
To: Corporon, Joe
Cc: Ron Sink; Gregg Stabler; Mary Pangan; Craig Koonts
Subject: draft NPDES Permit changes
Good Morning Joe,
Per our conversation earlier this morning, we need to make the changes listed below to the draft permit. Thanks for
your help.
On Page 2, Section 1, under "Facilities Utilized" please change the number of multi -media filters to 26. Also add
"Backwash Water Holding Tank- (Proposed)"
On Page 2, Section 1, under "Chemicals Utilized" please add Ferric Sulfate [Fe2SO4].
Tom Johnson
Plant Superintendent
I11'1F'i.tt 3\.. •
mailto:tlohnson(a�davidsonwater.com
[phone] mobil
[phone] Direct
[phone] fax
www.davidsonwater.com
1

42008346
J000474190
AFFIDAVIT OF PUBLICATION
STATE OF NORTH CAROLINA LEXINGTON, NC April 24, 2014
DAVIDSON COUNTY
I, Lynn Bowers OF THE DISPATCH, A NEWSPAPER PUBLISHED IN THE CITY OF LEXINGTON, COUNTY AND STATE
AFORESAID, BEING DULY SWORN, SAYS THE FOREGOING LEGAL OF WHICH THE ATTACHED IS A TRUE COPY,
WAS PUBLISHED IN SAID NEWSPAPER ONCE, BEGINNING THE 24th DAY OF April, 2014.
PUBLICATION FEE: $ 85.19
uurvnAw-t
(SEAL)
S O' N TO AND SUBSCRIBE I BEFORE ME, THIS
MY COMMISSION EXPIRES — j D2o/6,.
Ad Copy:
Public Notice
North Carolina
Environmental Management
Commission/NPDES Unit
1617 Mail Service Center
Raleigh, NC 27699-1617
Notice of Intent to Issue a
NPDES Wastewater Permit
The North Carolina
Environmental Management
Commission proposes to issue
a NPDES wastewater
discharge permit to the
person(s) listed below. Written
comments regarding the
proposed permit will be
accepted until 30 days after the
publish date of this notice. The
Director of the NC Division of
Water Resources (DWR) may
hold a public hearing should
there be a significant degree of
public interest. Please mail
comments and/or information
requests to DWR at the above
address. Interested persons
may visit the DWR at 512 N.
Salisbury Street, Raleigh, NC
to review information on file.
Additional information on
NPDES permits and this notice
may be found on our website:
http.//portal.ncdenr.orq/web/wq/
swp/ps/npdes/calendar, or by
calling [phone].
Davidson Water, Inc. requested
to renew permit NC0084425 for
its potable WTP, Lexington,
Davidson County, discharging
treated filter backwash to a UT
to the Yadkin River, Yadkin -Pee
Dee River Basin.
April 24, 2014
kv"
c6
DAY OF
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••` 5
▪ N°\b" Co Q\tes
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Corporon, Joe
Oso?)&00-5
0,\O - OvviNI
From: Carter, Jenifer
Sent: Thursday, April 24, 2014 9:54 AM
To: Corporon, Joe
Subject: FW: Review of NPDES DRAFT Permit NC0084425 - Davidson Water, Inc, Lexington
Attachments: 84425 Davidson Co Conventional - Cover Letter DRAFT Apr2014.pdf; 84425 Davidson
Conventional WTP BOX Apr2014 DRAFT.pdf; 84425 Davidson WTP Map Apr2014.pdf;
84425 Davidson Conventional WTP Fact Sheet Apr2014 DRAFT.pdf
Joe, sorry if you get this twice... my first attempt to respond bounced back to me.
I don't see any problems with the DRAFT permit for Davidson WTP as written. Let me know if you have any question.
Jenifer Carte
Before printing this email, please consider your budget and the environment.
If you must print. please print only what you need and save ink with the free Eco-Font.
NC DENR Winston-Salem Regional Office
Division of Water Resources
585 Waughtown Street
Winston-Salem, NC 27107
Voice: [phone]
FAX: [phone]
E-mail correspondence to and from this address may be subject to the
North Carolina Public Records Law and may be disclosed to third parties.
From: Basinger, Corey
Sent: Wednesday, April 23, 2014 2:23 PM
To: Carter, Jenifer
Subject: FW: Review of NPDES DRAFT Permit NC0084425 - Davidson Water, Inc, Lexington
Please review and respond back to Joe as appropriate.
Thanks.
CB
W. Corey Basinger
Regional Supervisor
Water Quality Regional Operations
Winston-Salem Regional Office
Division of Water Resources
Email: [e-mail]
Phone: [phone]
Fax [phone]
t

' E-mail correspondence to and from this address may be subject to the North Carolina Public Records Law and may be disclosed to
third parties.
From: Corporon, Joe
Sent: Wednesday, April 23, 2014 1:45 PM
To: rsink(davidsonwater.com
Cc: Basinger, Corey
Subject: Review of NPDES DRAFT Permit NC0084425 - Davidson Water, Inc, Lexington
For your review and comment, as needed. Hardcopy to follow by mail.
We have submitted this for Public Notice today — comment period "'30 days.
Respectfully,
Joe R. Corporon, L.G. ROC
Compliance and Expedited Permitting
WR
DAhian c! tutu Rtsc ice+ Division of Water Resources
NCDENR/ NPDES Program / Water Quality Permitting Section
919-807-6394; FAX [phone]
E-mail correspondence to and from this address may be subject to the North Carolina Public Records Law and may be disclosed to
third parties.
2

Mailing Address
Davidson Water Inc.
P.O. Box 969
Welcome, NC 27374
Lexington [phone]
Winston-Salem [phone]
Thomasville [phone]
November 21, 2013
Wren Thedford
NC DENR/DWR/NPDES Unit
1617 Mail Service Center
Raleigh, NC 27699-1617
Re: NPDES Permit Application
Permit #NC0084425
Dear Mr. Thedford:
Shipping Address
Davidson Water Inc.
7040 Old Highway 52
Lexington, NC 27295
Water Plant [phone]
Office Fax [phone]
www.davidsonwater.com
email [e-mail]
Davidson Water, Inc, is requesting renewal of the NPDES permit NC0084425. There have been several
changes at the facility since issuance of the last permit. Your office approved in December 2010 a
modification to our permit moving the outfall location by approximately 600 feet. A new sludge
thickener has been added to our process. Backwash water from our pulsators, sedbasins and filters will
now go to the sludge thickener and then decanted to our lagoons. Water will then be decanted from the
lagoons to the new outfall location approved in our modification December 2010.
Please find enclosed our application packet.
Sincerely,
Ron Sink
CEO/General Manger
RS/mp

NPDES PERMIT APPLICATION - SHORT FORM C - WTP
For discharges associated with water treatment plants
Mail the complete application to:
N. C. Department of Environment and Natural Resources
Division of Water Quality / NPDES Unit
1617 Mail Service Center, Raleigh, NC 27699-1617
NPDES Permit Number
,NC0084425
If you are completing this form in computer use the TAB key or the up - down arrows to move from one
field to the next. To check the boxes, click your mouse on top of the box. Otherwise, please print or type.
1. Contact Information:
Owner Name
Facility Name
Mailing Address
City
State / Zip Code
Telephone Number
Fax Number
e-mail Address
Davidson Water, Inc.
Davidson Water, Inc. Water Plant
PO Box 969 n EC
Welcome
NC 27374
[phone]
[phone]
OWR
DEL 0 2 2013
DENR-WATER QUALITYCH
[e-mail]
2. Location of facility producing discharge:
Check here if same as above 0
Street Address or State Road
City
State / Zip Code
County
3. Operator Information:
Name of the firm, consultant or other entity that operates the facility. (Note that this is not referring to the
Operator in Responsible Charge or ORC)
Name Davidson Water, Inc.
Mailing Address PO Box 969
City Welcome
State / Zip Code NC 27374
Telephone Number [phone]
Fax Number
388 Koonts Road
Lexington
NC 27295
Davidson
4. Ownership Status:
Federal 0
•
[phone]
State 0
Private X Public ❑
Page 1 of 3 Version 5/2012

NPDES PERMIT APPLICATION - SHORT FORM C - WTP
For discharges associated with water treatment plants
5. Type of treatment plant:
X Conventional (Includes coagulation, flocculation, and sedimentation, usually followed by
filtration and disinfection)
❑ Ion Exchange (Sodium Cycle Cationic ion exchange)
❑ Green Sand Filter (No sodium recharge)
❑ Membrane Technology (RO, nanofiltration)
Check here if the treatment process also uses a water softener
CI
6. Description of source water(s) (i.e. groundwater, surface water)
Yadkin river
7. Describe the treatment process(es) for the raw water:
Attached
8. Describe the wastewater and the treatment process(es) for wastewater generated by the
facility:
Attached
9. Number of separate discharge points: 1
Outfall Identification number(s) 001
10. Frequency of discharge:
Continuous X Intermittent 0
If intermittent:
Days per week discharge occurs: Duration:
11. Plant design potable flowrate 35 MGD
Backwash or reject flow .5 MGD
12. Name of receiving stream(s) (Provide a map showing the exact location of each outfall, including
latitude and longitude):
Yadkin River Northing 768442.661 Easting 1589564.501
13. Please list all water treatment additives, including cleaning chemicals or disinfection
treatments, that have the potential to be discharged.
Alum / aluminum sulfate
Yes X No
Page 2 of 3 Version 5/2012

NPDES PERMIT APPLICATION - SHORT FORM C - WTP
For discharges associated with water treatment plants
Iron sulfate / ferrous sulfate Yes X No
Fluoride Yes X No
Ammonia nitrogen / Chloramines Yes No X
Zinc -orthophosphate or sweetwater CP1236 Yes X No G-yl
List any other additives below: C J
Caustic, Lime, Chlorine Dioxide, Sulfuric Acid, Copper Sulfate, Polymer + (t*c.
14. Is this facility located on Indian country? (check one)
Yes ❑ No X
15. Additional Information:
Provide a schematic of flow through the facility, include flow volumes at all points in
the water treatment process. The plan should show the point[s] of addition for
chemicals and all discharges routed to an outfall [including stormwater].
Solids Handling Plan
16. NEW Applicants
Information needed in addition to items 1-15:
New applicants must contact a permit coordinator with the NCDENR Customer
Service Center.
Was the Customer Service Center contacted? ❑ Yes ❑ No
Analyses of source water collected
Engineering Alternative Analysis
Discharges from Ion Exchange and Reverse Osmosis plants shall be evaluated using a
water quality model.
17. Applicant Certification
I certify that I am familiar with the information contained in the application and that to the
best of my knowledge and belief such information is true, complete, and accurate.
Ron Sink CEO/General Manager
Printed name of Person Siygning Title
?AY--
4-4
�/- L (o - 13
Signature of Applicant Date
North Carolina General Statute 143-215.6 (b)(2) provides that: Any person who knowingly makes any false statement representation, or certification in any application,
record, report, plan, or other document files or required to be maintained under Article 21 or regulations of the Environmental Management Commission implementing that
Article, or who falsifies, tampers with, or knowingly renders inaccurate any recording or monitoring device or method required to be operated or maintained under Article 21
or regulations of the Environmental Management Commission implementing that Article, shall be guilty of a misdemeanor punishable by a fine not to exceed $25,000, or by
imprisonment not to exceed six months, or by both. (18 U.S.C. Section 1001 provides a punishment by a fine of not more than $25,000 or imprisonment not more than 5
years, or both, for a similar offense.)
Page 3 of 3 Version 5/2012

7. Describe the treatment process(es) for raw water
Water is pumped from the Yadkin River into our three storage reservoirs going to our upper lake first
and then released to the far end of the southern reservoir through a 42" water line and then it is
released into our middle reservoir giving us the longest settling time possible. If needed for algae
control we add aluminum sulfate as it goes into the reservoirs. The water is pumped from our off
stream storage reservoirs to the plant where we add chlorine dioxide, sulfuric acid if needed for PH
control, and ferric sulfate for our coagulation process. Chlorine is added for disinfection and
iron/manganese control. After coagulation and sedimentation the water is filtered through our 26
mixed media filters. After filtration we add additional chlorine for disinfection , fluoride for prevention
of dental cavities, caustic or lime for PH stabilization and zinc orthophosphate for corrosion control.
Water goes into our 5 mg clearwell through a baffling system and then distributed to our other clearwell
storage and pumped into our distribution system.
8. Describe the wastewater and treatment process(es) for wastewater generated by the facility.
Wastewater from the pulsators and sedbasins go into a sludge thickener and wastewater is decanted
out of the thickener into the existing lagoons. Backwash water from the filters is going into the lagoons
at present but will shortly be going into 500,000 gallon clearwell taken out of service and modified to
handle filter backwash and become part of the treatment process. Water will be decanted out of
500,000 gallon containment into lagoons and sludge will be pumped out of containment into the sludge
thickener. The decant water from lagoons is allowed to return to the Yadkin River after it has been
dechlorinated using calcium thiosulfate. Flow to the Yadkin is measured and tested.
15. Solid Handling Plan
Solids generated in the 500,000 gallon containment from filter backwash will be pumped into sludge
thickener. Solids in sludge thickener is transferred to our lagoons and then are land applied by an
approved outside source. EMA Reseources, Inc. has handled land application for the past several years.
Davidson Water, Inc. permit #WQ0031712.
We have recently sent in plans for a screw press to DENR and have received all approvals. We hope to
have a screw press in operation within six months giving us the ability to take solids to the Davidson
County Landfill or any approved landfill as long as solids are 15% or greater. This will give us options in
our waste handling.

DAVIDSON WATER, INCORPORATED
WATER TREATMENT PLANT UPGRADE TO 30 MGD
DESIGN CALCULATIONS
NOVEMBER 2013
1. YADKIN RIVER
NORMAL WATER ELEVATION
HISTORICAL LOW WATER ELEVATION
100 YR FLOOD ELEVATION
639' MSL
637.24' MSL
672' MSL
2. RAW WATER INTAKE
TOP OF SCREENS 633.7 MSL
ULTIMATE INTAKE CAPACITY 60 MGD
SCREEN TYPE - STAINLESS STEEL WEDGE WIRE, 4 - 60' SCREENS WITH 48' OUTLET
SCREEN INLET VELOCITY - < 0.5 FPS @ DESIGN FLOW
3. RAW WATER PUMP STATION
PUMP STATION ULTIMATE CAPACITY 60 MGD
CURRENT DESIGN CAPACITY 40 MGD
40 MGD PUMP INSTALLATION - 4 - PUMPS TOTAL WITH 3 ONLINE
4. RAW WATER MAIN TO RESERVOIR NO. 1
EXISTING RESERVOIR CAPACITY MG
EXISTING PIPE SIZE 30 INCH
PROPOSED PIPE SIZE 36 INCH
ULTIMATE CAPACITY 60 MGD
DESIGN CAPACITY 40 MGD
5. RAW WATER MAIN FROM RESERVOIR NO. 1 TO RESERVOIR NO. 3
EXISTING RESERVOIR CAPACITY MG
EXISTING PIPE SIZE 30 INCH
PROPOSED PIPE SIZE 36 INCH
ULTIMATE CAPACITY 60 MGD
DESIGN CAPACITY 40 MGD
6. RAW WATER MAIN FROM RESERVOIR NO. 3 TO RESERVOIR NO. 2
NEW RESERVOIR CAPACITY MG
PROPOSED PIPE SIZE 42 INCH
ULTIMATE CAPACITY 60 MGD
DESIGN CAPACITY 40 MGD
d-DWI design calculations-22 NOV 13
15 MGD UPGRADE SUPERPULSATOR
1

DAVIDSON WATER, INCORPORATED
WATER TREATMENT PLANT UPGRADE TO 30 MGD
DESIGN CALCULATIONS
NOVEMBER 2013
7. NEW RESERVOIR PUMP STATION
PUMP STATION ULTIMATE CAPACITY 40 MGD
CURRENT DESIGN CAPACITY 30 MGD
30 MGD PUMP INSTALLATION - 4 - PUMPS TOTAL WITH 3 ONLINE
8. FLASH MIX - NEW
BASIN SIZE
LENGTH 20 FEET 20 FEET
WIDTH 20 FEET 20 FEET
DEPTH 30 FEET 30 FEET
DESIGN FLOW 30 MGD 40 MGD
VOLUME 12000 CF 12000 CF
DETENTION TIME 4.31 MIN 3.24 MIN
9. SUPERPULSATOR CLARIFIER - NEW
FLOW 15 MGD 20 MGD
EFFECTIVE PLATE AREA 5664 SF 5664 SF
OVERFLOW RATE 1.84 GPM/SF 2.45 GPM/SF
10. DUAL MEDIA FILTERS
FILTER AREA
LENGTH 20 FEET 20 FEET
WIDTH 22 FEET 22 FEET
FLOW 15 MGD 20 MGD
TOTAL NUMBER OF FILTERS 6 EA 6 EA
NUMBER OF FILTERS WITH ONE OFF-LINE 5 EA 5 EA
FILTRATION RATE WITH ONE OFF-LINE 4.73 GPM/SF 6.31 GPM/SF
FILTRATION RATE WITH ALL FILTERS ON-LINE 3.95 GPM/SF 5.26 GPM/SF
11. CLEARWELL / CONTACT CHAMBER
FLOW 30 MGD 40 MGD
VOLUME 5 MG 5 MG
CALCULATED T-10 93.00 MINUTES 69.00 MINUTES
d-DWI design calculations-22 NOV 13
15 MGD UPGRADE SUPERPULSATOR 2

DAVIDSON WATER, INCORPORATED
WATER TREATMENT PLANT UPGRADE TO 30 MGD
DESIGN CALCULATIONS
NOVEMBER 2013
12. SLUDGE THICKENER
DIAMETER
SURFACE AREA
SLUDGE WASTE RATE
SLUDGE FLOW RATE
ACTUAL LOADING RATE
MAX LOADING RATE
13. EQUALIZATION LAGOON
VOLUME
NUMBER OF FILTERS
TOTAL FILTER AREA
BACKWASH INTERVAL
BACKWASH RATE
BACKWASH TIME
VOLUME REQUIRED
VOLUME AVAILABLE
d-I)WI design calculations-22 NOV 13
15 MGD UPGRADE SUPERPULSATOR
3
80 FEET
5,026 SF
2 %
600,000 GPD/SF
119 GPD/SF
300 GPD/SF
400,000 GALLONS
6 FILTERS
2,640 SF
48 HOURS
15 GPM/SF
20 MIN
396,000 GALLONS
400,000 GALLONS
80 FEET
5,026 SF
2 %%
800,000 GPD/SF
159 GPD/SF
300 GPD/SF
iTril

CLEARWELL TANKS
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p441
3OMGD
DISCHARGE
TO OUTFALL
RAW WATER
IMPOUNDMENT
LAKES
CHEMICAL ADDITIONS
U w
w cc
UI— w
Q'
Li_ 0 0 cLi }
J J J J
U 2 w O O
V)Q U Li V) 0-
30MGD
SOLID REMOVAL
PER WQ0031712
i1L
DECANT OR
SLUDGE
RAPID MIX
30 MGD
DT=4.31 MIN.
PROPOSED
SCREW PRESS
SLUDGE
THICKENER
119 GPD/SF
CHEMICAL ADDITIONS
PHOSPHATE —
SODIUM HYDROXIDE
FLOCCULATION
6 BASINS
PADDLE FLOCCULATORS
8400 GPM Average
DT=30 MIN
FLUORIDE
CHLORINE
CHLORINE
SUPERPULSATOR
CLARIFIER
2 BASINS
15 MGD
1.84 GPM/SF
SLUDGE
DECANT
9MG
30MGD
SEDIMENTATION
6 BASINS
8400 GPM Average
T50=217 MIN.
C
8
MIXER
15MGD
SED BASIN SLUDGE
FILTRATION
6 DUAL MEDIA FILTERS
3.95 GPM/SF
18 IN. ANTHRACITE COAL
10 IN. SAND
WHEELER UNDERDRAIN
SLUDGE
30MGD
TO SYSTEM
HIGH SERVICE PUMPS
FILTRATION
20 MULTI MEDIA FILTERS
4 GPM/SF
18 IN. ANTHRACITE COAL
10 IN. SAND
12 IN. STONE
WHEELER UNDERDRAIN
FILTERS 1-8, 13-20
LEOPOLD UNDERDRAIN
FILTERS 9-12
BACKWASH ON
HEADLOSS AND TURBIDITY
BACKWASH
CONTAINMENT
0.5MG
FILTER BACKWASH
15MGD
DAVIDSON WATER INC.
P.O. BOX 969
WELCOME, N.C. 27374
[phone]
DESIGN FLOW=30 MGD