November 25, Mr. Paul Kaspar, PE City Engineer City of Bryan Post Office Box 1000 Bryan, Texas 77802

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1 November 25, 213 Mr. Paul Kaspar, PE City Engineer City of Bryan Post Office Box 1 Bryan, Texas 7782 Re: Greenbrier Phase 9 Oversize Participation Request Dear Paul: On behalf of the owner, Carter-Arden Development, I wish to request Oversize Participation payment for costs associated with the extension of sanitary sewer lines to the Greenbrier Phase 9 Subdivision in the amount of $69,844. Please see attached exhibit detailing the cost determination. The proposed 24 sewer line along the southwestern boundary of Phase 9, as shown on the preliminary plan for this phase, is in compliance with the previous sanitary sewer analysis of the area that was provided with the oversize participation request for Greenbrier Phase 12. A 6 sanitary sewer line would have been required under normal development of this phase. Exhibit C shows calculations of the anticipated flows from the Greenbrier Subdivision to demonstrate the capacity of the 6 line. Therefore, the price difference between the 24 line and the 6 line is the basis for the over size participation request. If you need additional information, please contact me at your convenience. Sincerely, Jeffery L. Robertson, P.E. Vice President Engineering Attachments Exhibit A Sewer Map for Lines to Serve Greenbrier Subdivision Only Exhibit B Sewer Map for Line Sizes to serve Greenbrier and the Surrounding Area under Ultimate Conditions Exhibit C Sewer Line Calculations Exhibit D Cost Estimate for Difference between Proposed Sewer System and Minimum Required Sewer System Exhibit E Total City of Bryan public infrastructure costs for Phase 9 F:\198 - Pitman-Murphy Group\1 - Greenbrier Phase 9\Docs\OP Request\COB - Kaspar1 - OP Request revised.doc

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4 Exhibit C Greenbrier Subdivision Sanitary Sewer Analysis Line Flow Calculations Pipe Calculations From To Residential Commercial Flow From Node to Node Contributing Flow from Upstream Nodes Average Daily Flows (ADF) Infiltration (1% ADF) ing Factor Flows Size GPD per GPD per MH # MH # Lot acre GPD GPD CFS CFS CFS (in.) Inches % % fps Inches % % % fps Inches Material Inside Diameter Manning Friction ADF Min. Design ADF Ave. Daily Flow Velocity Ave. Daily Flow Depth Manning Friction Flows Min. Design Flows Actual for Existing or Designed Systems Pipe Check Flow Velocity Flow Depth A B D OK.. QQ B 27 7,29-7, D OK B LL - 7,29 7, D OK KK LL 15 4,5-4, D OK LL NN - 11,214 11, D OK MM NN 12 3,24-3, D OK NN PP - 14,418 14, D OK PP SS 18 4,86 14,418 19, D OK RR SS 18 4,86-4, D OK SS UU - 24,3 24, D OK TT UU 15 4,5-4, D OK VV UU 17 4,539-4, D OK UU BB - 32,574 32, D OK C G 16 4,272-4, D OK D F 27 7,29-7, D OK E F 22 5,874-5, D OK F G ,83 13, D OK G W - 18,156 18, D OK H J 8 2,136-2, D OK I J 15 4,5-4, D OK J V 15 4,5 6,141 1, D OK K M 12 3,24-3, D OK M U 9 2,43 3,24 5, D OK N P 16 4,272-4, D OK O P D OK.. P R ,272 4, D OK Q R 11 2,937-2, D OK R T ,743 8, D OK S T 14 3,738-3, D OK T U 17 4,539 12,15 16, D OK U V 17 4,539 22,161 26, D OK V W - 36,846 36, D OK W Y - 55,2 55, D OK X Y 15 4,5-4, D OK Z AA 15 4,5-4, D OK Y AA - 59,7 59, D OK AA BB - 63,12 63, D OK BB JJ - 95,586 95, D OK Sewer-OP.xls 11/25/213 Exhibit B

5 -T Exhibit B Greenbrier Subdivision Sanitary Sewer Analysis Line Flow Calculations Pipe Calculations I B ;:: "' E I EI: ~ ]\fanning Min. s u 2 ~ c u ;:: ~ i:i3 ;;::: u GPD GPD % % -,~--~--,, ,45 I ' -- ~ I 16 3,24 i.5 62,619 i o.9324 I 65,823 T ~9373 r - - ~-TQ:-o7s , ,67 ~~1_,L88 l.626,ijj H 68,886 I 4.26 ~,~ i.87 J 4,5 : 72, II 26,379J 4,272:.7 2:937 I , Ll6 K.5.58 M u.9.87 u v.29 v w x y 15 Ol.?;> Ol "O ~ z ~ ~?3 Average Daily Infiltration ing Inside Design Ave. ;; <!'. I From To "O µ;... ~ E Ex.;:: Q.."'O ~ ::i..., Size Material Flow Flows(ADF) Flow Flow,; o- E... z (1%ADF) Factor Flows Diameter, bo c "'- "E a z Velocity Depth ADF -~- w y.176 z y AA DD EE 12 3, FF I GG 26 6,942 12,816' I cc 18 4,86 ' 4, HH JJ I 15-Sewer-rEV.xls 1117/212 ExhibilB

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