Loading...
HomeMy WebLinkAbout7C, Final Draft of I&I Report ~ ~~HILLS City Council Agenda Packet Item: March 31, 2008 ~ ~HILLS Request for Council Action Prepared By: Dept.: Council Mtg." Date: Final Action Needed By: _ ~~i.s~i~~_ ~i_g~ ~_~_~il1~ering 3/31/08 Budgeted Amount: Actual Amount: Funding Source: the Inflow and Infiltration (1&1) report and provide staff with feedback on proposed 2008 action items presented. the Inflow and Infiltration (1&1) report and provide staff with feedback on proposed 2008 action items presented. PTRC: S)Jppoitlng Deicu,n"n!/;: (attach'ld) x Memo/Letter: Resolution No.: Ordinance No.: Engineering Recommendation: Attorney Recommendation: From Civil Engineer Kristine Giga dated March 25, 2008 x Other: 1&1 Report prepared by Chuck Janksi of Bonestroo; 2007 surcharge credit verification to the Metropolitan Council Environmental Services dated March 24, 2008; Manhole Inspection Map ~ ~ EN HILLS MEMORANDUM DATE: March 25, 2008 TO: Mayor and City Council Jim Willis, Interim City Administrator FROM: Kristine Giga, Civil Engineer Greg Hoag, Public Works Director SUBJECT: Presentation of Inflow and Infiltration (III) Final Draft Report BACKGROUNDIDISCUSSION Wastewater collected in the Arden Hills sanitary sewer system flows into main sewer lines owned and operated by the Metropolitan Council (Met Council), who collects and treats wastewater for the seven-county metro area. Inflow and infiltration (1&1) is clear water that makes its way into the sanitary sewer system and mixes with wastewater already in the sanitary sewer pipe, increasing the amount of wastewater requiring treatment. Infiltration is a result of groundwater entering the sanitary sewer system via cracks in the sewer pipes, leaky joints, or deteriorated manholes. The main source of inflow is stormwater that enters the sanitary system from rain leaders, sump pump discharges or foundation drains, none of which are supposed to be connected to sanitary sewer lines. The more rain that falls, the more inflow into the system. The capacity of Met Council's wastewater system is being consumed by 1&1, which, ifnot corrected, would restrict future growth and potentially cause the bypass of sewer flows into the Mississippi River. Met Council approved a surcharge program in February 2006 that requires communities with excessive 1&1 to pay surcharges on their regional wastewater bills. Met Council has notified communities with significant 1&1 problems. As communities are able to reduce the excess 1&1 with improvements to their sanitary sewer systems, the surcharge could be reimbursed. Met Council estimates that it would cost approximately $900 million to expand its system to treat the excessive flows. Met Council also estimates that if communities were to address the problem locally, costs would be much less, around $ 150 million. Met Council notified Arden Hills that the City exceeded our allowed 1&1 limit during a storm event on October 5, 2005 and that an annual surcharge would be imposed on the City in the \\Metro-inet.us\ardenhiIls\PR&PW\Engineering\2008\Council_ Actions\3- 3 J -08Memol&l.doc 1&1 3/25/2008 Page 2 amount of$100,100, beginning in 2007. As a result, the City hired Bonestroo to assist with a study that would begin to identify sources of 1&1 and determine appropriate steps to reduce the City's 1&1. Attached is a report discussing the existing sanitary sewer system, methods used in the study to date, potential 1&1 sources to consider, preliminary conclusions and recommended next steps. FINANCIAL IMPLICATIONS The MCES program, as implemented, includes an annual surcharge for a period of five years, which began in 2007. The City of Arden Hills has been surcharged $500,500, or $100,100 per year over the five year period. This annual amount has been included in the City's 2008 budget and in the Five-year Capital bnprovement Plan (CIP.) RECOMMENDED COUNCIL ACTION Receive 1&1 report and provide staff with feedback on proposed 2008 work plan. ~ ~~HILLS March 24, 2008 Mr. Kyle Colvin, P.E. Assistant Manager, Engineering Planning Metropolitan Council of Environmental Services 390 Robert Street North St. Paul, MN 55101 Re: Inflow and Infiltration (1&1) Surcharge Credit Verification for 2006-2007 Dear Mr. Colvin: The City of Arden Hills is submitting its surcharge credit verification information for work completed in 2006 and 2007. Attached please find the completed credit verification form, invoices and records of expenses incurred by the City of Arden Hills for 1&1 related work. Proposed total expenditures for 2007 exceed the surcharge amount of$IOO,IOO. The City of Arden Hills requests that the additional expenditures are made available for credit in 2008. If you have any questions or need additional information, please contact me at kristine.giga@ci.arden-hills.mn.us or (651) 792-7849. Sincerely, ~~~!(A./ Kristine Giga, P .E. Civil Engineer Cc: Greg Hoag, Public Works Director Jim Perron, Public Works Superintendent Jim Willis, Interim City Administrator Finance Department Mayor and City Council City of Arden Hills . 1245 West Highway 96 . Arden Hills, MN . 55112-5743 Phone 651.792.7800 + Fax 651.634.5137 . www.ci.arden-hiUs.mn.us Appendix 0: Surcharge Credit Verification Form Complete this form and its attachments to assure MCES that the community has spent the surcharge equivalent on applicable projects, approved by MCES, during the calendar year 2007 or 2008. To receive payment, send the completed form to: Mail: Assistant Manager, Engineering Planning 390 N. Robert Street SI. Paul, MN 55101 Fax: Attn: Assistant Manager, Engineering Planning (651) 602-1030 Community: ARDEN ttl L.-l-? Calendar Year in which Work was Performed: '2-00~ - 2.001- Was the work pre-approved by MCES? 0 Yes (Attach MCES letter) ~ No a) Public Facility Work: Attach a detailed breakdown of actual expenditures for the municipal system III program. Include only amounts actually paid during the calendar year. MCES may request additional documentation to verify expenditures. Include the percent of each projects costs that are related to 1/1 mitigation: Summary of Costs: -::r. ~ 1 S-rU.OY) AAlw MST6"f< 8A:tJ 111<\1'<..'-( sew e~ -relA~"\SINb I I2X:f'Ale . ~kL.) "-lA,~l-toL6 lJ,jspecn~> ANt> b) Private Property Work: Attach a detailed list itemizing the locations and repairs made on private properties within municipal borders. Summarize the type of repairs and applicable costs using the list below: Sump pump disconnections: $150 per dwelling = $ Foundation drain disconnections: $3,000 per building = $ Rain leader disconnections: $100 per single family dwelling = $ Rain leader disconnections: $3,000 per commercial dwelling = $ Service lateral repairs: $5,000 per repair = $ Describe Other Work: . '2. qo Total claimed for U10b -l.Q?1- (calendar year):: $ II'Ll ?9J . -- City or Township OfflclalfTItle: l-I ~ I , ~h \'J'\ ,HoC<.e"r Date Signed: :, \ l.S-j 01) Phone #: l1AIL'L uJo<1KS f)it2VTOR- 051- 7'1:), - TffL/7 Amount Eligible: $ MCES USE ONLY Form: ILVerification_200S Last update: 6/12/07 19 OJ "5 .r:. c '" E <3 ~'" ::>,.; [LOo ....J-:f:-<::t ;:~:;U) "''''190 tf) ~~~g E LLooO-- Q) -l::;..c(o Eo 0 C W o..!:{\Jc E ",-"E'g o NCOOC o (()MNW OIONOOOO(")O 1.0("')("')0000......0) tON-<::tNooomM lON-.::t<OO"<:tt--coco lOl'-...-<ONo;:;:tOIOM -COcO~"<;f""N(")CO..jN Cf;fltFJ-f::/700(O..--tFJ-f:fiT'"" ::J WOO- T'"" o .,. E <( B "0 ., c ~ 0 Q)::; ~ .. -'" ~~ ~ ~;; cf;f?-cf.cf.cf.cf.cfcf.~ OOOOOOOOL.. oOOC>OOOOj ...-...........-...-..--...--...-- ..-.~ "0 C ., a. X .. .. - o I- 121 "- '-:~ Igl~ ~ Q) Q) <D <D U) "-.....1- ;; ~i!!c(J) Q. 00-- c X ..c...cmo Q) C C 2,- _ m ro "- t5 o 1 Q E E OJI!!!'m OJ c c "- "- 5'1 (';)1 ~ > o '~.2.E~.~ ~~ "'0.- 2': Q) ~ ~I - ill Q) b -0 ro col C - - w .~:JE'L:'croooc ~W3:22:g~-2E C1J::;cocoCOrororou C~U:::22(/)22<( ... o o N . co o o N C o c vi OJ .~ ro ~ o .0 '" --' _21 C :;:::::; (I) .s ~~ __~ :i )-0 ~ ~~ "'1i)s E EOJ g =:;; IS. L9 "" .g ~ m t.~ I.~ ~ ooroS<D~ ~~ ugoEg1ij~~cr ~(/)~l])"""'___""",_ g g.~ ~ ~lil~I_~I.~ U<!l2Z00000 c/l ~ o - "E 1( "' "' ., ~ ::> '" "0 C 1:: X w 2335 Highway 36 W StPaulMN55113 T,,6S1-636~ Fax 651-636-1311 October 29, 2007 Invoice No: Invoice Am!: 149764 $3,232.00 li'VWVtI.booestroo_com City of Arden Hills 1245 W Highway 96 Arden Hills, MN 55112-5743 Received OCT 31 Z007 .. Bonestroo City of Arden Hills Professional Services from June 17, 2007 to October 20,2007 Project 000353-07103-0 Infiltration Inflow Analysis Data Gathering and Evaluation Total Labor Hours Rate Amount 5.50 16000 880.00 300 94.00 282.00 625 88.00 550.00 1475 1.712.00 T atal this Phase $1.71200 Project Manager Engineer Engineer Develop Metering Program Total Labor Hours 9.50 9.50 Rate 16000 Amount 1,520.00 1,520.00 Project Manager Total this Phase $1,520.00 Total this Invoice $3,232.00 Hourly Totals Current 3,232.00 3,232.00 Prior 0.00 000 Total 3,23200 3.23200 . i V ,\V @v -{4,,' __'"1 llr"<O ',\\{ / " "\\\ Billings to Date JoV ~: 09_- '1"10.Y/ - I/-).r '),r,. 7 i l'),-, of::--- ~ November 27, 2007 Invoice No: Invoice Amt: City of Arden Hills 1245 W Highway 96 Arden Hills, MN 55112-5743 Received NOV 3 {I Z007 City of Arden Hills Professional Services from October 21, 2007 to November 17, 2007 Project 000353-07103-0 Infiltration Inflow Analysis 150828 $1,56350 2335 Highway 36 W SL Paul MN 55113 Tel 651-636-4600 Fax 651-636-1311 \NIIVW.oonestroo.mm .. Bonestroo Data Gathering and Evaluation Project Manager Engineer Hours 1.00 U5 3.25 Total labor Rate 160.00 94.00 Amount 160.00 211. 50 371.50 $371. 50 Report Preparation Project Manager Engineer Hours 2.50 900 11.50 Total labor Total this Phase Rate 160.00 88.00 Amount 400.00 792.00 1,192.00 lotal this Phase Total this Invoice Billings to Date Current Prior Total Hourly 1,56350 3,232.00 4,795.50 Totals 1,563.50 3,232.00 4,795.50 $1,19200 $1,563.50 January 25, 2008 Invoice No: Invoice Am!: 152875 $1.760.00 City of Arden Hills 1245 W Highway 96 Arden Hills, MN 55112-5743 Received FE8 - 1 2uD8 City of Arden Hills Professional Services from December I, 2007 to December 31,2007 Project 000353-07103-0 Infiltration Inflow Analysis Report Preparation Project Manager Hours 11.00 11.00 Amount 1.760.00 l.760.00 Rate 160.00 Total labor T otalthis Phase Total this Invoice Billings to Date Current Prior Total Hourly 1.760,00 4.79550 6,555.50 Totals 1.76000 4,795.50 6,55550 AU imaic~ af-2 due ar.d paY3~je ,':ithi" 50 day,;. ~:1t2;c':: ~;:il1 hi: .charge::! .3i .or; a~::t;d! ra,;; of 18% Oil all amOU:ll5 nat paid withi;'] 30 dar,. Please remit all invoice payments to our lockbox: Bonestroo P.O. Box 1521, Dept. #1156 Minneapor~, MN 55480-1521 All other correspondence should continue to be sent to your !Q{a! Boneslroo office 1135 Highway 36 W StPaulMNSS113 Tel 651-636-4600 Fax6S1-636-1311 vvww.bonestmo.com .. Bonestroo $1,760.00 $l.760.00 INVOICE ilww.mvtl.com lABORATORIES, Inc. 1126 NO. FRONT STREET P.O. BOX 249 NEW Ut.M, MN 56073-0249 PHONE (507) 354-8517 FAX (507) 359-2890 WE ARE AN EQUAL OPPORTUNITY EMPLOYER A SERVICE CHARGE OF 1 'Jz% PER MONTH (18% APRJ. will be made on balances due beyond the terms stated -on the invoice. Minimum charge $.50. BILL TO: We accept VISA & MasterCard REPORT TO: ARDEN HILLS, CITY OF ACCOUNTS PAYABLE 1245 W H(~Y 96 ARDEN HILLS MN 55112 11ROEN HILLS, CITY OF ACCOUNTS PAYABLE 1245 (~ Hl~Y 96 ARDEN HILt.S MN 55112 TOMER NO. iNVOICE NO. iNVOICE DATE DUE DATE TERMS CUSTOMER P.O. NUMBER 1437 362195 8/29}e'7 9/13/07 NET 15 DAYS ARDEN HILLS WORK ORDER NO. REPORT DATE ANALYTICAL LABORATORY 31.00451 8}29}07 NEW ULM INDRGANICS LAB .. TESTS DESCRIPTION LIST PRICE DISCOUNT AMOUNT 1. Tech Time T17023 1.1 2,011.50 2,011.50 1 Mileage M35023 11 321.30 321. 30 1 Supplies & Expenses S97023 11 1.52.55 152.55 1 Equipment Rental E70023 11 6,237.00 6,237,00 SALES TAX DISCOUNT AMOUNT DUE .00 .00 8,722.35 TO ENSURE PROPER CREDIT, PLEASE DETACH & REMIT THIS PORTION WITH PAYMENT 1437 ARDEN HILLS, CITY OF 362195 DUE DATE 9/13/07 AMOUNT DUE 3,722,35 PLEASE MAKE CHECKS PAYABLE TO MINNESOTA VALLEY TESTING LABS m ~ NORTHERN WATER WORKS SUPPLY BLAINE'MN. 763-560-5200 Fax 763-560-1799 An Equal Opportunity Employer Invoice iilllm!@1!Ml!!mtriu 07/20/06 REMIT TO: PO BOX 1070 FARGO NO 58107-1070 1 BILL TO: CITY OF ARDEN HILLS WATER DEPARTMENT 1245 WEST HIGHWAY 96 ARDEN HILLS, MN 55112 SHIP TO: CITY OF ARDEN HILLS WATER DEPARTMENT 1245 WEST HIGHWAY 96 ARDEN HILLS, MN 55112 J4AR27R200 ~7 X 2 HDPE MH ADJ RING 27R200 J4ARSEALTUBE IDPE MH ADJ RING SEALANT 10 OZ TUBE 40ea 40ea 3.72 148.80 1 R.EC~~'-:: I j I CiTY Of ,~,RDiN HH LS JUl 2 7 2006 I~r >tt~ {}--:)..70 S~"iL ~f voice is due y 08719/ 6. ~s: Due Net 30 Days from date of Invoice. A SERVICE CHARGE is computed by a periodic ~ of 1.5% per month. This is an ANNUAl PERCENTAGE RATE of 18%. :redit wi It be allowed for goods returned without permission. Returned goods must be ~aleabte condition. A re-stocking charge will be made on all g.oods returned far jit. Ue are not responsible for damage in transit. Claims must be filed with carrier_ e billing inquiries dial 1-888-873-5685 Subtotal S&H CHGS Tax 1210.40 0.00 78.68 Amount Due 1289.08 s NORTHERN WATER WORKS SUPPLY BLAINE MN 763-560-5200 Fax 763-560-1799 An Equal Opportunity Employer Invoice iMmiHiMltilltil6r#HMi .". HiiMlmml!%'i~lM! 0 8 / 0 1 / 0 6 S 0 1 0 3 6 9 9 1 0 0 1 REMIT TO : ;;iit~#tiM'm!F: PO BOX 1 0 7 0 FARGO ND 5 8 1 0 7 - 1 0 7 0 1 Blt.l TO: CITY OF ARDEN HILLS WATER DEPARTMENT 1245 WEST HIGHWAY 96 ARDEN HILLS, MN 55112 SHIP TO: CITY OF ARDEN HILLS WATER DEPARTMENT 1245 WEST HIGHWAY 96 ARDEN HILLS, MN 55112 .......'w.._.'........._........m.. m___ _ ...... - . ...... . .. . ;:':::':0;"..-....:...;...,.....;_..:_._._:::_,_......:.....:... 34AR27R200 27 X 2 HDPE MH ADJ RING 27R200 34ARSEALTUBE {DPE MH ADJ RING SEALANT 10 OZ TUBE 20ea 20ea 3.72 74.40 l___ _ -',,,.. ... 4 nnc . - ::: l..uvU . ,-. .,- ~q ! : i.-~~_____~~.__..~_ 1:.."",,~ i\~~ J.."d-,O S~..>n_n.. p voice is due y 08731/ 6. ~s: Due Net 30 Days from date of Invoice~ A SERVICE CHARGE is computed by a periodic ~ of 1.5% per month. This is an ANNUAl PERCENTAGE RATE of 18%. :redit will be allowed for goods returned without permission. Returned goods must be ;aleable condition. A re-stocking charge wilt be made on all goods returned for iit. ~e are not responsible foc damage in transit4 Claims must be filed with carriec4 , billing inquiries dial 1-888..873-5685 Subtotal S&H CHGS Tax 645.01 0.00 41. 93 Amount Due 686.94 s NORTHERN WATER WORKS SUPPLY BLArNEMN 763-560-5200 Fax 763-560-1799 An Equal Opportunity Employer Invoice itiNNl]ilVilji*Jllmlt'tt'""""", ......................_._--..-......-... 08/15/06 REMIT TO: PO BOX 1070 FARGO NO 58107-1070 1 BILL TO: CITY OF ARDEN HILLS WATER DEPARTMENT 1245 WEST HIGHWAY 96 ARDEN HILLS, MN 55112 SHIP TO: CITY OF ARDEN HILLS WATER DEPARTMENT 1245 WEST HIGHWAY 96 ARDEN HILLS, MN 55112 """"""""',,"""-'"'''''''''' ~;:;}~;;~i:~;~~~:~,~~::::;:;::;:::;;:;: J4AR27R200 ~7 X 2 HDPE MH ADJ RING 27R200 l4ARSEALTUBE [DPE MH ADJ RING SEALANT 10 02 TUBE 48ea 48ea 3.72 178.56 REC-U ,~~ t:1V~'~ . AUG 2 1 2006 CITY OF ARDEN HILLS 'S....~ ~~ Qwfhe5 t\<!C,'*L:;l.-:J.-7v ~ ~I;) voice is due y 09714/ 6. IS: Due Net 30 Days from date of Invoice. A SERVICE CHARGE is computed by a periodic ~ of 1.5.% per month~ This is an ANNUAL PERCENTAGE RATE of 18%. TecHt will be allowed for goods returned without permission~ Returned goods must be ,ateable condition~ A re-stoclcing charge witl be made on all goods returned for I1t_ We are not responsible for damage in transit~ Claims must be filed with carrier. . billing inquiries dial 1-888-873-5685 Subtotal S&H CHGS Tax 443.96 0.00 28.86 Amount Due 472.82 NORTHERN WATER WORKS SUPPLY 1694 9lST AVE NE BLAINE MN 55449 763-560-5200 Fax 763-560-1799 Order #: Ord Date printed: Page # ** PICK TICKET ** S01046050.001 09/08/06 10:07:28 25 SEP 2006 COT 1 of 1 30ld To: 2646 CITY OF ARDEN HILLS WATER DEPARTMENT 1245 WEST HIGHWAY 96 ARDEN HILLS, MN 55112 Ship To: 2646 CITY OF ARDEN HILLS WATER DEPARTMENT 1245 WEST HIGHWAY 96 ARDEN HILLS, MN 55112 Job Name Ship Date 09/08/06 Ship via WC WILL-CALL Warehouse Shp 3 Ent 3 :::Ustomer PO >HKE -lri ter C.SCHOEPK Freight PPA salesperson Todd Phillips Ordered By MIKE Contact# 651-634-5120 Ordered Shipped Product Description Net Prc Ext Pre 75ea 75ea 94AR27R200 27 X 2 HOPE MH Lec: -- Secondary Loc: 13 .27 995.25 ADJ RING 27R200 Pn: 15746 Wgt: 432.75 Y34 25ea 25ea 94AR27R400 27 X 4 HDPE MH Loc: -- Secondary Loc: 23.87 596.75 ADJ RING 27R400 Pn: 15747 Wgt: Y34 267.75 SUBTOTAL SALES TAX%- 1592.00 103.48 *** Thank you for your Business *** Total J..J!1.0unt 1695.48 OO{P'W 'i1led by . ~heeked ~stomer S1gnature: \ by Pieces Total Weight: 700.5 Date: ___/___/___ '0 credit will be allowed for goods returned without permission. Return goods Bust be in saleable condition. A re-stocking charge will be made on all goods ~eturned for credit. We are not responsible for damage in transit. Claims must )e filed with carrier. .. Reprint .. Reprint .. Reprint .. Reprint .. .. E m~ 0 ~. u ;!O oi 00 C M 0 ~. '" O. E .- ~- . 0"" u -g~ ~ E c. ~ ~~ ~ "0 ~ . . "0 X OC o. . . C ~ 0_ M~ ~ (fl~ N '" 0 00 ro ID :;; "'- . C 0 '" E . 0 0 0 '? N m N m 00 ro ro :;; "'- 0 N :;; ID Z ~,; '" C~ "' _0 L' .' m -. " .. ~. I O~ " ~~ ~C " .. u >. C . =E '" .- ~c -. 0 .. 0 0" M 0" ~ ,. C" TI _0 > o~ in :;;0 . .- .. e 0> 6 0= <L .- .1' ~ C. e =- C. . O. 0 ~ J .. ID o. N Ell: 0 o. N e. , 0 00 0 .~ '" 1--\ E. I- ~: 0 -\- 0 => ~ r ~. 0 E" .< 0 rl, ,,, a: ~ ,<L <L i" ~ '. w G \ 0- z " _c < 0 a CE I- o. '" m- '" 02 ~" w 0 ~Iil'd 1t:llOl CElIiIS'I'ONE PR.ODUCTS CO. CONTRACTOR SUPPLY !>IV/SION 2023 CIlNTRE POINTE BLVD., l:lOll MENDOTA HEIGffTS. loIN 55120 PboIlO: 6$1-611.9292 ~;6$1-1II8-0124 IlEMITPAYMENTTO: CEMSTONE PROOIJCI'S COMPANY M.t:162 P.O. 80. 1414 St. Paul. MN 354>>-1414 ~f'81O tNVOIO!ANCJ...Ifr k. '" ARDEN IUl.LS. aTY OF 1245 WllSTHIOHWAY96 AllDBNHILLS, MN 55112 INVOICE , " I . , o ARDEN HIllS, CITY OF 1245 WllST HIGHWAY 96 AlU>EN HILLS, MN SS112 QfIIeut ohIak1fU box 'your.,... it ~ Md...... MY dtange(.. on u............. :',. ~'.': ':~i.. . ..~. . ~~~t;.~. .....,. ,t,if", ..~~r -"~f' ~. .,~Oo' "~t '. ""':', oft " .:t: -',' ~: - ". ." ,_ i,\. . ~:., " ~1l. .,,\-. Itl... '~r.':' , . , 1.01 , ot. i 1\1111\0;: " I:ol '! , , '. ~ . .i {..... i .:' ., I oj. J .' : :':" ::] " .: J;: h ;r!. 'J ;~ .:". ,. ., ~.:.: ..' P1Maa ~n Ihlf QOtion...r. \tOW p&VI'MftL ~ aMok QIYIlbIt tel; CEMSTONE PAOOUC'fS cc:.: .'.~. t~,.,~~ :)j~."'BA-"'. 27INDlASlNWAU.' '.'. ':: ~'JWIR . ,,~~ .,. ., 0 ;ffiSIW:ANT>>CTN .,~,.. ,. "::i~ 'AA '\~;. 1;t:,:;,,' . ':f;::':. ,t.: . j~t ;;\- ~~\~'::: i.'" . ':r.F;:' . ~'L:. .~,' . ~ ,.;'{'" :.'-. .: ,~. .f:-: ': ~ ~ ',..;. TVSE I,'. .,~. .~( ....',... """ ;y.;'. '~< . "-. "';'" ~y~ J.;" .~r; , ~:. .,;;.' :~ " J?;:\ '.: w.'.... :'" ;! '~;;' 100. . " , , ".i. s .sJ~:~ ~ ~,~~~t 'l ,.....:d: ': ,:t~ "a',' .''', : ~'~l . 'S;llr:: ~~ ~ f;.: . . 1;.1, '~i" ,,~, 'l, :':~'::JI!V,': .' '}'lii' ,':11-: . ;"~'~"" " ' '-' .:. f~ ~' '. t.l~~~ :;,;/i -It ~;'1'!' ; :;:W' :. .~If~i, , :;,j',,; '.' '.' '!" .' '. ."",< . :'::>~1' ',,'" ': ~: ,~ II.,~ .' . , ,. )i .., .' ",' .( ,. !} '::-:: ....._--.. ,..,. ""Mee CMf'tt NIt, at Dtrl f ~... It ww...,~ r ~~Mlft Mr................ ~...... ...., -~ ...... tit ..... ..............."""..,.....1ftIII .......,.. CEN$TONI:: ftACOUCT$ 00.' 2Oa5 C.mr. Palre.8I'V'lf., 1:10O "M4lndola~. MNSSl20 < (liS1} .... .1-8OOCetn1'OMl " (66t) 8fe.012" Few. www.mYOlft\ltOnt.<:Qm C'OI'-J .:....:.;.));j.. . .~. ro. ..__.... ._..... (0 o o cnN s::: - ._ T"" =("')0 ._ T'" lll..s:::. tJ)(.)(O =~o :.:2:'0 . Q) s::: .-- Q) T"" e "E ~ a.. <( ta ~ s::: ta .., .... (I) (I) c: .- m c: w :~ o rG - o I- N ..,. ci It) ..,. th o It) ClO (0 o>g 0 0 CN .- ~O 0 0 - 0 0 - 0 ~ .- m M . (0 f/) Q) 0 - C - - .- :J 0 :c ~ Q) ....... 0 0 0 0 C . 0 0 0 0 0 Q) ~ I.. "0 ll. C'l N L!) 10 - I.. .- <3: I.. Co <3: <<l - 0 0 0 I- 0 0 "0 (V) (V) c (J) III ... C C> c 0 l/l ... ... (J) (J) (J) D- c Cl III C C W 0 :ij ":; "0 "0 U III III III - - 0 0 l- I- <Xl 00 0 0 00 OJ O'l "<t "<t .~ I L!) 10 <0 CO Il) 0 0 <0 CO 0 .,- ..... (V) (") ..... (,S- (,S- (,S- OJ OJ C'l L!) <Xl C'l (V) I'-- CD ff7 0 0 N 0> - s:: 0 a -- M 0 a - - ~ ~ a -- m Q) . ..a CD tn E 0 - - - -- Q) 0 :J: - Q) a.-_ a 0 s:: Q) 0 a 0 Q) en ~ to LO "0 a.. , ..... ~ . <( ~ >- - III ::::J - ..., 0 a I- a "0 (") C III ... C> ... Q) Q) c Ol c W oS; U III - 0 I- to co '<t (J) t-- LO co "'" 0'1 t-- U') co "'" 0'1 t-- ff7 ff7 ~ (J) (J) N to ~ ~ ~ 0) 0) N L() I (0 0 ~ 0 N C)T"" eM 0 .- r.. 0 0 - Q) 0 - T"" .- .c OJ . E (0 rn 0 - Q) - - () .- () :c Q) Q) C ...... 0 0 e 0 0 0 Q) . r.. n.. ('") M "C T"" r.. r.. <( Q) .c 0 l\l - 15 () 0 ... 0 0 "0 ('") C l\l ... G ... <II <II C Cl C W > () l\l - 0 ... I'-- I'-- ."", 0) en en co co co L() 10 10 ...- ...- .... I ...... 0 0 C>~ t: T"" .- MO - - .- ..s::or:" III CJ<O II) s...0 - ctl - - .- 2 CJ :::c Q) . '- t: T"" 0 Q) s... "0 ~Q. s... <( ctl ::J t: ctl ..., '-.... III '~I-'r' o I- "C. J:: III 1iioi', C>' (") (") N '<t I'- I'- 0 I'- <0 <0 ....... I'- to It) '<t 0) to It) I'- N ....... ~ ~ ~ 0 ..- I'- to ~ 0 ii:: c: - t-- 06 C)g C:N c: 0 -- 0 0 - - -- a - 0 - -- m (II) C'O "- t/) Q) - - - c: it: - -- :::J c: J: J . to It) 0 c: I'- I'- 0 Q) T"" 0 '<t "'0 T"" Ol 0) ....... - . "- -- CO <( "- 0.0 <( - (J (ll Q) - o. -~ ex:> I-- 0 "- C\l "0 a.. (") t: <Il (ll t: ... t: C> 0 III ... ... <Il <Il <Il a. t: Cl (ll t: t: 0 W ;e "S; "0 "0 U <( (ll (ll - - 0 0 I-- I-- ~ ~ ~ 0 ..-- I'- lO 3: 0 ,..... ij: ~ 0 c: 0 N 06 0) - c: c: 0 0 0 M 0 0 0 - - .- 0 0 .- I- - m Q) CO .0 I- In - E - - 't: - .- Q) c: :c - - C. I 0 0 0 c: Q) 0 0 0 Q) U) 0 C') (") =0 T"" ..-- ....... (") l- I I <( T"" CD 0 >- - - 0 III :;j Q) ....' .., '0 '-' co .... 0 l- N :'0 0- C') .1::' QI .~ ~ s:: (.I). s:: 0 Ul ... ... QI QI QI Q. s:: Cl lI:l s:: s:: 0 W - :~ '0 "tl U <( lI:l lI:l - - 0 0 l- I- o C') N ~ I'- o (") N ~ I'- (") o N 00 ....... o N ";t ..- ..- o N -.:i .... .... o N -.:i ~ ~ tI)- tI)- ~ r--. 0 0 'i: 0 e N - - ~ O)T"" eM e .- I- 0 - Q) - .- .- ..0 .... CO ca E l- (/) .... Q) - - ~ - 0 .- e J: Q) e C I 0 Q) I 0 0 " T"" ...- N l- I <( I- co Q) 0 ..0 .... 0 0 III .... Q) 0 ....,:... ..... 0 0 0 .... I- "'C 0- s:: III ... C) ... lJ) lJ) s:: 0'1 s:: W :~ u III - 0 .... Report 2!QQ~lnfiltration I Inflow Program City of Arden Hills March 2008 Project Number: 353-07103 .tt Bonestroo City of Arden Hills March 2008 2335 Highway 36 W St. Paul, MN 55113 T,1651-636-4600 fax 651-636-1311 \iVIf{'N.bonestroo.com March 17, 2008 .tt Bonestroo Ms. Kris Giga, PE City of Arden Hills 1245 W Hwy 96 Arden Hills, Mn 55112-5743 Re: 2007 III Program City of Arden Hills Bonestroo File No.: 353-07103-0 Dear Ms. Giga, We are pleased to present the City of Arden Hills with this report on the 2007 Infiltration/Inflow Program. This project consisted of an initial sanitary sewer collection system analysis effort with the ultimate goal of reducing the amount of clear water in the City system. This clear water results in MCE5 charges for treatment in addition to a surcharge for the peak flow rate. Based on the analyses completed we have provided some guidance subsequent analytical steps and identification procedures, which can then be followed by rehabilitation of clear water sources. These are basic steps and will be subject to future modification and adaptation as more data are developed. The City's goal of III reduction will require a long term commitment to continuously observe conditions and rehabilitate sources as they are identified or they occur. Thank you for the opportunity to work on this project and get to know some of the City staff. We are available to discuss the contents of this report with you and other interested parties at any mutually convenient time. Sincerely, BONESTROO CV\~~. Charles Jans{} Project Manager I hereby certify that this Report was prepared by me or under my direct supervision and that I am a duly Licensed Professional Engineer under the laws of the State of Minnesota. Cha~~~' Date: ~~.Ilo8' Reg. No.: 14596 Page 2 of 12 City of Arden Hills March 2008 I. Introduction and Purpose Infiltration I Inflow (III) is defined as clear water that enters a sanitary sewer system. Infiltration is clear water that seeps into the pipe network from groundwater, and Inflow is clear water that is diredly related to rainfall or runoff events. III is a term used to describe all clear water without attempting to differentiate its source. This clear water does not require treatment until it is mixed with the wastewater already in the sanitary sewer pipe. Once it is mixed, the combined flow must be conveyed to a treatment facility for treatment before it can be discharged back into the surface water network. The III in the system can increase the normal flow in the system enough to stress the conveyance capacity of the pipe network, pumping stations, and the wastewater treatment facilities. In the seven county metropolitan area, the Metropolitan Council Environmental Services (MCES) provides an interceptor sewer system to coiled the wastewater from over 100 communities and convey it to one of eight MCES wastewater treatment facilities located around the metropolitan area. Communities own and operate their own local sanitary sewer systems to coiled the wastewater from individual buildings within their service area. Any clear water (III) entering a local colledion system is conveyed to and through the MCES system and diredly impacts the available capacity of the MCES interceptor and treatment facilities. The Metropolitan Council appointed a Task Force to identify solutions to the regional III problem. The Task Force worked from April 2003 to May 2004 and developed recommendations which were adopted by the Metropolitan Council as Policy in 2004. The Policy established the III Surcharge Program that is now in effed with the intent to avoid "hundreds of millions" of dollars in regional infrastrudure costs. The MCES currently monitors wastewater flows from all the tributary communities in the service area. With the III Surcharge Program an additional step was initiated to monitor peak flow conditions. Briefly, the program establishes a three year average flow for each community or "metershed" within the system. A peaking factor (multiplier) is applied to the average flow to determine an allowable peak flow. The peaking fador was previously adopted by the MCES for design purposes and it ranges from 4.0 for average flows less than 110,000 gallons per day (gpd) to 1.7 for flows over 30.0 million gallons per day (mgd). The MCES reviews hourly flow data from each meter during runoff events and compares the actual "peak hourly" flow to the allowable peak flow. If the actual peak is higher than the allowable peak, the extra flow is considered "excessive" and subjed to the III surcharge rate of $350,000 per mgd (this rate is annually increased by an inflation fador). The 1/1 surcharge is calculated for the highest peak recorded by the MCES and the surcharge amount is subdivided into five (5) years of annual payments. If a greater peak is recorded in the five year period, the surcharge amount can be recalculated and increased for the remaining years in the 5 year program term. Surcharges began in 2007 and will run through 2011. The City of Arden Hills is subdivided into three "metersheds" for measuring and recording wastewater flow. The combined total" excess" peak flow of these three metersheds was 1.43 mgd on October 4, 2005. Using this peak flow rate, the City's III surcharge was calculated to be $500,500 which is to be colleded at an annual rate of $100,100. The City has the option to pay the surcharge amount to the MCES, or make III redudion improvements to their system that will diredly off set the surcharge amount. If the City expends less than the annual surcharge amount, the balance will be colleded by the MCES and held in an account for future III improvement work. At the end of the five year program if there are any funds remaining in the community's MCES account, they will be turned over to the MCES as a "demand" charge and the MCES will use the funds for regional system improvements. At the end of the live year III Surcharge Program, the MCES will continue annual charge communities for peak flows in excess of the allowable flow, but the funds will go diredly to the MCES budget and will not be available to the Community for III redudion efforts. The goal is to make enough III improvements between 2007 and 2011 to eliminate the excess peak flow and therefore eliminate the III surcharge entirely. Page 3 of 12 City of Arden Hills March 2008 The purpose of this study and report is to begin the process of quantifying the III in the Arden Hills sanitary sewer system, isolating areas with the most significant problems, and preparing a plan of action for additional work to identify and remove sources of the III in order to eliminate the need for the MCES III Surcharge in the future. II. Background According to the Metropolitan Council Water Resource Management Policy Plan, the City of Arden Hills is expected to grow in population from 9,652 in 2000 to 22,500 in 2030 and grow in households from 2,959 in 2000 to 8,000 in 2030 (Note that the current Arden Hills Comprehensive Plan, which has not been adopted yet, anticipates a 2030 population of 13,500 people and 4,600 households. The reduction is due to a less aggressive development schedule for the TCAAP Area). This growth will increase the demands on the local and regional infrastructure including the wastewater collection and treatment systems that are the subject of this report. Wastewater flow from the City of Arden Hills is measured and recorded by the MCES at four separate meter sites (MOS1, MOS2, M054, and MOS9) located as shown on Figure 1. The existing Arden Hills sanitary sewer system includes approximately 232,300 feet of 8 inch to 21 inch diameter sewer pipe divided into four districts or "meter sheds" as shown in Table 1. Table 1 - Sanitary Sewer Inventory Meter Number Range of pipe diameters Length Comments On) (It) M051 8"-18" 66,100 M052 8" 8,900 M054 8"-21" 71,300 M059 8"-21" 82,600 Unmetered (lS 7) 8" 3,400 Total 232,300 The total wastewater from the City of Arden Hills is estimated by summing the total flow {rom each of the four meter5 and adding an estimate for the un-metered area served by lift station 7. The annual average daily flow5 for the metered areas for each of the past three years are listed in Table 2. Table 2 - Annual Averaoe Dail Flow bv Meter Shed in mod Meter Number 2004 2005 2006 MCES 3Yr Avg Allowable Peak M051 0.448 0.432 0.435 0.44 1.54 M052 0.038 0.039 0.038 0.04 0.16 M054 0.198 0.197 0.183 0.19 0.27 M059 0.317 0.312 0.286 0.32 1.15 Total 1.001 0.980 0.942 0.99 The annual average daily flow has declined slightly each year during this monitoring period. During runoff conditions following a rain event or snowmelt period, the flows increase markedly due to infiltration and inflow (III) entering the sanitary sewer system. In September 2007, the City wastewater flow peaked in response to a 1.83 inch rainfall event. The peak hourly flows recorded at each MCES meter site are listed in Table 3. Page 4 of 12 City of Arden Hills March 2008 Table 3 - Peak Hourlv Flow in mod followina 1.83 inch rainfall event on Seotember 19,2007 Meter Number Peak Haurlv Flow Rate in mad M051 1.20 M052 0.10 M054 0.57' Ma59 US' "Note: Calculated peak flow Tate exceeds allowable flow listed in Table 2 III. Temporary Flow Metering Temporary flow meters were installed in three manholes to subdivide the meter sheds of Meters M054 and M059 in an attempt to isolate III flows to smaller areas and focus rehabilitation efforts. The locations of the temporary meters are shown on Figure 1. The temporary meters consisted of a transducer placed in the flow channel, connected to a flow meterl data logger. The flow meter collects readings of flow depth and velocity from the submerged transducer. These values are then input into a formula and a flow rate is estimated. The three temporary flow meters were installed in the system from July 19, 2007 to August 29, 2007. This period was generally dry; however 2.05 inches of rainfall were received over a two day period on August 27 and 28, 2007. The flow data from the temporary meters are summarized in Table 4. Table 4. - Summrnf Temoorarv Flow Meterlno Data in mad Meter 1 Meter 2 Meter 3 Drv Weather Flow (Sf23/071 0.42 . 0.07 0.13 Peak Hourly flow (S/28/07) 1.15'" 0.15 0.27 "Note: Temporary meter number 1 was Installed to diVIde the Meter 059 Meter Shed and attempt to isolate pos$jble :/1 sources. This meter was operating for about 8 weeks so no long term average flow data are available; however, some dry weather and peak data are available for evaluation. The flow data recorded at meter 1 suggest flow rates in excess of those recorded at the downstream meter M059 and therefore the data are considered unreliable for comparison at this time. IV. Data Analysis The flow meters provide basic flow quantification and can be used in a number of ways to estimate an III quantity and make some predictions about possible sources of the III based on the flow patterns. The data can also be combined with other available City data to prioritize areas and maximize rehabilitation efforts. The data analysis included a number of steps as described below. The actual analysis for each" meter shed" is presented in a series of Figures in the Appendix, and the results are summarized in Table 5. Background Data. a The estimated number of "Residential Equivalent Connections (REC)" and the length of the sanitary sewer tributary to the meter location were obtained from the City graphical information system (GIS). a The Monthly Flow data from the past three years were obtained from the MCES for their meters. a Data from the temporary meters were compiled. Parameters for (omparison a Estimate annual III volume and treatment cost using "base" flow analysis . The average daily wastewater flow from January is assumed to be a "base" flow that includes a minimal amount of infiltration. . The average daily flow from January is subtracted from the annual average daily flow and the annual III volume and treatment cost are calculated. a Per Connection flow rate o The annual average daily flow, January daily flow, and the peak month daily flow are divided by the number of Equivalent Residential Connections (ERC). Page 5 of 12 City of Arden Hills March 2008 o Estimate III rates and per connection contributions using hourly flow data and early morning minimum flow rates. . In general, the flow in a sanitary sewer during the early morning hours (3:00- 5:00 AM) is a reasonable estimate of infiltration because there is minimal sanitary use of the system at that time. This estimate can be affected by water softener recharge cycles or commercial! industrial uses that continue throughout the night . The early morning flow rate for a dry weather (non-rainfall) day is subtracted frorn the total flow for the day to calculate an average daily "wastewater" flow for a dry weather (non-rainfall) day. . The estimated infiltration rate is divided by the "inch-miles" of sewer pipe that are tributary to the location . The calculated wastewater flow rate is divided by the number of connections to determine a "per connection" rate. o Estimate Inflow rates. . By definition, inflow generates a peak flow condition as a result of a rainfall or runoff event. . During the temporary metering period, 2.05 inches of rain were received on August 27 and 28, 2007. A more significant 1.83 inch rainfall occurred on September 19, 2007 after the temporary meters were removed. The August event will be used for the temporary meter locations and the September event will be used for the MCES meter locations. . The inflow rate is estimated by noting the peak hourly flow rate during the rainfall period and the time of occurrence. . The flow rate for the same time period on a dry day is then subtracted from the peak hourly flow on the rainfall day to separate out the portion of the flow attributable to the rainfall event. This value is the peak hourlv inflow rate. o Calculate an adjusted peak flow rate. . Determine the normal peak hourly wastewater flow on a dry weather day. . Add the peak hourly inflow rate to the peak hour wastewater flow rate to determine a "worst case" peak rate that could occur if the two events were simultaneous. This value is the adiusted peak flow rate. . Calculate a peak flow to average flow ratio for comparison with MCES guidelines. o Calculate inflow rate in gpd per connection and per inch mile of sewer for comparison purposes. The remaining item in the data analysis is the review of the flow graph itself. The flow graph figures provide a graphic comparison of the dry weather flow versus the wet weather peak flow in each meter area. The shape of the graph orthe "flow response" can be an indicator ofthe type of III sources that may be responsible for the clear water flow. The rapid rise and decline as demonstrated in Figure 3 Meter 051 would suggest a direct type connection that contributes flow for a short time during the runoff event and then stops operating after the runoff ceases. A rapid increase and a slow decline demonstrated in Figure 11 Meter 054 suggests a more extended flow contribution from a very long service area (long transport time in the pipes), or a foundation drainl sump pump type connection that requires an extended time after the end of the runoff event for the flow to percolate through the soil to the collector pipe. Page 6 of 12 ~ I C Ol'" -00 ~o <(N ~.<:: 0" >-~ -cu 0::;:: <( ~ C C W J: lJ) a: w I- W :E IL. o >- a: <( :E ::E :) lJ) 10 W ....I m ~ ~ ::;;: a. an <> ::;;: ~ ~ UJ ..J ~ ::;;: '" an <> ::;;: .... an <> ::;;: N an <> ::;;: '" ::;;: . '" ::;;: . ~ an <> ::;;: '" ::;;: N ::;;: ~ an <> ::;;: = o~~ ~~tO _ -= <0 ",,,, '" oCo~ ~ ~ o ~ o;""<o:t r- N - <0 _, ~ 00 Co .... 0)0;""10 ~0)C\1 . "'-_I!l=' r;;;. .......C\Ico....... '" 0;-'0) ~";JN = N ..............co...- r- 0> r- c:c C\I0Co<O .......r--. M ~O> ~ cD OCo~ ~'7cci _ = 10 0'" '" o in 0) <0"'-00 00_;:' ("') ....'" N ON~ 0.......0 <0_ =' C\I 0'" ~ ~OCo~ O~'7r---: 0) = ~ (O<Xl~ (0 ~ Ol .c E ::> Z c o :;:; .. " i;::: ~ VJ cD (I) C1) 0 C) cD "C ..... VJ.c.ai=-E- _"C:~ 610''-, " s:: m .;::; c '-.c. C1) ::s.....1 ~ 0 cD J!! 0 .ce~I~Q.)-.JCD.S l!!~m~~Il!lE~ .!O.c.OOI.S.~_~ ",..0<(00.00. ::;;:01 oroen O>N'" "'-q~ eo 0"'(0 Nr-.... .... 0 0> cici (0 <Xl N o o.......r--.C\1 (")00...- C'\i...-r--....- cici '" <Xl ~ o ...- t- lO r--. ro r--. C\I 0) ~ 0 <0 cici <Xl '" o o (,,)~100 ~C\I<or--. qqf'-:....... OO~ (0 0> r- ...."'''' N ~ r- oON "'N<O "''''N ...-q"l OO~ ....0>'" r- 01 '" 00.... cici~ '" '" .... o C"') 0 0 <0 1O~IOM ~C\lqC\l ciON <: C o _ " ] __J :p -g'f C ro ~ _~:g m -c:OQ.) ~r--.~.Q8iE -oE1O-o ~~-:=E-E~ U)cgili""<l1 PCOloc.Eo lii<(U)_...,-> '-(O>C:(I)~> ~~groOWES 0<(01::;:: ii: '" '" N"'l 00 IOCO(,,)~ ~r--.IO<O .......o.....:cvj an ~ ~ a)M 100'l 010 C"':!...--.::t:~roo ...-..............(00)0) .-: r- N ci {;;~~fB~LO ciciciM~~ ,..; "' ~ ci Q<O'<:ttO ...-q...-"" OOOM , "'''' r- '" cia ....... ...- en a) C\IN..q~ ciciOM 10 (0 <0 co ...-o~...- aooN .... III ~ 00 O'.l 0) C\Iro~,,!~~ .....:O..,...:(t}OCl~ (0 '2:= 25 Ii' I~ I ~_S -0 I:;::;; u -- '", !! Ig Ei~ :E ;:,'" 0 C._ ; r--. 01 E ~ ~ 5 ~ o g ':I~ tf. a:: U .s ~,,:, i5 ~ -o::f a; ~ . I~Il;: ~a. o.u (f) (/) ~ c VJ . ~ ~ Wi J ro .....I~ ..S! .Q .Q I~ CD VJ'U ro-- .:.::0 roa..w<cucc 11l::;;:::;:: D. 0.... o~ "'~ -<i ~ ~ ~ ~ (0 ~ o c:i ~ N N ~ 0> '" r- 01 on '" N q N o o ~ o o o 0> o o ~ 01 o o '" ,..; '" Cii o U Ie ~ "'0 .<:: ::>. (;) e s ~-8 ~(ij Ess ~ ~roro~ VJ~~~ Uicco 0<(<(1- tJ o o ~ ~<O q~ 00 .,. .,. o o c:c 0> "'.... ~'" cicci .,..,. o o <Xl N ~O "'0 0..0 N .,..,. o o '" ,..; '" 0.... '" <Xl ciu:> '" .,..,. I.~ 25 a.t$ a" _c o C 00 u..U I~I~ Ci)Ci) 00 uu ss N ~ ~ o r- ol Ol '" a. o , '" o ~ r- o c0 on '" o C 13 ol '0 a. o e Cii <1> C o (lJ City of Arden Hills March 2008 V. Summary of Analysis Table 5 provides a summaI}' of all the data developed in the previous paragraphs. The MCES II Surcharge program is focused on the" Inflow" portion of the clear water and the highest costs for the City of Arden Hills are associated with flow in this categol}'; however, it is important to consider the infiltration portion as well since both infiltration and inflow result in treatment costs to the community. Using the data included in Table 5, the matrix in Table 6 is developed to prioritize areas for additional work. The various factors were ranked numerically from low to high with the low number reflecting the worst case, so the lowest sum will be the highest priority for additional work. Table 6. - Prtoritization Rankino Matrix Area Infiltration! in-mi PIA Ratio Inflowl in-mi Sum Prioritv Meter MaSl 1 3 2 6 2 Meter 2 3 4 6 13 S Meter 3 4 2 3 9 3 Meter M052 2 3 4 3 .- 9 Meter M054 S 2 5 12 4 Meter MOS9 5 1 1 7 1 ~ ;; ;! -+ g ;! * Note: (urrent data from Meter 1 are not sUItable for companson with other meter sheds. Meter Area M051 is the highest priority for additional work with emphasis on the area between MOS1, Meter 2 and Meter 3. However, the area served by Meter M059 had the highest Inflow Related ran kings and therefore should be considered the highest priority for the III Surcharge reduction efforts. VI. Potential III Sources to consider The flow response demonstrated in Figures 3, 5,7,9,11,13, and 15 provide one indicator ofthe type of III sources that can be anticipated in the service area. The type of sources in turn define the type of further investigative methods that should be considered in the various areas. It is impossible to completely define the sources at this stage of the process but we would anticipate that the sources \lvill be more dearly identified as the investigation effort proceeds. Figure 3 - Meter 051 Flow chart indicates a short duration quick spike in flow with the flow remaining elevated slightly for an extended period of time. This flow pattern suggests a possible mixture of some direct inflow sources, such as catch basins, area drains, low manholes, or roof drains, with some longer acting sources such as sump pump connections, direct footing drainage tile, or leaking service pipes. Figure 5 - Meter M2 flow chart shows an immediate sharp spike with the flow remaining elevated for more than a day following the peak event. This flow pattern suggests primarily longer acting type sources such as sump pumps, direct footing drain tiles, or leaking sewer service pipes. Figure 7 - Meter M3 flow chart shows an immediate sharp spike with vel}' little long term flow impacts. This pattern suggests some direct inflow sources, such as catch basins, area drains, low manholes, or roof drains, with possibly a small number of longer acting sources such as some sump pump connections, direct footing drainage tile, or leaking service pipes. Figure 9 - Meter 052 flow chart indicates a short duration quick spike in flow with the flow remaining elevated slightly for an extended period of time. This flow pattern suggests a possible mixture of some direct inflow sources, such as catch basins, area drains, low manholes, or roof drains, with some longer acting sources such as sump pump connections, direct footing drainage tile, or leaking service pipes. Page 8 of 12 City of Arden Hills March 2008 Figure 11 - Meter 054 flow chart shows an immediate sharp spike with the flow remaining elevated for more than a day following the peak event. This flow pattern suggests primarily longer acting sources such as sump pumps, direct footing drain tiles, or leaking sewer service pipes. Figure 13 - Meter 059 flow chart indicates a short duration quick spike in flow with the flow remaining elevated slightly for an extended period of time. This flow pattern suggests a possible mixture of some direct inflow sources, such as catch basins, area drains, low manholes, or roof drains, with some longer acting sources such as sump pump connections, direct footing drainage tile, or leaking service pipes. The flow spike is significantly higher than the normal flow during the same period which supports the relative severity of the inflow in this selVice area. Figure 15 - Meter Ml flow chart indicates a short duration quick spike in flow with the flow remaining elevated for an extended period of time. While the data are considered questionable, the flow pattern should reflect the flow response in the manhole location. This pattern suggests a possible mixture of some direct inflow sources, such as catch basins, area drains, low manholes, or roof drains, with some longer acting sources such as some sump pump connections, direct footing drainage tile, or leaking selVice pipes. VII. Preliminary Conclusions The peak flow analysis indicates that there is inflow in each of the four primary metersheds while the September 18, 2007 event resulted in a possible "flow exceedence" event at meters M054 and M059 only. The projected peak flow rate at M051 was very near the allowable peak rate, but did not exceed the rate. The work completed to date is the first step identifiying and removing the III in the collection system. Additional investigation will be necessary to further identify sources and complete rehabilitation to reduce the III flow rates. Based on the flow response, it is anticipated that private property type sources including sump pumps, direct foundation drains, and possibly deteriorated sewer selVice connections provide a portion of the inflow in each selVice area; however, in areas M 1 and MOS4 these connections may be the major contributors. In Area M2, the flow response is similar but the selVice area is primarily commercial I industrial so the number of foundation drain type connections is probably limited and this response may be due to a low manhole or area drain that drains slowly after a rainfall event. In areas MOS1, M3, M052, and MOS9, the flow response suggests that there are some direct type connections in addition to some private property sources. The current data are not sufficient to specifically identify sources for the inflow, however, they can be used to plan subsequent data collection and inflow investigation efforts. VIII. Recommendations for next steps The flow data collected during 2007 generally provided some background information and response data for a limited storm event following a very dry summer period. We would recommend conducting additional flow metering at each of the temporary meter sites to try and record the response to a larger (2") rainfall event during more normal groundwater conditions. In addition, all of the lift stations should be calibrated so the running time data can be used to subdivide the flows within the larger MCES meter areas. There are five lift stations in the MOS4 selVice area that may be able to further isolate the suspected private property type sources. Table 7 includes a summary of typical III sources, investigative procedures that are designed to identify these sources, and rehabilitation options typically associated with the particular source. This is not an exhaustive list but can be considered a guide for the next steps in the III identification and rehabilitation process. Page g of 12 City of Arden Hills March 2008 Table 7 - Summary of T voicallll Source, Investiaation Procedures, and Rehabilitation Options Infiltration Potential Source Investigative Procedures Rehabilitation Options or Inflow Inflow Manhole Covers Smoke Test Replace Cover Physical Survey Raise Cover Seal Cover Rim Area Inflow Area Drains Smoke Test Re-route flow to storm sewer or surface discharoe Inflow Roof Drains Building Inspeaion Re-route flow to storm sewer or surface Smoke Test discharge Dve Test Infiltrationl Deteriorated Adjustment Manhole Inspeaion Replace rings and seal Inflow Rings Install sealing product (Chimney seal, Infi- shield) Infiltrationl Sump Pump Connection Basement Inspection He-route discharge out of basement ~o Inflow surface Infiltrationl Direct Foundation Drains TV inspection of service pipe Re-route to sump pump and discharge Inflow outside basement to surface .- Infiltrationl l1'aking Service pipe TV inspection of service pipe Replace service pipe Inflow Install CIPP liner Infiltration Manhole wall seepage Manhole Inspection Grout Injection Replace Manhole Install Manhole liner Infiltration Pipe Joint leakage Televise sewer main Joint Grouting C1PP lining Pipe Replacement In the service areas for meters M 1, M2, and M054, initial investigation efforts should be focused on possible private property type sources. Investigation should include sump pump surveys of individual properties and televising individual service lines during wet conditions. Some communities have had reasonable success televising the service lines from the main sewer using a remote camera. This process is less expensive and significantly less intrusive than attempting to televise services from the basement of a property. In consideration of the potential problems with basement access, we would recommend attempting to televise several service lines in several areas of these service areas to test the procedure and view the results prior to widespread implementation of a program. Since sump pump inspections can be a difficult project and the cost implications can be significant, the progr<lm should be implemented throughout the entire community with priority areas defined by the identified inflow areas. In the service areas for meters M3, M051,M052, and M059, initial investigative efforts should be focused on direct inflow sources, with smoke testing, physical survey of manholes, roof leader inspections, and dye testing as necessary. Manholes located in roadside ditch areas such as those repaired along Hwy 10 can be a significant source of inflow and all manholes located on easements or off paved road areas should be inspected for flooding potential and damaged rings. Sump Pumps are also considered a direct inflow source and they will generate a significant flow spike so a survey in these areas will provide some useful information as well as providing a "complete" inspection. Inflow defects that are identified should be repaired as soon as feasible after identification to reduce the inflow as much and as quickly as possible. This will reduce the MCES treatment charges as well as assist in further evaluation of the system since other defects may become evident when some of the flow is removed. These investigation recommendations are a starting point and problems identified or defects noted may require additional investigation or other unique investigative techniques. The results of each procedure should be reviewed <lnd evaluated to determine the next step in the investigative effort. Pagel00fl2 City of Arden Hills March 2008 IX. Schedule A. 2008 Plan o Install flow meters for peak wet weather period to attempt to capture several rainfall events o Calibrate pumps at each of the collection system lift stations o Evaluate flows from each lift station area and compare to flows at temporary meters and MCES flow meters. o Conduct physical survey of manholes located in "off-road" locations o Complete rehabilitation of any identified manhole inflow sources o Experiment with televising sewer service lines in 10 - 20 locations B. 2009 Plan o Conduct sump pump surveys of 50 % of the sewer service area. o follow up on sewer service line inspection based on experience from 2008 o Evaluate flows throughout system using lift station metering points and MCES Meters o C. 2010 Plan o Conduct sump pump surveys of remaining 50% of the sewer service area o Evaluate flows throughout system using lift station metering points and MCES Meters. o Consider sewer replace programs if defective services are identified. D. 2011 Plan o Complete any remaining rehabilitation projects Page 11 of 12 City of Arden Hills March 2008 Appendix Figures 1 through 15 Page 12 of 12 (j \ /':,~""'-\, -----:J f . I -\ ......,..... r-- , lS 8- . S~e;ti0i1'8 v , r- t T Figure 1 LEGeND; R_Amo""" (3ill.......I\tMM-3 ___1,l.';1 8__1.1<12 ~__M-liS __..._M~ j---,........_M~ ji~- ..._Gouro:1IMo.... .~Mo"" 0-- .~- .~- N-_ m ~ N ~ ~HIU; -,,- if~~1~~:;;~~~~~ -- --- I -,~ FIGURE 2 ESTIMATION OF INFILTRATION I INFLOW Meter Shed IM051 Estimated Residential Equivalent Connections Inch Miles of Sewer pipe (w/o services) I 11~~lin-mi Method 1 - Assume no 1/1 in January Annual January pejk Mo. Average 2004 0.448 0.362 0.540 June 2005 0.432 0.367 0.534 Oct 2006 0.435 0.408 0.579 May 1/1 (mgd) 0.086 0.065 0.027 (MG annual) 31.39 23.73 9.86 64.97 1,543 100,249 33,416 (%) 19.20% 15.05% 6.21% 13.48% Monthly Flow Data (mgd) Calculated GPO per connection 2006 rate $ Total Cost $ Annual $ (3 yr avg) Annual January pejk Mo. Average 2004 496 400 597 2005 478 406 591 2006 481 451 640 Method 2 - Assume early morning low flow is entirely inflitration (clear water) May - September 2007 8/30/2007 Daily Flow Dry Day - Early Morning Flow Net Wastewater 10,000 Igph I 453,000 Igpd 240,000 gpd 213,000 gpd Infiltration rate: (EMFfln mil 2,050 gpdJin mi Wastewater per connection: 236 gpdlconnection Peak Flow 9/20/07 Peak Hour Rate: 20:00 hrs Dry day flow at time INFLOW Inflow per connection 49,861 gph 1.197 mgd 16,568 gph 0.398 mgd 33,293 gph 0.799 mgd 0.690 1.491mgd 3.29 884 gpdlconnection 6,824 gpdlin mi Normal Peak Adjusted Peak Calc. PIA Ratio Inflow per in mile M051 - .__..________.______._ _. __.___.___.__ _____,~_____.____.____..__.__._..__.____ _n_ 1'-1'- 00 1'-00 OC\lC\l --- --- 00>'- C\IC\IC\I --- . . 01'-0> C")C\I.- --- --- --- a:> a:> 0> + t + - 00, ',( - ac- V, ~ - a ,( V- ,... -C' at) a ,( 0 V- :E -6' 00_ (/) - "$' - 00, - .- :J: ',( c:: 00. 0) Q) -,( c: a c- .- 'tJ 'tJ '- V, c: <C <' UJ a ,( I ~ v- ... .C' :J ('I) a ,( 0 C1) I- 0.6- J: ~ '- ;j t 00. I Cl t "$' .- r- a LL ~ 1'..{ 00_ ',( t a c- V, ~ a ,( I- 1'.~ ! a ,( 1'.6- 00_ 'S a 0 0 0 0 0 0 0 1'..{ 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 <0 l!) ~ C") C\I .- Hd~ U! MOI::l FIGURE 4 ESTIMATION OF INFILTRATION I INFLOW Meter Shed 1M2 20,1lin.mi Estimated Residential Equivalent Connections Inch Miles of Sewer pipe (w/o services) Method 1 - NOT APPLICABLE FOR TEMPORARY METERS Method 2 - Assume early morning low flow is entirely inflitration (clear water) May - September 2007 8/23/2007 Daily Flow Dry Day - Early Morning Flow Net Wastewater 73,700 jgpd 28,800 gpd 44,900 gpd 1 ,200 19ph Infiltration rate: (EMF/in mil 1,433 gpd/in mi Wastewater per connection: #DIV/O! gpd/connection Peak Flow 8/28/07 Inflow per in mile 6,400 gph 0.154 mgd 3,950 gph 0.095 mgd 2,450 gph 0.059 mgd 0.100 0.161mgd 2.17 #DIV/O! gpd/connection 2,925 gpd/in mi Peak Hour Rate: 08:55 hrs Dry day flow at time tNFLOW Normal Peak Adjusted Peak Calc. PIA Ratio Inflow per connection M2 N Cl) - .- W U) - - .- :t: c: Cl) "C 10. <( I it) Cl) 10. :::::I C) .- u. "- "- 00 ,,-00 o~~ o ~ ()) C\l~C\l o~~ ~~C\l ~ ~ ~ CXlCXlCXl I I I OO:6~ OO:8~ OO:L OO:~ OO:6~ OO:8~ OO:L Cl c '5 OO:~ c:: w ... ~ 00:61 (l ::i: OO:8~ OO:L OO:~ OO:6~ OO:8~ OO:L OO:~ 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 q o. o~ r-: co to <<i C') N ~ Hd~ U! MOl::! Estimated Residential Equivalent Connections Inch Miles of Sewer pipe (w/o services) 38.9Iin-mi FIGURE 6 ESTIMATION OF INFILTRATION I INFLOW Meter Shed 1M3 Method 1 - NOT APPLICABLE FOR TEMPORARY METERS Method 2 - Assume early morning low flow is entirely inflitration (clear water) May - September 2007 8/23/2007 Daily Flow Dry Day - Early Morning Flow Net Wastewater 133,050 Igpd 51,600 gpd 81 ,450 gpd 2,150 Igph Infiltration rate: (EMF/in mil 1,326 gpd/in mi Wastewater per connection: IDlY 10! gpd/connection Peak Flow 8/28/07 Peak Hour Rate: 03:55 hrs Dry day flow at time INFLOW 11,100 gph 0.266 mgd 2,550 gph 0.061 mgd 8,550 gph 0.205 mgd 0.280 0.491mgd 3.68 IDlY IO! gpd/connection 5,275 gpd/in m i Normal Peak Adjusted Peak Calc. PIA Ratio Inflow per connection Inflow per in mile M3 1'-1'- 00 1'-00 oC\lC\l ~ ~ 0<1"0> C\I~C\I ~ . . 0~1'- ~ ~ C\I ~ ~ ~ rororo I \ \ OO:~Z OO:H 00:8~ 00:6 ('I) 00:9 Q) OO:~ - .- en OO:~Z t/) OO:H - - .- 00:8~ :t: c: 00:6 Cl Q) 00:9 c "C '6 ~ OO:~ c <( W ... OO:~Z :J . 0 r-- OO:L~ :t: Q) 00:8~ ~ ;j 00:6 tn .- 00:9 U. OO:~ OO:~Z OO:H 00:8~ 00:6 00:9 OO:~ 0 0 0 0 0 0 0 0 0 0 0 0 0 0 q 0_ q o~ 0 C\I 0 ro <0 <I" C\i ~ ~ Hd~ U! MOI~ FIGURE 8 ESTIMATION OF INFILTRATION I INFLOW Meter Shed I M052 Estimated Residential Equivalent Connections Inch Miles of Sewer pipe (w/o services) 1121 13.6 in-mi Method 1 - Assume no VI in January Monthly Flow Data (mgd) Annual January peat Mo. Average 2004 0.039 0.030 0.047 June 2005 0.039 0.035 0.043 June 2006 0.038 0.036 0.043 Sep III (mgd) 0.009 0.004 0.002 (MG annual) (%) 3.29 23.08% 1.46 10.26% 0.73 5.26% 5.48 12.87% 1,543 8,448 2,816 Calculated GPD per connection 2006 rate $ T olal Cost $ Annual $ Annual January Peak Mo. Average I 2004 348 268 420 2005 348 313 384 2006 339 321 384 Method 2 - Assume early morning low flow is entirely inflitration (clear water) May - September 2007 8/30/2007 Daily Flow Dry Day - Early Morning Flow Net Wastewater 43,000 Igpd 24,000 gpd t 9,000 gpd 1,000 jgph Infiltration rate: (EMFlin mil 1,765 gpd/in mi Wastewater per connection: 170 gpd/connection Peak Flow 9/20/07 Inflow per connection 4,302 gph 0.103 mgd 1,97t gph 0.047 mgd 2,331 gph 0.056 mgd 0.080 0.141mgd 3.26 500 gpdlconnection 4,114 gpdlin mi Peak Hour Rate: 19:00 hrs Dry day flow at time INFLOW Normal Peak Adjusted Peak Calc. PIA Ratio Inflow per in mile M052 _ _ _____.._____._____________u,___.______~ ___._.. ___.._.._______.__n___.__n --- ------~-. -" -- ---- _._..__._.....__ "__m.____ _ ___~___. --.-.. N IJ) o :!: U) - - .- J: c Q) "C ... <C . 0') Q) ... ;:] en .- u. \ o o o LO t-- t-- 0 0 t-- 0 0 C\I C\I 0 -- -- 0 (j) T""" C\I C\I C\I -- , I 0 t-- (j) c;t) C\I T""" -- -- -- 00 00 (j) + + + 1 00. 1= ..( 1= aC> v. i- ~ \= a .( o.~ ~ a .( v. ~ .~ a v 0.& I-- a v f= v. ..( a 0 r:: V. ... 1- ..( :1 1- a C> 0 ,-- I:: v. ::E: 1- ~ Cl r a .( c != V. "0 ~ 'C' a .( c l- V. UJ 1 F .~ ,- Q V i_ V. 1= ',Q 1- a v E v. '.( f- a 0 ~ o..i [ a C> I r V. i- ~ F a .( 1= V. 'C' 1- a .( i 1 0.<2 ~ a v v. '$) a v 0 0 0 0 0 0 0 0 0 0 o..t 0 0 0 0 0 0 0 0 0 LO 0 LO 0 LO 0 LO 0 LO 0 ~ ~ C') C') N C\I T""" T""" Hd9 U! MOl:! FIGURE 10 ESTIMATION OF INFILTRATION I INFLOW Meter Shed IM054 Estimated Residential Equivalent Connections Inch Miles of Sewer pipe (w/o services) 10791 122.9 in-mi Method 1 - Assume no III in January Monthly Flow Data (mgd) Annual January Peak Mo. Average I 2004 0.198 0.175 0.264 June 2005 0.197 0.172 0.278 Oct 2006 0.183 0.184 0.264 May III (mgd) 0.023 0.025 (MG annual) (%) 8.40 11.62% 9.13 12.69% 0.00% 8.10% 17_52 1,543 27,033 9,011 Calculated GPD per connection 2006 rate $ Total Cost $ Annual $ Annual January Pear Mo. Average 2004 184 162 245 2005 183 159 258 2006 170 171 245 Method 2 - Assume early morning low flow is entirely inflitration (clear water) May - September 2007 8/30/2007 Daily Flow Dry Day - Early Morning Flow I Net Wastewater 181,0001gpd 76,800 gpd 104,200 gpd 3,200 19ph Infiltration rate: (EMFlin mil 625 gpd/in mi Wastewater per connection: 97 gpd/connection Peak Flow 9/20/01 Inflow per connection 23,767 gph 0.570 mgd 7,869 gph 0.189 mgd 15,898 gph 0.382 mgd 0.270 0.65 lmgd 3.59 354 gpd/connection 3,105 gpdlin mi Peak Hour Rate: 20:00 hrs Dry day flow at time INFLOW Normal Peak Adjusted Peak Calc. PIA Ratio Inflow per in mile M054 ""_n~____ ,_ __.__"_________ _,._____ _____o___n -----~- __ _,_____.. __ __,,___,O~_.___ _ _________ 0-' o::t it) o :E UJ - - .- J: c Q) '0 - c:( I ,... ,... Q) - :J en .- u.. ---_..~---_..~-"_..---_.--- .. /"-/"- 00 /,,-00 o~~ Om,.... C\IC\1C\1 or.:.d> C')C\I"'" --- --- --- a:>a:>m + + + I I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 LO 0 LO 0 LO C\I C\I ,.... ,.... Hd~ U! MOI::l ---r I: I- I- a I- v.", i- 1= a c'> , v- 1= ~ a ,{ v. 'C' ~ a ,( v. '6) 1- a v 1- V. 1- '"Q 1 1= a v v. 1- ..( I: a 0 ... V. :::l ; .,{ 0 ,- a c'> 1 \~ v. :I: ~ Cl a ,{ r::: ~ V. .- -C' "C a ,( c: [ v- UJ I' '6) i: a v L V. [ " '"Q I: a v ,. v- L t -.( a 0 I: v- I- -,{ !-. a c'> ~ V. \: "<' a ,{ ~ v- 'C' a ,( ,. v- t- -6) ,- a v l- I v- , ,- "S) a v 0 v- ..( 0 FIGURE 12 ESTIMATION OF INFilTRATION I INFLOW Meter Shed IM059 11491 142.5 In-ml Estimated Residential Equivalent Connections Inch Miles of Sewer pipe (w/o services) Method 1 - Assume no 1/1 in January Monthly Flow Data (mgd) Annual January Peak Mo. Average I 2004 0.317 0.313 0.371 June 2005 0.312 0.310 0.337 Oct 2006 0.286 0.321 0.380 May 1/1 (mgd) 0.004 0.002 (MG annual) (%) 1.46 1.260;'; 0.73 0.64% 0.00% 0.63% 2.19 1,543 3,379 1,126 Calculated GPD per connection 2006 rate $ Total Cost $ Annual $ Annual January pejk Mo. Average 2004 276 272 323 2005 272 270 293 2006 249 279 331 Method 2 - Assume early morning low flow is entirely inflitration (clear water) May - September 2007 8/30/2007 Daily Flow Dry Day - Early Morning Flow Net Wastewater 230,000 Igpd 100,800 gpd 129,200 gpd 4,200 Igph Infiltration rate: (EMF/in mil 707 gpd/in mi Wastewater per connection: 112 gpd/connection Peak Flow 9/20/07 Inflow per connection 57,398 gph 1.378 mgd 10,465 gph 0.251 mgd 46,933 gph 1.126 mgd 0.320 1.45 Imgd 6.30 980 gpd/connection 7,905 gpd/in mi Peak Hour Rate: 20:00 hrs Dry day flow at time INflOW Normal Peak Adjusted Peak Calc. PIA Ratio Inflow per in mile M059 --~----------_.-------- - 1"-1"- 00 1"-00 OC\lC\l --- --- Om,.... C\IC\1C\1 --- , , ol"-m C')C\I"'" --- --- --- a:>a:>m t + + 00. .,( aC> v. a <',{ en v.~ Lt) a ,{ 0 v.6l :E a v UJ ; v.,Q - - ,- a v .- r- J: E v.", c (- a 0 ... Q) ,- v. ~ ,- .,{ '0 L a C> 0 1 - \: V. :I: c:( " <' 1- Cl I ~ a ,{ r::: F v. .- ('l) 'C' "C ,... \: a ,( r::: t v.6l UI Q) - a v :J 1- v.,Q en ~ .- f- a v u.. t V. I .,{ [ a 0 L v.", ( ~ aC> ~ 1-- V. ~ a <,{ 1- , ~ v.~ a ,( S v.6l a v F v.,Q a v 0 0 0 0 0 0 0 0 v..t 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 l"- e!) LO "<t C') C\I ,.... Hd~ U! MOI::l FIGURE 14 ESTIMATION OF INFilTRATION I INFLOW Meter Shed IM1 Estimated Residential Equivalent Connections Inch Miles of Sewer pipe (w/o services) 77.4lin.mi Method 1 - NOT APPLICABLE FOR TEMPORARY METERS Method 2 - Assume early morning low flow is entirely inflitration (clear water) May - September 2007 8/23/2007 Daily Flow Dry Day - Earty Morning Flow Net Wastewater 419,500 ~gpd 73,200 gpd 346,300 gpd 3,050 Igph Infiltration rate: (EMF/in mil 946 gpd/in m i Wastewater per connection: ItDIV/O! gpd/connectioll Peak Flow 8/28/07 Inflow per connection 48,100 gph 1.154 mgd 15,800 gph 0.379 mgd 32,300 gph 0.775 mgd 0.750 1.531mgd 3.65 ItDIV/O! gpd/connection 10,016 gpd/in m i Peak Hour Rate: 08:55 hrs Dry day flow at time INFLOW Norm al Peak Adjusted Peak Calc. PIA Ratio Inflow per in mile M1 1'--1'-- 00 00 I'--C\J~ g~o> C\J~C\J o;..~ .,.... T""" C\J --- --- --- CO CO CO I I I OO:6L OO:8L ,.... OO:L CD - OO:L .- en f/J OO:6L - - .- J: OO:8L s:: CD OO:L Cl "C c: :I.. '0 <( OO:L c w ~ ... . :J It) OO:6L 0 ~ J: ,.... CD OO:8L :I.. ::::J en OO:L .- LL OO:L OO:6L OO:8L OO:L OO:L 0 0 0 0 0 0 0 0 0 0 0 0 0 o. 0 0 0 q 0 0 0 0 0 0 0 <0 l!) '<t (") C\J ~ Hd~ U! MOl:! I" i , i I , ! 1 =~'W i I ! I , , ; i ; I , i I ! 1 I , , i " c Q TI ill ~ " w c E Q ro TI c ill C ~ N W );3 E " ~ ill ill R ill ill ~ ------{z ill ill Q ill ~ " gE; " -'! o c "0 ~ ~ 0 :2: ~ ()) Qj >-.::: "8 ~ ~ ::2: iU c "0 '5 ()) iJ) 8. .f1 Q.u~~Ei5 f5 ~ 0 ~ ~ (j) b () (f) iJ) z I~ I) \ I ; i i I i ! i i i i I i I ,";" o w o >i~ - i:J ~ - fa :E c . e. :2 0.. t; C " c ~ E .2:' !A (5 ~~ I [:' '-'< " ~ ~ ,.,.., IJz i ~~9J -<