APPENDIX A Geotechnical Investigation Report Municipal Works LANDTEK LIMITED 01110021. r Consulting Engineers 2--- 205 Nebo Road, Unit 3 Phone: 905- 383- 373324,3-/ Hamilton, Ontario Fax: 905- 383 -8433 % - 7 Canada engineering @landteklimited.com L8W 2E1 www.landtekiimited. com t?7 nci'i1Cl1 February 19, 2013 . File: 12290 & 12291 FEB 2 0 2013 ENIGINEERING The City of Niagara Falls g Infrastructure and Asset Manager, Municipal Works City of Niagara Falls 4310 Queen Street Niagara Falls, Ontario L2E 6X5 Dear Mr. Kent Schachowskoj, P. Eng., Re: Geotechnical Investigation Proposed Gabion Wall Rehabilitation Welland River Culvert on Chippawa Parkway, Structure #S053C 263--1,2— 650 m West of Stanley Avenue City of Niagara Falls, Regional Municipality of Niagara, Ontario Geotechnical Investigation Proposed Bridge Replacement (Structure #S1 19B) Miller Road at Usshers Creek, ±240 m East of Sodom Road City of Niagara Falls, Regional Municipality of Niagara, Ontario I am pleased to submit one bound copy of each of our geotechnical investigation reports for the above noted projects. A PDF file of the full signed reports has been previously sent out to you. I trust that the report is satisfactory for your purposes. If you have any questions, please do not hesitate to call me or my associate Mr. Ralph Di Cienzo, P. Eng. Yours very truly, L/.&NIDTEK LIMITED Paul Anderson, P. Eng. P DA/ FOUNDATION INVEST €CATIONS ENVIRONMENTAL SITE ASSESSMENTS AND CLEANUP GROUNDWATER STUDIES R SLOPE STABILITY STUDIES ASPHALT TECHNOLOGY ASPHALT MIX DESIGNS PAVEMENT PERFORMANCE ANALYSIS. CONSTRUCTION MATERIALS TESTING & INSPECTION ANALYSIS OF SOIL CORROSION POTENTIAL PAVEMENT REHABILITATION & TENDER SPECIFICATIONS CONCRETE QUALITY ASSURANCE TESTING ROOF INSPECTIONS INFRASTRUCTURE NEEDS STUDIES FAILURE ANALYSIS AND EXPERT WITNESS SERVICES N AGGREGATE EVALUATION 263- 1-2-- LANOTEK LIMITED Consulting Engineers 205 Nebo Road, Unit 3 Phone: 905 -383 -3733 Hamilton, Ontario Fax: 905 -383 -8433 Canada engineering@landtekdmited. com L8W 2E1 www.landteklimited. com G eotec h n i ca I Investigation Proposed Gabion Wall Rehabilitation Welland River Culvert on Chippawa Parkway, Structure #S053C 650 m West of Stanley Avenue City of Niagara Falls, Regional Municipality of Niagara, Ontario Prepared for: The City of Niagara Falls c/ o ELLIS Engineering Inc. 214 Martindale Road, Suite 201 St. Catharines, Ontario L2S 0132 Project No.: 12290 January 21, 2013 FOUNDATION INVESTIGATIONS ENVIRONMENTAL SITE ASSESSMENTS AND CLEANUP GROUNDWATER STUDIES SLOPE STABILITY STUDIES ASPHALT TECHNOLOGY r ASPHALT MIX DESIGNS PAVEMENT PERFORMANCE ANALYSIS CONSTRUCTION MATERIALS TESTING & INSPECTION ANALYSIS OF SOIL CORROSION POTENTIAL PAVEMENT REHABILITATION & TENDER SPECIFICATIONS CONCRETE QUALITY ASSURANCE TESTING ROOF INSPECTIONS INFRASTRUCTURE NEEDS STUDIES FAILURE ANALYSIS AND EXPERTWITNESS SERVICES AGGREGATE EVALUATION Proposed Gabion Wall Rehabilitation, Welland River Culvert on Chippawa Parkway File: 12290 City of Niagara Falls, Regional Municipality of Niagara, Ontario Page i January, 2013 EXECUTIVE SUMMARY Landtek Limited is pleased to submit the geotechnical investigation report for the proposed rehabilitation structure (## about 650 of the existing gabion retaining walls at the culvert S053C) on Chippawa Parkway ELLIS m west of Stanley Avenue in the City of Niagara Falls, Ontario. The work was authorized by Engineering Inc. on behalf of the City of Niagara Falls on December 7, 2012. A 2011 municipal bridge appraisal report indicates that the gabion baskets are rotating away from the support and settlements in the As roadway with the result that there has been reduced lateral roadway. well, the appraisal report indicated that although the concrete channel of the culvert appeared in good condition there was evidence of erosion and loss of subgrade support under the concrete channel. Boreholes 1 and 2 were drilled on December 19, 2012, each to a depth of 5. 0 m, and at the west and east on site plan, in ends of the culvert respectively. The locations of the boreholes are shown the drawing 1 Appendix C. Photographs of typical site conditions are presented in Appendix D. The ground surface elevations at the borehole locations were surveyed by City of Niagara Falls forces and were provided to Landtek Limited. The elevations refer to the geodetic datum. SITE AND SOIL CONDITIONS The subject site is at the location where an existing tributary watercourse to the Welland River crosses Chippawa Parkway, about 650 m west of Stanley Avenue in Niagara Falls. The ground levels at boreholes 1 and 2 were 175.4 m and 175. 0 m respectively and the water level of the watercourse at the time of the borehole drilling was approximately 4. 4 m below the centreline road grade at the middle of the bridge. soil Warren and younger Geologic map data [ 1 and 2] indicate that the predominant overburden is Lake information pre -Iroquois stratified clay, silt, and sand that overlies shaley dolostone bedrock. The geologic 2] also indicates that the bedrock depth is in the order of 30 m to 35 m. The borehole findings are consistent with the available data and indicate that native layered and fractured overlain with extends to depths of 1. 4 m at silty clay is the predominant native soil, The clay is fill that borehole 1 on the west side of the culvert and 1. 1 m at borehole 2 on the east side. The boreholes were terminated at 5. 0 m and bedrock was not encountered, SPT values in the silty clay range from 14 blows to 41 blows and indicate the stratum ranges from stiff to hard in consistency. Boreholes 1 and 2 were drilled in the westbound and eastbound lanes respectively and there was about 75 mm of bituminous material over granular that had a thickness of 530 mm and 685 mm approximately at the two boreholes. SOIL RETAINING WALL CONSIDERATIONS subgrade support conditions for wall The existing native silty clay soil provides competent retaining construction such that there is no concern for long term differential settlements and base instability under movement which has the retaining wall. The existing gabion basket walls are distorted due to lateral resulted in ground settlement behind the walls and in the roadway. New soil retention systems and/ or and /or soil reinforcement to retaining walls should be constructed and should utilize tie -backs improve type lateral stability. Appropriate soil retaining systems for the project site are considered to be a gravity gabion basket wall with geosynthetic geogrid reinforcement layers, as illustrated in Figure 2, or a geosynthetic reinforced earth type wall system as illustrated in Figure 3. The geosynthetic reinforced earth system with geogrid and geosynthetic materials can include an erosion blanket with topsoil on the face to facilitate vegetation regeneration that results in the remedial soil retention work blending into the overall geometry and natural landscape of the area and a " seamless" wall of natural vegetation growth. Proposed Gabion Wall Rehabilitation, Welland River Culvert on Chippawa Parkway File: 12290 City of Niagara Falls, Regional Municipality of Niagara, Ontario Page ii January, 2013 EXECUTIVE SUMMARY Proprietary design systems such as the Maccaferri systems provide similar capability with natural vegetation regeneration on the face of the gabion wall. Both the gabion basket soil retention system and the geosynthetic reinforced earth system have the advantage that construction can be carried out using conventional construction equipment and methods. The recommendations provided in the previous section and illustrated in Figures 2 and 3 of the report text constitute design and construction concepts and require design analysis based on required finished surface grades, traffic loading impact, and slope inclinations. This work will form part of the preparation of design drawings and specifications with quantities for contract document and tendering purposes. CHANNEL CONDITIONS The concrete channel of the watercourse is supported on the native silty clay and although the concrete appears in sound condition and the flow is not impeded there is evidence that some scour and undermining of the concrete at the inlet and outlet ends ( refer to Photographs 3 and 4 in Appendix D) has occurred over the years. The silty clay is a fine grained soil with greater than 50 % of the soil particles passing the O. O75 mm sieve and the majority of the particles being clay size. Soil erodibility can be assessed using the Wischmeier Nomograph [ 3] and for the soils at the site the soil erodibility factor (K) is less than about 0. 5 which relates to a soil with a moderate resistance to erosion. This is consistent with the evidence that there has not been extensive progressive erosion under the concrete channel. It is recommended that the voids under the concrete channel at the inlet and outlet ends of the culvert be filled with concrete ( 20 MPa nominal 28 day strength) prior to proceeding with any channel improvements see Figure 4 in the report text). It is recommended that the creek bed upstream and downstream of the concrete lined culvert section should be treated with channel protection to dissipate flow and reduce the erosion and scour at the concrete lined channel section. The options for channel protection are rip -rap stone such as OPSS 1004 R -50 material, and rock filled Maccaferri gabion mats or an approved alternate. The gabion mats are designed as a rock -filled cellular basket structures and the cost effectiveness and application of the gabion mats should