2016 UNDERWATER BRIDGE INSPECTION REPORT. 81(ENCHANTED LANE) over CHANNEL. Date of Inspection: Equipment Used: 09/07/2016

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1 2016 UNDERWATER BRIDGE INSPECTION REPORT BRIDGE # 27A34 81(ENCHANTED LANE) over CHANNEL DISTRICT: Metro COUNTY: Hennepin CITY/TOWNSHIP: Shorewood STATE: Minnesota Date of Inspection: Equipment Used: 09/07/2016 Owner: City or Municipal Highway Agency Inspected By: Stuber, Cory Report Written By: Cory Stuber Report Reviewed By: Final Report Date:

2 TABLE OF CONTENTS PAGE NUMBER UNDERWATER SUMMARY 3 UNDERWATER INSPECTION 4 UNDERWATER INSPECTION PROCEDURES 6 STRUCTURE INVENTORY 7 ELEMENTS 8 PICTURES 11 DRAWINGS 14

3 UNDERWATER INSPECTION REPORT SUMMARY The substructure units inspected at Bridge No. 27A34, Piers 1 and 2, were found to be in good condition with no defects of structural significance observed. The channel bottom material consisted primarily of sand infill and large riprap. The channel bottom appeared stable with no significant scour. INSPECTION FINDINGS (A) The channel bottom material consisted of cobble with sand infill with up to 2 inch penetration (B) The timber piles were generally sound and in good condition with negligible deterioration. (C) Riprap, up to 2 feet diameter, protected both banks in the vicinity of the structure. RECOMMENDATIONS (A) Reinspect the submerged substructure units at the normal maximum recommended (NBIS) interval of sixty (60) months. Contractor: Contractor Job Number: Collins Engineers Inc Page 3 of 15

4 UNDERWATER INSPECTION 1. BRIDGE DATA Bridge #: Feature Intersected: Facility Carried: District: County: 27A34 CHANNEL 81(ENCHANTED LANE) Metro Hennepin Bridge Description: The bridge superstructure consists of three spans of multiple timber beams. The superstructure is supported by two timber pile abutments and two timber pile bent piers. The piers are numbered 1 and 2 starting from the west end of the bridge. 2. INSPECTION DATA Professional Engineer/Team Leader: Inspection Diver: Date of Underwater Inspection: Weather Conditions: Underwater Visibility (feet): Waterway Velocity (ft/sec): Garrett Owens P.E. Cory Stuber P.E. 09/07/2016 Cloudy, 75 F 5.0 Negligible 3. SUBSTRUCTURE INSPECTION DATA Substructure(s) Inspected: Piers 1 and 2 General Shape: Piers 1 and 2 each consist of eight timber piles driven to bearing into the channel bottom. Maximum Water Depth at Substructure(s) Inspected (feet): WATERLINE DATUM Water Level Reference: Waterline Elevation (feet): Description: Top of cap at the north end of Pier 1; assumed elevation of feet Approximately 3.7 feet below reference. 5. NBIS CODING INFORMATION (Minnesota specific codes are used for 92B and 113) Item 60: Substructure: Item 61: Channel and Channel Protection: Item 62: Culvert: Item 92B: Underwater Inspection: Code: Code: Code: Code: 8 8 Y 48 09/2016 Page 4 of 15

5 Item 113: Scour Critical Bridge: Code: I Bridge is scour critical because abutment or pier foundation is rated as unstable due to observed scour at bridge site. Yes X No (Mark your selection with an X) 6. STRUCTURAL ELEMENT CONDITION RATING Conditions ELEM # Element Description Quantity Unit CS1 CS2 CS3 CS4 228 Timber Pilings 16 EA Scour 1 EA 1 Page 5 of 15

6 UNDERWATER INSPECTION INSPECTION PROCEDURES The routine underwater inspection of Bridge 27A34 (Enchanted Lane over a channel) was completed on September 7, The underwater inspection was conducted from shore. The inspection was conducted by a team consisting of a PE-Diver with a valid MnDOT Team Leader certification, a backup diver and a dive tender. Due to waterway conditions at the time of inspection, the inspection could be accomplished by wading in accordance with OSHA regulations. Profiles were taken along the upstream and downstream faces of the bridge and around the periphery of substructure units to determine the presence, location and area of scour. The bridge elements inspected consisted of two timber piers. According to the bridge inventory, Piers 1 and 2 were founded on timber pile bents, timber bearing piles and a timber cap, with diagonal timber cross bracing. Inspection procedures followed FHWA guidance and the MnDOT Bridge and Structure Inspection Program Manual with channel bottom probing to search for foundations. The routine underwater inspection frequency is recommended to remain at a maximum of 60 months based on those findings and risk factors. Also, inspection procedures should continue to follow the above approach and standard guidance with 100% Level I and 10% Level II intensity efforts. Page 6 of 15

7 Minnesota Structure Inventory Report Bridge ID: 27A34 81(ENCHANTED over CHANNEL LANE) Date: 01/17/ G E N E R A L + + R O A D W A Y + + I N S P E C T I O N + Agency Br. No. Crew Bridge Match ID (TIS) 0 Userkey 194 District 05 County Hennepin Route Sys 10 - MUN Number 81 Functionally Obsolete City Sect., Twp., Range Latitude ' '' Control Section (TH Only) Status Custodian Owner Main Span Type 7 - Timber Median Width On Bridge Main Span Design Main Span Detail Appr. Span Type Appr. Span Design Appr. Span Detail Skew 0 Culvert Type Barrel Length Cantilever ID MAIN: 3 Main Span Length Structure Length 09 - Slab Span Number of Spans APPR: 0 TOTAL: 20.0 Deck Width (Out-to-Out) 24.0 Deck Material Wear Surf Type Wear Surf Install Year Wear Course/Fill Depth Deck Membrane Deck Rebars Deck Rebars Install Year Structure Area (Out-to-Out) 1248 sq. Roadway Area (Curb-to-Curb) Sidewalk Width 50A. Lt 0.00 Curb Height Shorewood TO SHADY ISLAND Level of Service 1 - MAINLINE N - 23W Roadway Type Lt 8 - Wood or Timber 6 - Bituminous None N - Not Applicable (no deck) + M I S C. Structure Flared Parallel Structure Field Conn. ID Abutment Foundation (Material/Type) Pier Foundation (Material/Type) Historic Status 4 - PILE BENT 2 - TIMBER 4 - PILE BENT Underwater Y 60 Pinned Asbly. Spec. Feat Navigation Control Year Painted 1044 sq. Traffic 50B. Rt Rt Painted Area Primer Type Posted Load B R I D G E D A T A No flare 5 - Not eligible + P A I N T + Bridge Railing 0 - SUBSTANDARD N - No parallel structure GR Transition Appr. Guardrail GR Termini 2 - TIMBER Frac. Critical 0 - Not Required 0 - Not Required Horizontal 0 - Not Required 0.00 Vertical Unsound Paint % Finish Type + B R I D G E 2-2-way traffic Longitude ' '' Reference Point City or Municipal Highway 04 - City or Municipal Highway Roadway Name or Description Township MUN 81 Desc. Loc. BMU Agreement Year Built 1997 MN Year Reconstructed FHWA Year Reconstructed MN Temporary Status Bridge Plan Location Date Opened to Traffic Maint. Area Roadway O/U Key Detour Length 99.0 mi. Lanes Route On Structure On - Off System 0 - OFF Roadway Width Legislative District 33B Vertical Clearance Potential ABC 2 - N/A Max. Vert. Clear. Service On 1 - Highway Appr. Surface Width Service Under 1 - CENTRAL + S T R U C T U R E + HCADT Functional Class If Divided + R D W Y Horizontal Clear. Lateral Clearance ON 2 UNDER ADT 5 - Waterway Bridge Roadway Width YEAR 1988 N - Not Applicable + I N Drainage Area (sq. mi.) + W A T E R W A Y + Waterway Opening (sf.) 200 Pier Protection Posting VEH: Rating Date 07/26/ SUBSTANDARD 1 - MEETS STANDARDS 0 - SUBSTANDARD D E P T H I N S P. + Y/N Freq Date 09/07/ No nav. control on Rail Type Lt 06 Rt 06 A N - N/A B N - N/A C N - N/A sq. ADTT 19 - Urban - Local 20.0 S I G N S + Structurally Deficient Sufficiency Rating 73.6 Routine Inspection Date 08/20/2015 Routine Inspection Frequency 24 Inspector Name + N B I Nav. Clr. () Nav. Vert. Lift Bridge Clear. () MN Scour Code Design Load Operating Rating Stuber, Cory A - Open C O N D I T I O N Deck 8 Unsound Superstructure 8 Deck % Underclearances Waterway Adequacy 9 Approach Alignment 8 0 D I M E N S I O N S + NB-EB % SB-WB Substructure Channel 9 Culvert + N B I Structure Evaluation 8 Deck Geometry 4 Vert. 0.0 Horiz. I - LOW RISK Year C A P A C I T Y R A T I N G S HS 25 (OR GREATER) 2 - HS TRUCK Inventory Rating 2 - HS TRUCK 26.5 N N N SEMI: Overweight Permit Codes 8 N R A T I N G S + A P P R A I S A L R A T I N G S + + S A F E T Y F E A T U R E S + DBL: Page 7 of 15

8 01/18/2017 MINNESOTA BRIDGE INSPECTION REPORT BRIDGE 27A34 81(ENCHANTED LANE) OVER CHANNEL County: City: Township: Hennepin Location: TO SHADY ISLAND Shorewood Route: 10 - MUN 81 Ref. Pt.: Control Section: Section: 30 Township: 117N Range: 23W Maint. Area: Span Type: 7 - Wood or Timber 1 - Slab Local Agency Bridge Nbr.: List: NBI Deck: 8 Super: 8 Sub: 8 Chan: 9 Culv: N Open, Posted, Closed: A - Open MN Scour Code: I - LOW RISK Appraisal Ratings - Approach: 8 Waterway: 9 Required Bridge Signs - Load Posting: 0 - Not Required Traffic: 0 - Not Required Horizntal: 0 - Not Required Vertical: N - Not Applicable Length: 52.0 Deck Width: 24.0 Rdwy. Area/ Pct. Unsnd: 1044 sq. / % Paint Area/ Pct. Unsnd: sq. / % Culvert: N/A Postings: Unofficial Structurally Deficient N Unofficial Functionally Obsolete N Unofficial Sufficiency Rating 73.6 ELEM NBR ELEMENT NAME REPORT TYPE INSP. DATE QUANTITY CS 1 CS 2 CS 3 CS 4 Timber Slab 09/07/ SF Underwater Notes: [2016] Migrator assumed CS SF Wearing Surfaces Underwater 09/07/ SF SF Notes: [08/20/15] Roadway field measures 20'-3" + (2) 11" rub rails, OTO width = 22'-1". OTO bridge field measures 52'-0". Slab Area = 1148 sf. Timber Floor Beam 09/07/ LF Underwater 124 LF Notes: [08/20/15] Element added. 12x6 timber section; (1) stiffener beam in each approach span & (2) stiffener beams in the main span. Same quantity as timber cap, 124 LF, all in Condition State 1 Timber Abutment 09/07/ LF Underwater 102 LF Notes: [2016] Migrator added 40 LF to abutment quantity to account for wingwalls (CS1:40 CS2:0 CS3:0 CS4:0). [08/20/15] Slight quantity change for field measured dimensions, no condition state change. Wingwall notes: Timber Pile 09/07/ EA Underwater 36 EA Notes: [08/20/15] Remove timber column quantity, coded incorrectly. 10 piles at each abutment/ww + 8 piles at each pier, total = 36, all in Condition State 1 Timber Pier Cap 09/07/ LF Underwater Notes: [08/20/15] Slight quantity change for field measured dimensions, no condition state change. 124 LF Timber Bridge Railing 09/07/ LF Underwater Notes: 104 LF Critical Deficiencies or Safety Hazards 09/07/ EA Underwater Notes: NO CRITICAL FINDINGS OBSERVED DURING THE LAST INSPECTION. 1 EA Page 8 of 15

9 BRIDGE 27A34 81(ENCHANTED LANE) OVER CHANNEL ELEM NBR ELEMENT NAME REPORT TYPE INSP. DATE QUANTITY CS 1 CS 2 CS 3 CS 4 Bituminous Approach Roadway 09/07/ EA Underwater Notes: 2 EA Scour 09/07/ EA Underwater Other Bridge Signing 09/07/ EA Underwater 1 EA Notes: [08/20/15] Element added. All object markers accounted for and visible. Vegetation growth at SW corner of abutment growing up around object marker. Slopes & Slope Protection 09/07/ EA Underwater Notes: [08/20/15] No change, channel slopes well protected. 1 EA Guardrail 09/07/ EA Underwater Notes: 1 EA Deck & Approach Drainage 09/07/ EA Underwater Notes: [08/20/15] No change, deck scuppers open, free of debris. 1 EA Miscellaneous Items 09/07/ EA Underwater 1 EA Notes: [08/20/15] Element added. (3) separate conduits on the south side of the bridge. (1) 3" gas line, marked at east end of bridge; (1) 16" conduit (insulated water main?); & (1) 4" conduit (galvanized?). Protected Species 09/07/ EA Underwater Notes: Use this element to track the presence of protected species living on this structure. 1 EA General Notes: 58. Deck NBI: 36A. Brdg Railings NBI: 36B. Transitions NBI: 36C. Appr Guardrail NBI: 36D. Appr Guardrail Terminal NBI: 59. Superstructure NBI: 60. Substructure NBI: 61. Channel NBI: 62. Culvert NBI: [08/20/15] Inspection by WSB. [08/20/15] 40" clearance to bottom of spreader beam in Span 2. [08/20/15] 4' water depth in channel under Span 2. [08/20/15] Removed element 206. [08/20/15] Added element 228. [08/20/15] Added element 415. [08/20/15] Added element 981. [08/20/15] Vegetation growing at SW corner of bridge, nearly obstructing object markers, should be removed. [08/20/15] Timber slab covered by 3.5" bituminous wear course; no change. Measures 2" at the gutter line, 5" at CL bridge. [08/20/15] Change to substandard. [08/20/15] Change to substandard. Approach guardrail ends are turned down. [08/20/15] Timber slab covered by 3.5" bituminous wear course; bottom of timber slab stringers in very good condition in all spans, no change. 40" freeboard to Span 2 spreader beam. Page 9 of 15

10 BRIDGE 27A34 81(ENCHANTED LANE) OVER CHANNEL ELEM NBR ELEMENT NAME REPORT TYPE INSP. DATE QUANTITY CS 1 CS 2 CS 3 CS Waterway Adeq NBI: 72. Appr Roadway Alignment NBI: Cory Stuber Inspector's Signature Reviewer's Signature Page 10 of 15

11 Pictures Photo 1 - South Elevation, Looking North. Photo 2 - North Elevation, Looking Southwest. Page 11 of 15

12 Pictures Photo 3 - Pier 1, Looking East. Photo 4 - Pier 2, Looking East. Page 12 of 15

13 Pictures Photo 5 - West Abutment, Looking West. Photo 6 - East Abutment, Looking East. Page 13 of 15

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