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Page 1: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 2: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 3: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 4: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 5: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 6: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 7: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 8: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 9: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 10: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 11: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 12: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 13: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 14: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 15: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 16: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 17: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 18: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 19: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 20: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 21: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 22: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 23: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 24: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 25: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 26: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 27: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 28: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 29: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 30: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 31: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 32: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 33: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 34: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 35: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 36: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 37: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 38: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 39: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 40: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 41: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 42: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 43: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 44: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 45: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 46: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 47: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 48: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

Dam Modification Report Stingy Run Fly Ash Reservoir

Appendix E

Spillway System Design Calculations

E1: Spillway/Energy Dissipater Design for 100-year Event

CHE8273 8 September 4, 2014

Page 49: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

Written by: CJW Date: 04/17/2013 (intro revised

6/18/2014 by ACV)

Reviewed by: MRB Date: 04/26/2013

Client: AEP Project: FAR Closure Project No.: CHE8273 Task No.: 05.4.6

1

APPENDIX E1:

SPILLWAY/ENERGY DISSIPATOR DESIGN FOR 100-YEAR EVENT

PROJECT OVERVIEW

The Stingy Run Fly Ash Reservoir (FAR) is proposed to be closed by draining the reservoir, lowering the existing top of dam, and constructing a cover system. The Final Cover Stormwater Management Plan (Cover Plan), drafted by Geosyntec in 2013, presented the design details of the final cover stormwater management system. The Cover Plan included a hydrologic analysis to determine peak flows at specific locations within the FAR and a hydraulic analysis of the proposed conveyance channels up to the proposed top of dam and spillway. The Cover Plan is included in this Dam Modification Report as Appendix D.

As presented in the Cover Plan, the three main conveyance channels on the proposed cover will converge and the combined flow will be conveyed within a single channel to the modified dam and proposed spillway. The proposed cover conveyance swales consist of a two stage channel design. The low flow channel has been designed to convey the 2 year – 24 hour storm event, which was selected due to the frequency of this potential flow. The second stage was designed to safely convey the 100 year – 24 hour storm event to protect the adjacent cover system. The intent is to minimize flow across the cover cap by concentrating the flows within stabilized channels that will safely convey the 100 year design storm directly to the proposed spillway over the modified dam.

The design for the cover system presented in the Cover Plan extends to the downstream end of the proposed spillway. This calculation package picks up where the Cover Plan left off, detailing the conveyance system downstream of the spillway. Per the hydrologic calculations shown in the Cover Plan, flows in the spillway during the 100 year – 24 hour storm event will reach approximately 1,963 cfs. Conveying these flows from the base of the spillway to Stingy Creek in a safe and efficient manner will require significant energy dissipation. This calculation package focuses on the design of the conveyance system, including energy dissipation measures, immediately downstream of the redesigned dam and spillway, between the base of the dam and Stingy Creek Road.

This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe of dam, channel downstream of energy dissipator) for the 100-year flood event. Subsequent to development of this design, Ohio DNR indicated that the dam spillway component of the system should be designed for the Probable Maximum Flood (PMF). Other parts of the conveyance system described in this chapter (energy dissipator, channel downstream of the energy dissipator) will remain sized for the 100-year event. In addition, the PMF spillway was developed by designing an additional overbank spillway area centered on the 100-year concrete spillway described in this section. Therefore, the design analysis presented in this section remains current for the 100-year event, and this design documentation remains the same as presented in 2013. Appendix E2 describes the hydrologic/hydraulic analysis and design modifications for the PMF spillway.

Page 50: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

Written by: CJW Date: 04/17/2013 (intro revised

6/18/2014 by ACV)

Reviewed by: MRB Date: 04/26/2013

Client: AEP Project: FAR Closure Project No.: CHE8273 Task No.: 05.4.6

2

DESIGN METHODOLOGY

With 100 year peak flows reaching nearly 2,000 cfs in the proposed spillway, and a spillway slope of 12.5%, supercritical flow conditions within the spillway requires the need for energy dissipation measures to be used at the base of the spillway to protect the downstream channel and surrounding area from significant erosion potential. Downstream of this energy dissipator, an elevation drop of approximately 30 feet occurs before flows reach Stingy Creek at Stingy Creek Road. This sharp elevation drop causes the dissipated flows to once again reach supercritical conditions if no tail water condition is assumed, thereby enhancing the complexity of the conveyance system design. As a result of these project conditions, the design of both an efficient energy dissipating system as well as a protected downstream channel needed to be analyzed as one complete system.

The energy dissipation design was carried out in accordance with design guidance from the U.S. Bureau of Reclamation (USBR, 1987) and the U.S. Army Corps of Engineers (USACE, 1990). Based on the spillway flow having a calculated velocity of 54.3 ft/sec and a Froude number of 9.33 immediately upstream of the energy dissipator, a stilling basin was designed in accordance with the Type III Basin characteristics recommended by the USBR (USBR, 1987). See Attachment B for a schematic of this basin design. This type of energy dissipator is known as a stilling basin. Dimensions and design parameters from the final design are described in detail in the Hydraulic Analysis Results section below.

The downstream channel design was first carried out based on topographical conditions and necessary hydraulic capacity. A trapezoidal channel design with 3H:1V side slopes was assumed. Scour protection was analyzed in accordance with the U.S. Department of Transportation Federal Highway Administration’s (FHA) guidance set forth in Hydraulic Engineering Circular No. 11 (FHA, 1989), as well as a more recent article published by Craig Fischenich at the Ecosystem Management & Restoration Research Program (Fischenich, 2001). Both of these specifications were in agreement on suggesting channel stability measures based on flow velocities and scour potential. Details of this design can be found in Hydraulic Analysis Results below. See Attachment C for excerpts from the Hydraulic Engineering Circular No. 11 paper that was used for the selection of rip-rap armament.

HYDRAULIC METHOD OF ANALYSIS

Due to the need to analyze the stilling basin and reinforced channel as a single system, and the many dependent variables involved in the analysis, computer modeling using advanced software was the method of choice to perform the primary hydraulic analysis. This analysis was carried out using the computer program U.S. Army Corps of Engineers (USACE) Hydrologic Engineering Center-River Analysis System V4.1.0 (HEC-RAS). HEC-RAS is a state-of-the-practice software package that allows for the analysis of one-dimensional steady flow through complex open channel systems. The software is capable of analyzing mixed flow regimes as well as situations where the water surface profile is rapidly varied, such as hydraulic jumps. This allows for the software to be efficiently used in the analysis of spillways, energy dissipators, and open channels.

Output from HEC-RAS includes detailed analytical parameters such as depth of flow, flow velocity, hydraulic depth, and whether the flow is sub-critical or super-critical. All of these parameters are essential to the efficient design of the conveyance system downstream of the spillway.

Page 51: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

Written by: CJW Date: 04/17/2013 (intro revised

6/18/2014 by ACV)

Reviewed by: MRB Date: 04/26/2013

Client: AEP Project: FAR Closure Project No.: CHE8273 Task No.: 05.4.6

3

HYDRAULIC ANALYTICAL PARAMETERS

Hydrologic calculations used in this package are detailed in the Cover Plan (Geosyntec Consultants, 2013). The peak 100 year – 24 hour event flow as determined through the hydrologic analysis was 1,963 cfs. Since this storm was used as the basis of design for the proposed conveyance system upstream of the dam, the same design flow was analyzed in this package, conservatively rounded to 2,000 cfs. The 2-year – 24 hour event flow, estimated in the Cover Plan as 450 cfs, was also simulated in order to analyze the system performance under more typical circumstances, and to analyze the design and performance of a downstream culvert at Stingy Creek Road.

As stated above, the stilling basin was designed in accordance with the Type III Basin characteristics recommended by the USBR (USBR, 1987). A summary of the final design parameters is detailed in the Hydraulic Analysis Results section below. The basin was initially assumed to have a rectangular shape with a bottom width equivalent to the total width of the spillway (55 ft). The depth, length, and other design parameters of the basin were adjusted in the model until desirable results were achieved. The sill height at the downstream end of the stilling basin was also adjusted between model runs until an appropriate sill height was reached that created the desired hydraulic jump while keeping the exit elevation reasonably low. This was desirable as it allowed the reinforced channel to have a smaller slope, thus reducing the erosion potential downstream of the stilling basin. The entrance to the stilling basin was designed to be setback a horizontal distance of 20 ft from the base of the dam for added safety. This will require the extension of the spillway at a slope of 8H:1V. From the end of the extended spillway, the transition to the base of the stilling basin was designed with a bottom slope of 1H:1V, with side walls tapering to vertical at the basin. The stilling basin was assumed to be constructed of concrete with a Manning’s roughness coefficient of 0.013 and with a flat bottom.

The downstream reinforced channel following the stilling basin was assumed to be trapezoidal with 3H:1V side slopes. Consistent channel geometry was a target of the design to simplify constructability. The bottom slope of this channel was assumed to be constant from the end of the stilling basin to the downstream culvert at the maintenance drive. The resulting slope is approximately 3.9% and was modeled as such. The channel was assumed to have a gradual curve from the end of the stilling basin to maintenance drive (See Drawing 3 of the Modified Fly Ash Dam Plan Set). The excavated depth of the channel was dependent on the surrounding topography and the depth of flow determined to occur in the channel.

Downstream of the proposed improvements near the property limits, Stingy Creek passes through an existing double box culvert at Stingy Creek Road. The existing double box culvert has the hydraulic capacity to only convey a flow equivalent to the 2 year – 24 hour storm event. The proposed box culvert for the maintenance drive was designed to have a similar capacity to the Stingy Creek Road crossing. The proposed box culvert is designed as a 60 foot, double concrete box with each opening as 5’(H) x 6’(W). Downstream of the culvert, the proposed designed conveyance system will transition to the existing creek.

The details of these structures were determined by performing numerous iterations in HEC-RAS, altering parameters as required until an efficient, feasible design was achieved. The model simulated 3,650 ft of channel, from approximately 1,000 ft upstream of the spillway, where the Type 1 Channel is planned to be constructed, to approximately 1,400 ft beyond the 5’ x 6’ double box culvert, where Stingy Creek flows adjacent to Stingy Creek Road before turning south. The distance from the bottom of the designed spillway to the double box culvert at Stingy Creek Road was approximately 650 ft. This was assumed to be the total length of the conveyance system designed as part of this package.

Page 52: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

Written by: CJW Date: 04/17/2013 (intro revised

6/18/2014 by ACV)

Reviewed by: MRB Date: 04/26/2013

Client: AEP Project: FAR Closure Project No.: CHE8273 Task No.: 05.4.6

4

Input and output summaries from the HEC-RAS model can be found in Table 1 and Table 2. Additionally, Attachment A presents cross-sections and model schematics for both model runs.

HYDRAULIC ANALYSIS RESULTS

A written summary of the results of the hydraulic analysis using HEC-RAS are summarized below. Results are presented based on notable transitions within the conveyance system, beginning at the upstream end of the system and working downstream. Table 2 presents tabulated results from both the 100 year and 2 year storm event model simulations. Other supporting figures, tables, and attachments are noted.

Spillway Extension: The downstream end of the spillway was designed to extend an additional 20 ft away from the dam, continuing at a slope of 8H:1V with the same channel dimensions (25 ft base width; 4H:1V side slopes). This will allow the stilling basin to be placed adequately far from the immediate base of the dam. The spillway extension will end at an elevation of approximately 606.7 ft.

Spillway Transition: From the end of the 8H:1V trapezoidal spillway, the entry transition to the stilling basin will consist of a 1H:1V sloped concrete channel. This channel will be approximately 16.8 ft in length, extending from elevation 606.7 ft to 594.8 ft at a 1H:1V slope. The transition will have a base width of 25 ft at the top to match the spillway and will taper to a width of 55 ft at the bottom. The sidewalls will also match the trapezoidal spillway dimensions at the top, but will transition to vertical walls by the bottom. The top of the sidewalls will be constructed at a steady elevation of 612.9 ft. Chute blocks measuring 1.25 ft high by 1.25 ft wide will be equally spaced across the bottom of the transition channel, where the transition meets the stilling basin. The chute blocks will be spaced equidistantly by 1.25 ft. A total of 22 chute blocks will be constructed along the base of the spillway transition. See Attachment B for a schematic showing a general design of the chute blocks.

Stilling Basin: The stilling basin was designed in accordance with the Type III Basin characteristics recommended by the USBR (USBR, 1987). See Attachment B for a schematic. The concrete basin will be 55 ft wide and will extend away from the dam and spillway with a flat bottom. The bottom will be located at an elevation of 594.8 ft, giving the basin a total depth of approximately 18.1 ft. The sidewalls will be vertical and will extend to an elevation of 612.9 ft. Baffle blocks will be constructed 12.5 ft from the beginning of the stilling basin. The baffle blocks will be 2.0 ft wide and 2.7 ft high with a vertical face. The tops of the blocks will be 0.55 ft long. The downstream side of the blocks will have a 1H:1V sloped face. The blocks will be spaced by 2 ft from edge to edge. A total of 14 blocks will be constructed in place. At the downstream end of the basin, a 2H:1V sloped sill will be constructed. The bottom of the sill will begin 33 ft from the beginning of the stilling basin, and will slope upwards for a vertical height of 5 ft to an elevation of 599.8 ft. The total length of the basin will be 43 ft from the entry transition to the end of the sill. The downstream side of the sill will drop vertically 1 ft to the basin exit transition channel at an elevation of 598.8 ft. A summary of design parameters for the stilling basin is shown in Table 1B.

Basin Exit Transition: From the base of the sill at an elevation of 598.8 ft, the conveyance system will be graded and built to slope downward at a steady slope of approximately 4% until the channel reaches the rebuilt double box culvert at Stingy Creek Road. Exiting the stilling basin, a 50 ft long concrete transition channel will be built to transition the conveyance system from the stilling basin to the reinforced channel. The channel bottom will be 55 ft wide at the base of the stilling basin exit sill and will taper to a 25 ft

Page 53: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

Written by: CJW Date: 04/17/2013 (intro revised

6/18/2014 by ACV)

Reviewed by: MRB Date: 04/26/2013

Client: AEP Project: FAR Closure Project No.: CHE8273 Task No.: 05.4.6

5

bottom width 50 ft downstream, to an elevation of 596.8 ft. The side slopes will also taper over this transition, from vertical side walls at the stilling basin exit sill to 3H:1V sloped walls 50 ft downstream. The depth of the channel will be determined by the grading in the surrounding area, but at no point should the minimum channel depth be less than 10 ft over this transition. A gabion check structure will be built at the end of this 50 ft transition. A summary of design parameters for the basin exit transition is shown in Table 1C.

Gabion Check Structure: A gabion basket check structure (or similarly constructed check structure) will be constructed at the downstream end of the exit transition channel, beginning 50 ft downstream of the sill. The check structure will extend across the entire width of the channel with a 2 ft height above the bottom of the channel until it matches the 3H:1V sloped sidewalls of the channel. The top upstream end of the gabion basket will be constructed to an elevation of 598.8 ft. The gabion basket will be keyed (or notched) into its position by a depth of 1 ft on the bottom, so that the total height of the basket will be 3 ft; it will also be notched into place on the channel sidewalls, extending 6 ft (horizontally) on each side into the channel sidewalls. The total length of the gabion basket check structure will therefore be approximately 37 ft. The check structure will have a top width of 4 ft in the direction of flow. All specifications for the gabion check structure will be in conformance with Supplemental Specification 838 from the Ohio Department of Transportation (Ohio DOT, 2005). See Attachment D. On the downstream side of the check structure, rip-rap will be stacked at a slope of approximately 4H:1V to transition back to the channel floor. Rip-rap shall be AASHTO one ton rip-rap with a D50 of at least 2.85 ft. A summary of design parameters for the gabion check structure is shown in Table 1D.

Reinforced Channel: From the downstream side of the gabion basket check structure, a trapezoidal channel will be constructed at a consistent bed slope to Stingy Creek Road and the newly designed double box culvert. The invert culvert elevation (upstream side) at this point will be approximately 579 ft, based on current topographic data. The channel will have a 25 ft wide base with 3H:1V side slopes. The depth of the channel will be dependent on the surrounding grading, but at no point shall the depth be less than 6 ft. The channel will be reinforced with hard armoring for its entire length to prevent scour and erosion damage due to the steep slope and high Froude number (supercritical flow) produced in the channel during the 100 year event. Rip-rap1 will be used to armor the entire bottom of the channel as well as the sidewalls to a depth of 3 ft. Above a depth of 3 ft, armoring of the channel is not necessary. For the first 25 ft of channel immediately downstream of the check structure, AASHTO one ton rip-rap (D50 = 2.85 ft) will be used for armoring; for the rest of the channel, AASHTO half ton rip-rap (D50 = 2.25 ft) will be used2. A summary of design parameters for the reinforced channel is shown in Table 1E. See Attachment C for relevant excerpts from the FHA Hydraulic Engineering Circular No. 11 (FHA, 1989).

1 A cost analysis has not been conducted to decide on the most cost-effective means of armoring. It should be noted that alternative armoring mechanisms may be selected as long as those mechanisms provide sufficient scour protection in the channel to withstand the velocities and shear stresses calculated in this analysis. Alternatives may include grouted rip-rap, high performance turf reinforcement mat (e.g., Pyramat or Armormax), or articulated concrete block (e.g., Armorflex). 2 Rip-rap size was selected in accordance with the U.S. Department of Transportation FHA Hydraulic Engineering Circular No. 11 (FHA, 1989) based on analyzed shear stresses and velocities in the channel. The D50 sizes presented represent the minimum D50 measurements that may be used; other rip-rap specifications may be used as long as these minimum D50 standards are met.

Page 54: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

Written by: CJW Date: 04/17/2013 (intro revised

6/18/2014 by ACV)

Reviewed by: MRB Date: 04/26/2013

Client: AEP Project: FAR Closure Project No.: CHE8273 Task No.: 05.4.6

6

Double Box Culvert: A concrete double box culvert will be constructed at the first channel undercrossing of Stingy Creek Road. The double box culvert will extend under the entirety of the road, which was estimated to be 60 ft in length in the HEC-RAS model. The culvert was modeled as a 5’(H) x 6’(W) double concrete box. This culvert can sufficiently handle the 2-year storm event. The upstream invert of the culvert was estimated to exist at an elevation of 579 ft; the downstream end at an elevation of 577 ft. It is recognized that these elevations may change based on field surveys and grading constraints.

SUMMARY AND CONCLUSIONS

A conveyance system downstream of the Stingy Run FAR spillway was designed to handle flows from the 100 year – 24 hour storm event. To convey these flows from the base of the spillway to Stingy Creek in a safe and efficient manner, a stilling basin and reinforced channel was designed using HEC-RAS. The stilling basin was designed in accordance with U.S. Bureau of Reclamation standards (USBR, 1987), complete with chute blocks at the entrance, baffle blocks, and a 5 ft exit sill to create a hydraulic jump within the basin. The downstream conveyance channel, which will be unusually steep due to the topography of the site, was designed with hard armoring to protect the channel from scour and erosion. A gabion check structure was also included in the design to slow velocities out of the stilling basin. Additionally, a double reinforced concrete box culvert was designed at the first creek crossing of Stingy Creek Road to effectively convey the 2 year – 24 hour storm event under the road.

REFERENCES

Fischenich, Craig. “Stability Thresholds for Stream Restoration Materials,” EMRRP Technical Notes Collection (ERDC TN-EMRRP-SR-29), U.S. Army Engineer Research and Development Center, Vicksburg, MS. May 2001.

Geosyntec Consultants. “Final_Cover_Stormwater_3-18-13.pdf”. March 18, 2013.

State of Ohio Department of Transportation (Ohio DOT). “Supplemental Specification 838 – Gabions”, April 15, 2005.

United States Army Corps of Engineers (USACE), “Hydraulic Design of Spillways, Engineer Manual 1110-2-1603”, Jan 16, 1990.

USACE, “Hydrologic Engineering Center- River Analysis System”, Version 4.1.0. Davis, CA.

United States Department of the Interior, Bureau of Reclamation (USBR), “Design of Small Dams”, 3rd ed., Denver, CO, 1987.

United States Department of Transportation, Federal Highway Administration (FHA), “Design of Riprap Revetment”, Hydraulic Engineering Circular No. 11, Publication No. FHWA-IP-89-016. McLean, VA, Mar 1989.

Page 55: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

Written by: CJW Date: 04/17/2013

Reviewed by: MRB Date: 04/26/2013

Client: AEP Project: FAR Closure Project No.: CHE8273 Task No.: 05.4.6

G:\CWP\CHE8273 - Stingy Run FAR Closure\5.0 Technical File\5.4 Engineering Work File\5.4.04 Final Design and PTI\5.4.6 Task 7 Dam Design\Calc Package\Draft_Dissipator Design_Narrative_04172013.docx

TABLES AND ATTACHMENTS

Table Table 1A – Model Inputs/Results from Previous Sources and Studies Table 1B – Model Inputs/Results for Stilling Basin Table 1C – Model Inputs/Results for Stilling Basin Exit Transition Table 1D – Model Inputs/Results for Gabion Check Structure Table 1E – Model Inputs/Results for Reinforced Channel Table 2A – Summary of HEC-RAS Output for 100-yr Storm Table 2B – Summary of HEC-RAS Output for 2-yr Storm

Attachments A – HEC-RAS Outputs and Cross Sections for 2-yr and 100-yr Storms B – Stilling Basin Type III Design Schematic, USBR, 1987 C – Excerpts from HEC-11 Rip-Rap Sizing Guidance D – Gabion Basket Specification, Ohio DOT

Page 56: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

Written by: CJW Date: 04/17/2013

Reviewed by: MRB Date: 04/26/2013

Client: AEP Project: FAR Closure Project No.: CHE8273 Task No.: 05.4.6

G:\CWP\CHE8273 - Stingy Run FAR Closure\5.0 Technical File\5.4 Engineering Work File\5.4.04 Final Design and PTI\5.4.6 Task 7 Dam Design\Calc Package\Draft_Dissipator Design_Narrative_04172013.docx

TABLES

Page 57: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

Table 1A

JOB CHE8273-FAR Closure1420 Kensington Road, Suite 103 SHEET NO. OFOak Brook, IL Scott Mansell DATE 4/9/2013TELEPHONE (630) 203 3340 Chris Wessel DATE 4/9/2013FAX (630) 203 3341 Stilling Basin and Conveyance Channel Sizing Summary

Inputs from Previous Sources and Analyses

Value Units

350 ft

630 ft

Various -

577.07 ft

Various -

Various -

0.045 -

0.048 -0.025 -0.035 -0.013 -

2000 cfs

1.23 ft

54.33 ft/sec

9.33 -Froude number in spillway

Scaled off of Figure 2 of downstream analysisScaled off of Figure 2 of downstream analysis

Length, exit slope, n of downstream channel

Manning's n (Riprap d50=2.25')

Manning's n (Riprap d50=2.85')

From spreadsheet used for sizing spillway and checked by calculation

CALCULATED BYCHECKED BY

DESCRIPTION

From SWMM model for natural areaFrom cover swale designFrom cover swale designFrom Cover swale design spreadsheet and given by Matt Bardol

From spreadsheet used for sizing spillway

From spreadsheet used for sizing spillway

Taken from Figure 3 and 4 of downstream analysis and estimated from topography where necessaryTaken from SWMM analysis of downstream analysis

Source

Flow Rate from spillway

From HEC-11 equation 20 n=0.0395*D^0.167

Velocity in spillway

Depth of flow in spillway

Inputs taken from previous sourcesDistance between spillway begin and edge of damDistance between edge of dam and tie in to natural channel

Elevation/slopes/lengths/cross sections of upstream channels and spillway

Sump elevation at tie in to natural channel

Manning's n (Earthen)Manning's n (Turf protection grass)

X-sections of natural channel

From HEC-11 equation 20 n=0.0395*D^0.167

Manning's n (Concrete)

Figure 8273-126 (Details of Dam Configuration) and 8273-123 (Details-Cover System)Taken from Figure 3 of downstream analysis

Page 58: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

Table 1B

JOB CHE8273-FAR Closure1420 Kensington Road, Suite 103 SHEET NO. OFOak Brook, IL CALCULATED BY Scott Mansell DATE 4/9/2013TELEPHONE (630) 203 3340 CHECKED BY Chris Wessel DATE 4/9/2013FAX (630) 203 3341 Stilling Basin and Conveyance Channel Sizing Summary

Stilling Basin Design

Value Units60 ft/sec

20 ft

1:1 H:V

12 ft

55 ft15.6 ft

43 ft

1.25 ft

12.5 ft2.7 ft2 ft

0.5 ft2.7 ft5 ft

1 ft

5 ft

2:1 H:V

DESCRIPTION

Notes:Stilling Basin Material: concreteStilling basin side walls are verticalUsing Type III stilling basin design see figure, From USBR, 1987

Based on riprap d50=2', USACE energy dissipator manual recommends 0.25=0.5 of d100. Assume d100 is about 3', so 1' is between 0.25'-0.5'

USACE energy dissipator manual recommends minimum of 5' flare width

USBR, 1987

From diagram (0.8*d2)From chart in Fig 9-41 (h3/d1=2.2)From diagram (0.75*h3)From diagram (0.2*h3)From diagram 1:1

SourceUSBR, 1987

Set design parameter

USBR, 1987

Design parameter

Design parameter

Sill height (h4)

Elevation drop to channel

Width of basin = Width of SpillwayDepth of hydraulic jump (and depth of stilling basin), d2

Length of basin, L

Analyzed Parameter

d2=d1*0.5*((1+8*Fr^2)^0.5-1)Read from chart in Fig 9-41 (L/d2=2.75, d2=15.6)

From diagram (d1)Chute block height and width, and space between chute blocks

Distance to row of baffles

Flare width after basin

End sill slope

Baffle height (h3)Baffle width and space between bafflesBaffle top lengthBaffle length

Stilling Basin DesignMax allowable velocity

Horizontal offset from bottom of spillway to transition to stilling basin. Continue spillway slope of 12.5%

Slope of transition from spillway to stilling basinElevation drop from bottom of extended spillway to bottom of basin

Page 59: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

Table 1C

JOB CHE8273-FAR Closure1420 Kensington Road, Suite 103 SHEET NO. OFOak Brook, IL CALCULATED BY Scott Mansell DATE 4/9/2013TELEPHONE (630) 203 3340 CHECKED BY Chris Wessel DATE 4/9/2013FAX (630) 203 3341 DESCRIPTION Stilling Basin and Conveyance Channel Sizing Summary

Stilling Basin Exit Transition

Value5

506555

25

3:1Trapezoidal

Concrete

Stilling Basin Exit Transition Unitsftft

Flare width after basin, each sideTransition apron length

This area gradually and continuously transitions to a 25ft bottom width trapezoidal channel with 3:1 side slopes at the downstream check structure.

Note:

ftft

ft

H:VTransition Apron ShapeTransition apron material

Transition apron top width at sillTransition apron bottom width at sillTransition apron bottom width at gabion check structure (downstream end)Side slopes at downstream end

Page 60: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

Table 1D

JOB CHE8273-FAR Closure1420 Kensington Road, Suite 103 SHEET NO. OFOak Brook, IL CALCULATED BY Scott Mansell DATE 4/9/2013TELEPHONE (630) 203 3340 CHECKED BY Chris Wessel DATE 4/9/2013FAX (630) 203 3341 Stilling Basin and Conveyance Channel Sizing Summary

Gabion Check Structure

Value24

DESCRIPTION

ft

Gabion basket check structure placed at end of exit transition, in natural channel. Could be other material if desirable.Extends across width of channel; keyed in 1 ft to natural channel

Notes:

Gabion Check StructureGabion basket height above channel bottomGabion basket top width

Unitsft

Gabion basket must meet specifications of Ohio DOT Supplemental Specification 838 (April 15, 2005)

Page 61: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

Table 1E

JOB CHE8273-FAR Closure1420 Kensington Road, Suite 103 SHEET NO. OFOak Brook, IL CALCULATED BY Scott Mansell DATE 4/9/2013TELEPHONE (630) 203 3340 CHECKED BY Chris Wessel DATE 4/9/2013FAX (630) 203 3341 DESCRIPTION Stilling Basin and Conveyance Channel Sizing Summary

Reinforced Channel

Value Units25 ft3:1 H:V

15.8 ft/sec3.1 ft

12.1 lb/sq ft0.1 -

12.5 lb/sq ft

15.8 lb/sq ft

2.25 ft2.85 ft

Riprap provides higher roughness than concrete to help with velocity, and size is set to protect against scour

From HEC-11 table 3 (AASHTO gradations)

Trapezoidal channel from check structure to culvert, at gradual, constant slope and gradual curve, as necessary to match downstream conditions

Max allowable shear stress based on Shield's equation for 2.25' d50 (1/2 ton)Max allowable shear stress based on Shield's equation for 2.85' d50 (1 ton)Half ton riprap d50

Notes:

One ton riprap d50

Shield's equation constant, tc*

Max hydrualic depth in channel after gabionMax shear stress in channel after gabion

HEC-RAS Output

From Fischenrich, 2001

Shield's equation

Shield's equation

From HEC-11 table 3 (AASHTO gradations)

HEC-RAS Output

Riprap Exit Channel Design SourceDesign ParameterAssumedHEC-RAS Output

Channel bottom widthChannel side slopeMax velocity in channel after gabion

Page 62: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

Table 2A

JOB CHE8273-FAR Closure1420 Kensington Road, Suite 103 SHEET NO. OFOak Brook, IL CALCULATED BY Scott Mansell DATE 4/9/2013TELEPHONE (630) 203 3340 CHECKED BY Chris Wessel DATE 4/9/2013FAX (630) 203 3341 SCALE

DESCRIPTION HEC-RAS Outputs, 100-yr FlowStation Description River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Hydr Depth Flow Area Top Width Froude # Chl Mannings Chnl Mannings Banks Shear

(cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (ft) (sq ft) (ft) (lb/sq ft)Begin Type I Channel 2230 100 year 2000 671.6 677.47 677.24 678.71 0.010003 9.24 2.81 235.35 83.81 0.81 0.04 0.035 2.45Transition Channel 1230 100 year 2000 661.6 667.24 667.24 668.69 0.012515 9.94 2.7 216.77 80.19 0.9 0.04 0.035 2.89Transition Spillway 1170 100 year 2000 661 665.14 665.27 666.79 0.001508 10.7 2.76 206.19 74.66 0.97 0.013 0.013 0.35

Transition 1030 100 year 2000 658.2 662.33 662.38 663.8 0.001895 9.73 2.76 205.64 74.57 1.03 0.013 0.013 0.32Spillway + 20' 980 100 year 2000 652.9 655.43 657.35 663.29 0.016036 22.5 1.96 88.89 45.25 2.83 0.013 0.013 1.94

100' Down Spillway 881.532* 100 year 2000 640.59 642.43 645.04 659.92 0.050967 33.56 1.5 59.6 39.73 4.83 0.013 0.013 4.72200' Down Spillway 780.080* 100 year 2000 627.91 629.54 632.36 653.09 0.07891 38.95 1.35 51.35 38.03 5.91 0.013 0.013 6.58300' Down Spillway 681.613* 100 year 2000 615.6 617.13 620.05 644.35 0.097658 41.86 1.28 47.77 37.27 6.52 0.013 0.013 7.74

Begin Transition to Stilling Basin 610 100 year 2000 606.65 608.15 611.1 637.03 0.106653 43.13 1.25 46.37 36.97 6.79 0.013 0.013 8.27Front of Chute Block 599.38 100 year 2000 596.03 596.77 599.47 634.68 0.291177 49.41 0.74 40.48 54.98 10.15 0.013 0.013 13.03Back of Chute Block 598.14 100 year 2000 594.8 605.68 605.86 0.000055 3.34 10.88 598.35 54.99 0.18 0.013 0.013 0.03

Stilling Basin 590.652* 100 year 2000 594.8 605.68 605.86 0.000055 3.34 10.88 598.35 54.99 0.18 0.013 0.013 0.03Baffles 585.66 100 year 2000 594.8 605.68 605.86 0.000055 3.34 10.88 598.35 54.99 0.18 0.013 0.013 0.03

Top of Baffles 585.65 100 year 2000 594.8 605.6 605.82 0.000205 3.82 9.52 523.47 54.99 0.22 0.013 0.013 0.05Stilling Basin 585.15 100 year 2000 594.8 605.6 605.82 0.000205 3.82 9.52 523.47 54.99 0.22 0.013 0.013 0.05End Baffles 582.444 100 year 2000 594.8 605.61 605.78 0.000056 3.37 10.81 594.21 54.99 0.18 0.013 0.013 0.03

Stilling Basin 575.070* 100 year 2000 594.8 605.61 605.78 0.000056 3.37 10.81 594.21 54.99 0.18 0.013 0.013 0.03Stilling Basin 570.647* 100 year 2000 594.8 605.61 605.78 0.000056 3.37 10.81 594.21 54.99 0.18 0.013 0.013 0.03

Front Edge of Sill 565.24 100 year 2000 594.8 605.61 605.78 0.000056 3.37 10.81 594.21 54.99 0.18 0.013 0.013 0.03Sill 560.74* 100 year 2000 597.05 605.44 605.74 0.00012 4.33 8.39 461.59 54.99 0.26 0.013 0.013 0.05

End Sill, Begin Conrete Channel 555.23 100 year 2000 598.8 604.67 605.22 0.000315 5.92 5.62 337.76 60.06 0.44 0.013 0.013 0.130' Down Concrete Channel 525.23* 100 year 2000 597.63 604.69 605.2 0.000271 5.73 5.64 348.93 61.89 0.43 0.013 0.013 0.09

End Concrete Channel, Gabion 505.23 100 year 2000 596.85 604.75 605.17 0.000234 5.2 5.31 384.57 72.4 0.4 0.013 0.013 0.07Top of Gabion 505.22 100 year 2000 598.85 602.88 602.86 604.47 0.022978 10.11 3.23 197.74 61.18 0.99 0.048 0.048 4.54

Gabion 503.22* 100 year 2000 598.77 602.81 602.78 604.39 0.022823 10.09 3.24 198.2 61.23 0.99 0.048 0.048 4.52End Gabion 501.22 100 year 2000 598.69 602.67 602.68 604.31 0.024096 10.28 3.2 194.52 60.86 1.01 0.048 0.048 4.71

Bottom of Gabion 501.21 100 year 2000 596.69 600.2 601.47 604.19 0.073436 16.03 2.71 124.74 46.07 1.72 0.048 0.048 12.112' Down Exit Channel 499.210* 100 year 2000 596.61 600.15 601.39 604.05 0.070974 15.84 2.73 126.24 46.27 1.69 0.048 0.048 11.84' Down Exit Channel 497.211* 100 year 2000 596.53 600.1 601.31 603.91 0.068688 15.66 2.75 127.7 46.45 1.66 0.048 0.048 11.56' Down Exit Channel 495.212* 100 year 2000 596.45 600.05 601.24 603.78 0.066555 15.49 2.77 129.12 46.64 1.64 0.048 0.048 11.228' Down Exit Channel 493.213* 100 year 2000 596.38 600.02 601.17 603.65 0.064208 15.29 2.79 130.77 46.85 1.61 0.048 0.048 10.91

10' Down Exit Channel 490.214* 100 year 2000 596.26 599.94 601.05 603.47 0.061507 15.07 2.82 132.76 47.1 1.58 0.048 0.048 10.5515' Down Exit Channel 485.216* 100 year 2000 596.06 599.81 600.85 603.17 0.05759 14.72 2.86 135.87 47.5 1.53 0.048 0.048 10.0320' Down Exit Channel 480.218* 100 year 2000 595.87 599.68 600.66 602.9 0.053943 14.38 2.9 139.04 47.9 1.49 0.048 0.048 9.5370' Down Exit Channel 430.295* 100 year 2000 593.92 597.84 598.71 600.83 0.042804 13.87 2.97 144.15 48.53 1.42 0.045 0.045 7.73

120' Down Exit Channel 380.387* 100 year 2000 591.96 595.93 596.75 598.83 0.040998 13.66 3 146.36 48.81 1.39 0.045 0.045 7.48170' Down Exit Channel 330.480* 100 year 2000 590.01 594.02 594.8 596.84 0.039423 13.48 3.03 148.41 49.06 1.37 0.045 0.045 7.25220' Down Exit Channel 280.572* 100 year 2000 588.06 592.13 592.85 594.84 0.037256 13.21 3.06 151.4 49.42 1.33 0.045 0.045 6.94270' Down Exit Channel 230.665* 100 year 2000 586.11 590.29 590.9 592.81 0.033588 12.73 3.13 157.07 50.11 1.27 0.045 0.045 6.4320' Down Exit Channel 180.757* 100 year 2000 584.16 588.33 588.95 590.87 0.034011 12.79 3.13 156.37 50.02 1.27 0.045 0.045 6.46370' Down Exit Channel 130.85* 100 year 2000 582.21 586.39 587 588.91 0.033758 12.76 3.13 156.79 50.07 1.27 0.045 0.045 6.43420' Down Exit Channel 80.9420* 100 year 2000 580.26 586.68 587.45 0.006424 7.03 4.47 284.35 63.55 0.59 0.045 0.045 1.74

Within Transition 30.26* 100 year 2000 578.22 586.67 587.24 0.00239 6.05 4.42 339.27 76.68 0.45 0.037 0.037 0.81Within Transition 10.52* 100 year 2000 577.39 586.38 587.16 0.001901 7.35 3.93 307.92 78.36 0.53 0.028 0.028 0.67Within Transition 5.82* 100 year 2000 577.19 586.32 587.14 0.001797 7.7 3.85 302.9 78.76 0.55 0.026 0.026 0.64

Begin Natural Channel 3 100 year 2000 577.07 586.29 585.38 587.13 0.00174 7.88 3.82 301.44 79 0.56 0.025 0.025 0.61Xsec 2 in Natural Channel 2 100 year 2000 576.17 584.49 584.47 586.4 0.003842 12.14 4 200.16 50 0.85 0.025 0.025 1.43Xsec 1 in Natural Channel 1 100 year 2000 573.02 580.49 580.23 581.9 0.00477 9.71 3.57 214.35 59.99 0.87 0.025 0.025 1.08

Outlet 0 100 year 2000 569.87 575.55 575.55 577.35 0.005045 11.63 3.69 194.98 52.8 0.94 0.025 0.025 1.44

Page 63: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

Table 2B

JOB CHE8273-FAR Closure1420 Kensington Road, Suite 103 SHEET NO. OFOak Brook, IL CALCULATED BY Scott Mansell DATE 4/9/2013TELEPHONE (630) 203 3340 CHECKED BY Chris Wessel DATE 4/9/2013FAX (630) 203 3341 SCALE

DESCRIPTION HEC-RAS Outputs, 2-yr FlowRiver River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Hydr Depth Flow Area Top Width Froude # Chl Mann Chnl Mann Banks Shear

(cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (ft) (sq ft) (ft) (lb/sq ft)Begin Type I Channel 2230 2 year 450 671.6 674.87 674.37 675.42 0.010003 5.98 2.08 75.31 36.13 0.73 0.04 0.04 1.27Transition Channel 1230 2 year 450 661.6 664.37 664.37 665.29 0.019974 7.71 1.82 58.4 32.16 1.01 0.04 0.04 2.22Transition Spillway 1170 2 year 450 661 662.69 662.83 663.58 0.003073 7.59 1.31 59.32 45.26 1.16 0.013 0.013 0.25

Transition 1030 2 year 450 658.2 659.96 660.04 660.76 0.002662 7.2 1.36 62.54 46.11 1.09 0.013 0.013 0.22Spillway + 20' 980 2 year 450 652.9 653.73 654.83 659.48 0.042748 19.25 0.74 23.38 31.61 3.94 0.013 0.013 1.96

100' Down Spillway 881.532* 2 year 450 640.59 641.22 642.52 651.52 0.105409 25.75 0.58 17.48 30.08 5.95 0.013 0.013 3.8200' Down Spillway 780.080* 2 year 450 627.91 628.52 629.84 639.79 0.121437 26.94 0.56 16.7 29.87 6.35 0.013 0.013 4.22300' Down Spillway 681.613* 2 year 450 615.6 616.2 617.53 627.68 0.124857 27.18 0.55 16.55 29.83 6.43 0.013 0.013 4.3

Begin Transition to Stilling Basin 610 2 year 450 606.65 607.25 608.58 618.78 0.125764 27.25 0.55 16.52 29.82 6.45 0.013 0.013 4.33Front of Chute Block 599.38 2 year 450 596.03 601.93 601.96 0.000018 1.39 5.9 324.45 54.99 0.1 0.013 0.013 0.01Back of Chute Block 598.14 2 year 450 594.8 601.94 601.96 0.00001 1.15 7.14 392.45 54.99 0.08 0.013 0.013 0

Stilling Basin 590.652* 2 year 450 594.8 601.94 601.96 0.00001 1.15 7.14 392.45 54.99 0.08 0.013 0.013 0Baffles 585.66 2 year 450 594.8 601.94 601.96 0.00001 1.15 7.14 392.45 54.99 0.08 0.013 0.013 0

Top of Baffles 585.65 2 year 450 594.8 601.92 601.95 0.000049 1.4 5.84 321.37 54.99 0.1 0.013 0.013 0.01Stilling Basin 585.15 2 year 450 594.8 601.92 601.95 0.000049 1.4 5.84 321.37 54.99 0.1 0.013 0.013 0.01End Baffles 582.444 2 year 450 594.8 601.92 601.94 0.00001 1.15 7.12 391.67 54.99 0.08 0.013 0.013 0

Stilling Basin 575.070* 2 year 450 594.8 601.92 601.94 0.00001 1.15 7.12 391.67 54.99 0.08 0.013 0.013 0Stilling Basin 570.647* 2 year 450 594.8 601.92 601.94 0.00001 1.15 7.12 391.67 54.99 0.08 0.013 0.013 0

Front Edge of Sill 565.24 2 year 450 594.8 601.92 601.94 0.00001 1.15 7.12 391.67 54.99 0.08 0.013 0.013 0Sill 560.74* 2 year 450 597.05 601.89 601.93 0.000033 1.69 4.84 266.12 54.99 0.14 0.013 0.013 0.01

End Sill, Begin Conrete Channel 555.23 2 year 450 598.8 601.39 601.54 0.00023 3.1 2.54 145.14 57.23 0.34 0.013 0.013 0.0330' Down Concrete Channel 525.23* 2 year 450 597.63 601.41 601.52 0.000123 2.73 3.28 164.85 50.32 0.27 0.013 0.013 0.02

End Concrete Channel, Gabion 505.23 2 year 450 596.85 601.41 601.52 0.000102 2.55 3.37 176.64 52.4 0.24 0.013 0.013 0.02Top of Gabion 505.22 2 year 450 598.85 600.45 600.43 601.15 0.029748 6.74 1.43 66.79 46.59 0.99 0.048 0.048 2.63

Gabion 503.22* 2 year 450 598.77 600.36 600.35 601.07 0.029971 6.75 1.43 66.62 46.57 1 0.048 0.048 2.65End Gabion 501.22 2 year 450 598.69 600.27 600.27 600.99 0.030702 6.81 1.42 66.1 46.5 1.01 0.048 0.048 2.69

Bottom of Gabion 501.21 2 year 450 596.69 597.82 598.67 600.87 0.205717 14.02 1.01 32.09 31.78 2.46 0.048 0.048 12.822' Down Exit Channel 499.210* 2 year 450 596.61 597.81 598.59 600.48 0.167867 13.12 1.07 34.29 32.2 2.24 0.048 0.048 11.034' Down Exit Channel 497.211* 2 year 450 596.53 597.8 598.51 600.16 0.139226 12.34 1.12 36.46 32.6 2.06 0.048 0.048 9.66' Down Exit Channel 495.212* 2 year 450 596.45 597.78 598.43 599.9 0.11843 11.7 1.17 38.45 32.96 1.91 0.048 0.048 8.518' Down Exit Channel 493.213* 2 year 450 596.38 597.77 598.36 599.68 0.100933 11.1 1.22 40.53 33.34 1.77 0.048 0.048 7.56

10' Down Exit Channel 490.214* 2 year 450 596.26 597.72 598.24 599.42 0.08454 10.47 1.27 42.98 33.78 1.64 0.048 0.048 6.6215' Down Exit Channel 485.216* 2 year 450 596.06 597.63 598.04 599.07 0.065451 9.62 1.36 46.79 34.45 1.45 0.048 0.048 5.4720' Down Exit Channel 480.218* 2 year 450 595.87 597.54 597.85 598.79 0.052764 8.95 1.43 50.27 35.05 1.32 0.048 0.048 4.65

400' Down Exit Channel 111.740* 2 year 450 581.46 584.97 585.17 0.003282 3.61 2.7 124.55 46.05 0.39 0.045 0.045 0.54Just Before Culvert 50 2 year 450 579.05 584.73 581.74 585.03 0.001758 4.4 5.68 102.16 59.07 0.33 0.045 0.045 0.62

Begin Culvert 49.99 CulvertEnd Culvert 3.1 2 year 450 577.07 581.95 579.53 582.26 0.000693 4.5 4.88 99.98 54.27 0.36 0.025 0.025 0.21

Begin Natural Channel 2.95449* 2 year 450 576.95 582.08 582.17 0.000297 2.37 3.63 189.76 52.22 0.22 0.025 0.025 0.07Xsec 2 in Natural Channel 2 2 year 450 576.17 580.69 580.61 581.83 0.006409 8.6 2.27 53.21 23.43 0.94 0.025 0.025 0.97Xsec 1 in Natural Channel 1 2 year 450 573.02 577.6 577.6 578.51 0.008132 7.64 1.81 58.87 32.61 1 0.025 0.025 0.86

Outlet 0 2 year 450 569.87 572.86 572.84 573.75 0.006301 7.69 1.65 61.58 37.25 0.92 0.025 0.025 0.82

Page 64: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

Written by: CJW Date: 04/17/2013

Reviewed by: MRB Date: 04/26/2013

Client: AEP Project: FAR Closure Project No.: CHE8273 Task No.: 05.4.6

G:\CWP\CHE8273 - Stingy Run FAR Closure\5.0 Technical File\5.4 Engineering Work File\5.4.04 Final Design and PTI\5.4.6 Task 7 Dam Design\Calc Package\Draft_Dissipator Design_Narrative_04172013.docx

ATTACHMENT A

HEC-RAS Outputs and Cross Sections for 2-yr and 100-yr Storms

Page 65: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

2 yr profile

XYZ view of stilling basin and gabion (2-yr)

0 500 1000 1500 2000 2500 3000 3500 4000560

580

600

620

640

660

680Spil lway-Sti l l ing-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Main Channel Distance (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

627.903*621.936*

615.968*610 606.620* 603.241* 599.862* 596.642* 593.148* 589.653* 586.159* 583.023* 579.494* 576.053* 572.613* 569.172* 565.731* 562.24* 558.74* 555.24

555.23 552.23* 549.23* 546.23* 543.23* 540.23* 537.23* 534.23* 531.23* 528.23* 525.23* 522.23* 519.23* 516.23* 513.23* 510.23* 507.23* 504.22* 500.210* 496.212*

Spil lway-Sti l l ing-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Legend

WS 2 year

Ground

Bank Sta

Ground

Ineff

Levee

Page 66: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

XYZ of culvert (2-yr)

100yr profile

50

3.1

Spil lway-Sti l l ing-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Legend

WS 2 year

Ground

Bank Sta

Ground

Ineff

Levee

0 500 1000 1500 2000 2500 3000 3500 4000560

580

600

620

640

660

680Spil lway-Sti l l ing-ExitChannel Plan: Final-oneton 4/8/2013

Main Channel Distance (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Page 67: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

XYZ of stilling basin and gabion

630.887*624.919* 618.952*

612.984* 609.517* 606.138* 602.759* 599.38 596.143* 592.648* 589.154* 585.66 582.444 579.003* 575.562* 572.121* 568.680* 565.24 561.74* 558.24* 555.23 551.23* 547.23* 543.23* 539.23* 535.23* 531.23* 527.23* 523.23* 519.23* 515.23* 511.23* 507.23* 504.02* 500.210* 496.212*

Spil lway-Sti l l ing-ExitChannel Plan: Final-oneton 4/8/2013

Legend

WS 100 year

Ground

Bank Sta

Ground

Levee

Page 68: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

2-Year Cross Sections

Page 69: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

0 20 40 60 80 100671

672

673

674

675

676

677

678

679

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Type 1 Channel Begin

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.035 .04 .035

0 20 40 60 80 100661

662

663

664

665

666

667

668

669

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Type 1 Channel Begin Transition

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.035 .04 .035

0 20 40 60 80 100661

662

663

664

665

666

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Begin Transition Spillway

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.013 .013 .013

0 20 40 60 80 100658

659

660

661

662

663

664

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Transition to Spillway

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.013

0 10 20 30 40 50 60652

653

654

655

656

657

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Begin Spillway

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.013

0 10 20 30 40 50 60606

607

608

609

610

611

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

End Spillway, Begin Transition to Stilling Basin

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.013

Page 70: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

0 10 20 30 40 50 60596

598

600

602

604

606

608

610

612

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Front of chute blocks

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.013

0 10 20 30 40 50 60594

596

598

600

602

604

606

608

610

612

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Top back of chute blocks

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.013

0 10 20 30 40 50 60594

596

598

600

602

604

606

608

610

612

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Bottom Back of chute block

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.013

0 10 20 30 40 50 60594

596

598

600

602

604

606

608

610

612

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Bottom front of baffles

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.013

0 10 20 30 40 50 60594

596

598

600

602

604

606

608

610

612

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Top front of baffles

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.013

0 10 20 30 40 50 60594

596

598

600

602

604

606

608

610

612

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

top back of baffles

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.013

Page 71: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

0 10 20 30 40 50 60594

596

598

600

602

604

606

608

610

612

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

back of baffles

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.013

0 10 20 30 40 50 60594

596

598

600

602

604

606

608

610

612

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Front edge of sill

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.013

0 10 20 30 40 50 60598

600

602

604

606

608

610

612

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

top of sill

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.013

0 10 20 30 40 50 60 70598

600

602

604

606

608

610

612

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

End sill, begin transition exit channel

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.013

0 20 40 60 80596

598

600

602

604

606

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Bottom of first gabion, end of conrete transition, begin gravel

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.013

0 20 40 60 80598

599

600

601

602

603

604

605

606

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

top of first gabion

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.048

Page 72: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

0 20 40 60 80598

599

600

601

602

603

604

605

606

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

top back of first gabion

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.048

0 20 40 60 80596

598

600

602

604

606

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

bottom back of first gabion

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.048

0 20 40 60 80594

596

598

600

602

604

606

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

bottom back of first gabion

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.048

0 20 40 60 80594

596

598

600

602

604

606

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

bottom back of first gabion

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.045

0 20 40 60 80588

590

592

594

596

598

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.045

0 20 40 60 80584

586

588

590

592

594

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.045

Page 73: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

0 20 40 60 80580

582

584

586

588

590

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.045

0 20 40 60 80578

580

582

584

586

588

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Front of culvert

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Ineff

Bank Sta

.045

0 20 40 60 80578

580

582

584

586

588

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Ineff

Bank Sta

.045

0 20 40 60 80576

578

580

582

584

586

588

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Ineff

Bank Sta

.025

0 20 40 60 80576

578

580

582

584

586

588

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

End of culvert, begin transition to natural

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Ineff

Bank Sta

.025

0 10 20 30 40 50 60576

578

580

582

584

586

588

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

X-sec just after curve in natural channel-~1000' upstream of ter

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.025 .025 .025

Page 74: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

0 10 20 30 40 50 60 70570

575

580

585

590

595

600

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Levee

Bank Sta

.025 .025 .025

0 10 20 30 40 50 60568

570

572

574

576

578

580

Spillway-Stilling-ExitChannel Plan: Final-oneton-culvert 4/9/2013

Final x-sec.just upstream of last culvert

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 2 year

Ground

Bank Sta

.025 .025 .025

Page 75: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

100-Year Cross Sections

Page 76: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

0 20 40 60 80 100671

672

673

674

675

676

677

678

679

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

Type 1 Channel Begin

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.035 .04 .035

0 20 40 60 80 100661

662

663

664

665

666

667

668

669

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

Type 1 Channel Begin Transition

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.035 .04 .035

0 20 40 60 80 100661

662

663

664

665

666

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

Begin Transition Spillway

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.013 .013 .013

0 20 40 60 80 100658

659

660

661

662

663

664

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

Transition to Spillway

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.013

0 10 20 30 40 50 60652

653

654

655

656

657

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

Begin Spillway

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.013

0 10 20 30 40 50 60606

607

608

609

610

611

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

End Spillway, Begin Transition to Stilling Basin

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.013

Page 77: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

0 10 20 30 40 50 60596

598

600

602

604

606

608

610

612

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

Front of chute blocks

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.013

0 10 20 30 40 50 60594

596

598

600

602

604

606

608

610

612

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

Top back of chute blocks

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.013

0 10 20 30 40 50 60594

596

598

600

602

604

606

608

610

612

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

Bottom Back of chute block

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.013

0 10 20 30 40 50 60594

596

598

600

602

604

606

608

610

612

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

Bottom front of baffles

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.013

0 10 20 30 40 50 60594

596

598

600

602

604

606

608

610

612

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

Top front of baffles

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.013

0 10 20 30 40 50 60594

596

598

600

602

604

606

608

610

612

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

top back of baffles

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.013

Page 78: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

0 10 20 30 40 50 60594

596

598

600

602

604

606

608

610

612

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

back of baffles

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.013

0 10 20 30 40 50 60594

596

598

600

602

604

606

608

610

612

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

Front edge of sill

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.013

0 10 20 30 40 50 60598

600

602

604

606

608

610

612

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

top of sill

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.013

0 10 20 30 40 50 60 70598

600

602

604

606

608

610

612

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

End sill, begin transition exit channel

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.013

0 20 40 60 80596

598

600

602

604

606

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

Bottom of first gabion, end of conrete transition, begin gravel

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.013

0 20 40 60 80598

599

600

601

602

603

604

605

606

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

top of first gabion

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.048

Page 79: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

0 20 40 60 80598

599

600

601

602

603

604

605

606

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

top back of first gabion

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.048

0 20 40 60 80596

598

600

602

604

606

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

bottom back of first gabion

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.048

0 20 40 60 80594

596

598

600

602

604

606

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

bottom back of first gabion

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.048

0 20 40 60 80594

596

598

600

602

604

606

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

bottom back of first gabion

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.045

0 20 40 60 80590

592

594

596

598

600

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.045

0 20 40 60 80586

588

590

592

594

596

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.045

Page 80: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

0 20 40 60 80582

584

586

588

590

592

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.045

0 20 40 60 80578

580

582

584

586

588

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

Begin transition to natural channel

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.045

0 20 40 60 80576

578

580

582

584

586

588

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

X-sec just ds of first culvert, begin natural channel

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Levee

Bank Sta

.025 .025 .025

0 10 20 30 40 50 60576

578

580

582

584

586

588

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

X-sec just after curve in natural channel-~1000' upstream of ter

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.025 .025 .025

0 10 20 30 40 50 60 70570

575

580

585

590

595

600

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Levee

Bank Sta

.025 .025 .025

0 10 20 30 40 50 60568

570

572

574

576

578

580

Spillway-Stilling-ExitChannel Plan: 1) Final-oneton 4/8/2013

Final x-sec.just upstream of last culvert

Station (ft)

Ele

vatio

n (ft

)

Legend

WS 100 year

Ground

Bank Sta

.025 .025 .025

Page 81: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

Written by: CJW Date: 04/17/2013

Reviewed by: MRB Date: 04/26/2013

Client: AEP Project: FAR Closure Project No.: CHE8273 Task No.: 05.4.6

G:\CWP\CHE8273 - Stingy Run FAR Closure\5.0 Technical File\5.4 Engineering Work File\5.4.04 Final Design and PTI\5.4.6 Task 7 Dam Design\Calc Package\Draft_Dissipator Design_Narrative_04172013.docx

ATTACHMENT B

Stilling Basin Type III Design Schematic (USBR, 1987)

Page 82: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe
Page 83: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

Written by: CJW Date: 04/17/2013

Reviewed by: MRB Date: 04/26/2013

Client: AEP Project: FAR Closure Project No.: CHE8273 Task No.: 05.4.6

G:\CWP\CHE8273 - Stingy Run FAR Closure\5.0 Technical File\5.4 Engineering Work File\5.4.04 Final Design and PTI\5.4.6 Task 7 Dam Design\Calc Package\Draft_Dissipator Design_Narrative_04172013.docx

ATTACHMENT C

Excerpts from HEC-11 Rip-Rap Sizing Guidance

Page 84: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

4. DESIGN GUIDELINES FOR ROCK RIPRAP

As defined in chapter 2, rock riprap consists of a well graded mixture of rock, broken concrete, or other material, dumped or hand placed to prevent erosion, scour, or sloughing of a structure or embankment. In the context of this chapter, the term rock riprap is used to refer to both rock and rubble riprap.

Rock riprap is the most widely used and desirable type of revetment in the United States. The term “riprap” connotes rock riprap. The effectiveness of rock riprap has been well established where it is properly installed, of adequate size and suitable gradation. Riprap materials include quarry-run rock, rubble, or other locally available materials. Performance characteristics of rock and rubble riprap are reviewed in section 2.1.1.

This chapter contains design guidelines for the design of rock riprap. Guidelines are provided for rock size, rock gradation, riprap layer thickness, filter design, material quality, edge treatment, and construction considerations. In addition, typical construction details are illustrated. In most cases, the guidelines presented apply equally to rock and rubble riprap. Sample specifications for rock riprap are included in appendix A.

4.1 ROCK SIZE

The stability of a particular riprap particle is a function of its size, expressed either in terms of its weight or equivalent diameter. In the following sections, relationships are presented for evaluating the riprap size required to resist particle and wave erosion forces.

4.1.1 Particle Erosion

In chapter 1, riprap failure modes were identified as particle erosion, translational slide, modified slump, and slump. Translational slide, modified slump, and slump are slope or soils processes. Particle erosion is a hydraulic phenomenon which results when the tractive force exerted by the flowing water exceeds the riprap materials ability to resist motion. It is this process that the riprap design relationships presented in this section were developed for.

Two methods or approaches have been used historically to evaluate a materials resistance to particle erosion. These methods are the permissible velocity approach and the permissible tractive force (shear stress) approach. Under the permissible velocity approach the channel is assumed stable if the computed mean velocity is lower than the maximum permissible velocity. The tractive force (boundary shear stress) approach focuses on stresses developed at the interface between flowing water and materials forming the channel boundary. By Chow’s definition, permissible tractive force is the maximum unit tractive force that will not cause serious erosion of channel bed material from a level channel bed (9). Permissible tractive force methods are generally considered to be more academically correct; however, critical velocity approaches are more readily embraced by the engineering community.

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4.1.1.1 Design Relationship

A riprap design relationship that is based on tractive force theory yet has velocity as its primary design parameter is presented in equation 6. The design relationship in equation 6 is based on the assumption of uniform, gradually varying flow. The derivation of equation 6 along with a comparison with other methods is presented in appendix D. Chart 1 in appendix C presents a graphical solution to equation 6. Equation 7 can be solved using charts 3 and 4 of appendix C.

D,, = 0.001 VP / (d,$s K,‘-5) (6)

where DSO = the median riprap particle size; C = correction factor (described below);

2 = the average velocity in the main channel (ft/s (m/s));

= the average flow depth in the main flow channel (ft (m)); and K?l@& defined as:

K, = [ 1-(sin2 8/sin2$)]0-6 (7)

where

8 = the bank angle with the horizontal; and 0 = the riprap material’s angle of repose.

The average flow depth and velocity used in equation 6 are main channel values. The main channel is defined as the area between the channel banks (see Figure 17).

LEFT FLOODPLAIN RIGHT FLOODPLAIN

Figure 17 Definition sketch; channel flow distribution

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Equation 6 is based on a rock riprap specific gravity of 2.65, and a stability factor of 1.2. Equations 8 and 9 present correction factors for other specific gravities and stability factors.

where

c,, - 2.12 / (S, - 1p (8)

s, = the specific gravity of the rock riprap.

Cd = (SF / 1.2)‘e6

where SF - the stability factor to be applied.

(9)

The correction factors computed using equations 8 and 9 are multiplied together to form a single correction factor C. This correction factor, C, is then multiplied by the riprap size computed from equation 6 to arrive at a stable riprap size. Chart 2 in appendix C provides a solution to equations 8 and 9 using correction factor C.

The stability factor, SF, used in equations 6 and 9 requires additional explanation. The stability factor is defined as the ratio of the average tractive force exerted by the flow field and the riprap materials critical shear stress. As long as the stability factor is greater than 1, the critical shear stress of the material is greater than the flow induced tractive stress, the riprap is considered to be stable. As mentioned above, a stability factor of 1.2 was used in the development of equation 6.

The stability factor is used to reflect the level of uncertainty in the hydraulic conditions at a particular site. Equation 6 is based on the assumption of uniform or gradually varying flow. In many instances, this assumption is violated or other uncertainties come to bear. For example, debris and/or ice impacts, or the cumulative effect of high shear stresses and forces from wind and/or boat generated waves. The stability factor is used to increase the design rock size when these conditions must be considered. Table 1 presents guidelines for the selection of an appropriate value for the stability factor.

Table 1. Guidelines for the selection of stability factors

Condition

Stability Factor Ranae

Uniform flow; Straight or mildly curving reach (curve radius/ channel width > 30); Impact from wave action and floating debris is minimal; Little or no uncertainty in design parameters.

1.0 - 1.2

Gradually varying flow; Moderate bend curvature (30 > curve radius/channel width > IO); Impact from waves or floating debris moderate.

1.3 - 1.6

Approaching rapidly varying flow; Sharp bend curvature (10 > curve radius/channel width); Significant impact potential from floating debris and/or ice; Significant wind and/or boat generated waves (1 - 2 ft (.30 - .61 m)); High flow turbulence; Turbulently mixing flow at bridge abutments; Significant uncertainty in design parameters.

1.6 - 2.0

31

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4.1.1.2 Application

Application of the relationship in equation 6 is limited to uniform or gradually varying flow conditions. That is in straight or mildly curving channel reaches of relatively uniform cross section. However, design needs dictate that the relationship also be applicable in nonuniform, rapidly varying flow conditions often exhibited in natural channels with sharp bends and steep slopes, and in the vicinity of bridge piers and abutments.

Research efforts to define stable riprap size relationships for nonuniform, rapidly varying flow conditions have been limited. Recently work by Wang and Shen (35) and Maynord (36)has shed some light on the variability of the Shields parameter for large particle sizes in high Reynold’s Number flows. However, no definitive relationship has been presented.

To fill the need for a design relationship that can be applied at sharp bends and on steep slopes in natural channels, and at bridge abutments, it is recommended that equation 6 be used with appropriate adjustments in velocity and/or stability factor as outlined in the following sections.

Channel Bends: At channel bends modifications to the stability factor are recommended based on the ratio or curve radius to channel width (R/W) as indicated in the following:

R/W ------ ------ Stability Factor

e====r====zz==e====

> 30 1.2

30 > R/W > 10 1.3 - 1.6

< 10 1.7

SteeD Flow conditions in steep sloped channels are rarely uniform, and are characterized by high flow velocities and significant flow turbulence. In applying equation 6 to steep slope channels, care must be exercised in the determination of an appropriate velocity. When determining the flow velocity in steep sloped channels, it is recommended that equation 4 be used to determine the channel roughness coefficient. It is also important to thoughtfully consider the guidelines for selection of stability factors as presented in Table 1.

pJ&Q&&z The FHWA is currently evaluating various equations for selection of riprap at bridge piers. Present research indicates that velocities in the vicinity of the base of a pier can be related to the velocity in the channel upstream of the pier. For this reason, the interim procedure presented below is recommended for designing riprap at piers:

o Determine the Ds,-, size of the riprap using the rearranged Ishbash equation to solve for stone diameter (in feet), for fresh water:

D50 = r 1.384 V2 2 (s-l) 2g

(10)

where: D50 = average stone diameter (ft (m)) V = velocity against stone (ft/s (m/s)) S = specific gravity of riprap material g = 32.2 ft/s2 (9.8 1 m/s2)

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Page 88: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

To calculate V, first determine the velocity of flow just upstream of the pier. This may be approximated by the velocity in the contracted section. Then multiply this value by a factor of 1.5 to 2.0 to approximate the velocity of flow at the base of the pier. Please note that preliminary research by FHWA indicates that a factor of about 1.5 may be a reasonable design value.

o Provide a mat width that extends horizontally at least two times the pier width measured from the pier face.

o Place the mat below the streambed a depth equivalent to the expected scour. The thickness should be three stone diameters or more.

Abutments; When applying equation 6 for riprap design at abutments a velocity in the vicinity of the abutment should be used instead of the average section velocity. The velocity in the vicinity of bridge abutments is a function of both the abutment type (vertical, wingwalled, or spillthrough), and the amount of constriction caused by the bridge, However, information documenting velocities in the vicinity of bridge abutments is currently unavailable. Until such information becomes available, it is recommended that equation 6 be used with a stability factor of 1.6 to 2.0 for turbulently mixing flow at bridge abutments.

Please take note that the average velocity and depth used in equation 6 for riprap design at bridge constrictions for abutment protection is the average velocity and depth in the constricted cross section at the bridge. Flow profiles at bridge sections are nonuniform as indicated in Figure 17. The recommended procedure for computing the average depth and velocity at bridge constrictions is:

1. Model the reach in the vicinity of the crossing using WSPRO (38), HEC-2 (39), or some other model with bridge loss routines.

2. Compute the average depth and velocity in the constriction as the average of the depth and velocity for modeled cross sections at the entrance to, and exit from the bridge constriction (in the vicinity of cross sections 2 and 3 as illustrated in Figure 18).

In instances where resources are not available to model flow conditions at the constriction as indicated above, normal depth and its associated flow velocity for the constricted section can be used.

As outlined above, the average section flow depth and velocity used in equation 6 are main channel values. The main channel is typically defined as the area between the channel banks (see Figure 17). However, when the bridge abutments are located on th.e floodplain a sufficient distance from the natural channel banks so as not to be influenced by main channel flows, the average depth and velocity on the flood.plain within the constricted section should be used in the riprap design relationship. Most standard computerized bridge backwater routines provide the necessary depths and velocities as a part of their standard output. If hand normal depth computations are being used, the computations must consider conveyance weighted effects of both floodplain, and main channel flows. See reference 5 or standard open channel hydraulics texts for appropriate procedures.

33

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When there is no overbank flow and the bridge spillthrough abutment on the channel bank matches the slope of the main channel banks upstream and downstream, use the design procedure without modification.

4.1.2 Wave Erosion

Waves generated by wind or boat traffic have also been observed to cause bank erosion on inland waterways. The most widely used measure of riprap’s resistance to wave is that developed by Hudson (24). The so-called Hudson relationship is given by the following equation:

W,, = ( y, H3) / (2.20 [S, - 113 cot 8) (11) where

H = the wave height; and the other parameters are as defined previously.

Assuming S, = 2.65 and 7, = 165 lb/ft3 (kg/m3), equation 11 can be reduced to:

W,, = 16.7 H3/cot 8 (12)

In terms of an equivalent diameter equation 12 can be reduced to:

D,, = 0.75H/cot1f3 8 (13) Methods for estimating a design wave height are presented in section 3.6.2. Equation 13 is presented in nomograph form in chart 7 of appendix C. Equations 12 and 13 can be used for preliminary or final design when H is less than 5 ft (1.52 m), and there is no major overtopping of the embankment.

4.1.3 Ice Damage

Ice can affect riprap linings in a number of ways. Moving surface ice can cause crushing and bending forces as well as large impact loadings. The tangential flow of ice along a riprap lined channel bank can also cause excessive shearing forces. Quantitative criteria for evaluating the impact ice has on channel protection schemes are unavailable. However, historic observations of ice flows in New England rivers indicate that riprap sized to resist design flow events will also resist ice forces.

For design, consideration of ice forces should be evaluated on a case by case bases. In most instances, ice flows are not of sufficient magnitude to warrant detailed analysis. Where ice flows have historically caused problems, a stability factor of 1.2 to 1.5 should be used to increase the design rock size. Please note that the selection of an appropriate stability factor to account for ice generated erosive problems should be based on the designers experience.

34

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A-Nf’E 1 FLOW (SUEKMICAL)

1

Yn e-m

I

&TYPE IIA FLOW (PASSES THROUGH cRlrlcAL)

HYDRAULIC JUMP -----

-----__ ,,I - FLOW ‘CRITICAL DEPTH

SO

C-TYP C-TYPE II6 FLOW (PA (PASSES THROUGH GRITICAL)

------ _ _ -CflTICAL DEPTH

t

---_ I ,N.W.S.

----- --

Y” e. Y2c % YIC y2c

?/ I /////////////7/ /

D-TYPE III FLOW (SUPERCRITICAL)

Figure 18 Typical water surface profiles. through bridge constrictions for various types as indicated

(Modified from Bradley (40))

35

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4.2 ROCK GRADATION

The gradation of stones in riprap revetment affects the riprap’s resistance to erosion. The stone should be reasonably well graded throughout the riprap layer thickness. Specifications should provide for two limiting gradation curves, and the stone gradation (as determined from a field test sample) should lay within these limits. The gradation limits should not be so restrictive that production costs would be excessive. Table 2 presents suggested guidelines for establishing gradation limits. Table 3 presents six (6) suggested gradation classes based on AASHTO specifications. Form 3 (appendix C) can be used as an aid in selecting appropriate gradation limits.

It is recognized that the use of a four (4) point gradation as specified in table 2 might in some cases be too harsh a specification for some smaller quarries. If this is the case, the 85 percent specification can be dropped as is done in table 3. In most instances, a uniform gradation between Ds, and D,,, will result in an appropriate Dss.

Each load of riprap should be reasonably well graded from the smallest to the maximum size specified. Stones smaller than the specified 5 or 10 percent size should not be permitted in an amount exceeding 20 percent by weight of each load.

Table 2. Rock riprap gradation limits.

Stone Size Range*

(ft.)

1.5 D,, to 1.7 D,,

1.2 Dso to 1.4 Dso

1.0 D,, to 1.15 D,,

0.4 D,, to 0.6 D,,

Stone Weight Percent of Range Gradation

(lb) Smaller Than

3.0 w,, to 5.0 w,, 100

2.0 W,, to 2.75 W,,, 85

1.0 w,, to 1.5 w,, 50

0.1 w,, to 0.2 wso 15

36

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Table 3. Riprap gradation classes.

Riprap Class Rock Size1 Rock Size2

(ft.> (W

Percent of Riprap

Smaller Than

Facing 1.30 200 100 0.95 75 50 0.40 5 10

Light, 1.80 500 100 1.30 200 50 0.40 5 10

l/4 ton 2.25 1000 100 1.80 500 50 0.95 75 10

l/2 ton 2.85 2000 100 2.25 1000 50 1.80 500 5

1 ton 3.60 4000 100 2.85 2000 50 2.25 1000 5

2 ton 4.50 8000 100 3.60 4000 50 2.85 2000 5

1 Assuming a specific gravity of 2.65. 2 Based on AASHTO gradations.

Gradation of the riprap being placed is controlled by visual inspection. To aid the inspector’s judgment, two or more samples of riprap of the specified gradation should be prepared by sorting, weighing, and remixing in proper proportions. Each sample should weigh about 5 to 10 tons. and one sample at the construction site.

One sample should be placed at the quarry The sample at the construction site could be

part of the finished riprap blanket. These samples should be used as a frequent reference for judging the gradation of the riprap supplied.

An alternate gradation inspection procedure is to collect field samples of this riprap. Field samples should be collected at regular intervals; each sample should be evaluated to determine in place gradation.

4

CWessel
Rectangle
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45 I I I I I I I

Crushed Ledge Rock

ANGLE OF RtiPOSE @ ) IN DEGREES

35 - I I I I I I

30 I I

IO’ I 1 I I

2 I 4 7 loo

I 2 4

MEAN STONE SIZE (II&J IN FEET

Figure 33. Angle of repose in terms of mean size and shape of stone (chart 4); example 2.

73

Page 94: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

Written by: CJW Date: 04/17/2013

Reviewed by: MRB Date: 04/26/2013

Client: AEP Project: FAR Closure Project No.: CHE8273 Task No.: 05.4.6

G:\CWP\CHE8273 - Stingy Run FAR Closure\5.0 Technical File\5.4 Engineering Work File\5.4.04 Final Design and PTI\5.4.6 Task 7 Dam Design\Calc Package\Draft_Dissipator Design_Narrative_04172013.docx

ATTACHMENT D

Gabion Basket Specification, Ohio DOT

Page 95: dam...spillway, between the base of the dam and Stingy Creek Road. This calculation package describes the design of the conveyance system (spillway over dam, energy dissipator at toe

STATE OF OHIO DEPARTMENT OF TRANSPORTATION SUPPLEMENTAL SPECIFICATION 838

GABIONS April 15, 2005

838.01 Description 838.02 Material 838.03 Construction 838.04 Method of Measurement 838.05 Basis of Payment 838.01 Description. This item shall consist of furnishing and installing gabions and fill material, excavation and other work necessary to install the gabions (baskets) as shown in the plans or as directed by the Engineer. 838.02 Material. A. Basket 1. Dimension. Wire mesh baskets shall be supplied as specified on the plans. Gabions shall be supplied pre-assembled by the manufacturer in collapsed form with all appurtenances attached to the main gabion body. The horizontal width of the basket shall not be less than 36 inches (0.90 m). The horizontal length of the basket shall not be less than 72 inches (1.8 m). The gabion lengths shall be multiples (2, 3 or 4) of the horizontal width. Dimensions are subject to a tolerance limit of ±5 percent. 2. Wire Mesh. The wire shall be steel welded wire or twisted wire mesh, fabricated in such a manner that the sides, ends, lids and diaphragms can be assembled at the construction site into rectangular units. The wire for twisted wire mesh shall have a minimum nominal diameter of U.S. Steel Wire Gage No. 11 for galvanized and U.S. Steel Wire gage No. 12 for galvanized with PVC or epoxy coating. The wire shall have a minimum tensile strength of 60,000 psi (413 MPa). The mesh openings shall be 4½ inches (115 mm) maximum and the area of any mesh opening shall not exceed 10 sq. inches (6500 mm²). The twisted wire mesh shall be formed in a uniform hexagonal pattern with nonraveling double twists. The perimeter edges of the mesh for each panel shall be tied to a selvedge wire having a minimum nominal diameter of U.S. Steel Wire Gage No. 9 for galvanized and U.S. Steel Gage No. 10 for galvanized with PVC or epoxy coating so that the selvedge to mesh connector is at least the same strength as the body of the mesh. The welded wire mesh shall be formed in a nominal 3 inch by 3 inch (75 mm by 75 mm) square pattern with a resistance weld at each connection. The wire for welded wire mesh shall have a minimum nominal diameter of U.S. Steel Gage Wire No. 11 for galvanized

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and U.S. Steel Wire Gage No. 12 for galvanized with PVC or epoxy coating. The wire shall have a minimum strength of 60,000 PSI (413 MPa). The weld shear strength shall be 400 pounds (1.78 kN) for U.S. Steel Gage No. 11 wire and 300 pounds (1.33 kN) for U.S. Steel Gage No. 12 wire. The spiral binders for joining welded wire mesh panels shall be formed from coated wire having a minimum nominal diameter of U.S. Steel Wire Gage No. 12 and a minimum tensile strength of 60,000 PSI (413 MPa). The ends shall terminate with two tight complete revolutions with a half hitch or in such a manner to maintain strength during pull-apart forces. They shall have a maximum pitch of 3 inches (75 mm) 3. Joining Wire. The joints shall be tied in such a manner that strength and flexibility at the point of connection is at least equal to the mesh. The connecting wire is to meet or exceed the same specifications as the wire used in the mesh. Lacing wire for assembling baskets and interconnecting adjacent baskets and internal connecting wire for reinforcing side panels shall be coated steel wire having a minimum nominal diameter of U.S. Steel Wire Gage No. 13.5. Spiral binders for welded wire mesh shall pass through the openings and be tied at both ends. Alternate methods and fasteners for assembling baskets and interconnecting adjacent baskets in lieu of lacing wire and spiral bindings must be approved by the Engineer. Alternate fasteners must remain closed when subjected to a 600 pound (2.67 kN) tensile force while confining the maximum number of wires to be confined by the fastener gabion structure. The submitted fastener must produce a joint strength of 1400 pounds per lineal foot (20.4 kN per meter). Installation procedures, fastener test results, and gabion manufacturer’s acceptance shall be submitted for approval to the Engineer of alternate methods and fasteners. 4. Coatings. The wire shall be galvanized with a zinc coating in conformance with ASTM A 641 class 3 finish 5. When additional coating is required by the plans the galvanized wire shall be coated with fusion bonded or extruded PVC or a fusion bonded epoxy. 5. Certification. Each shipment of units to a job site shall be accompanied by a certification which states that the material conforms to the requirements of this specification. A shipment shall consist of all material arriving at the job site at substantially the same time. Submit certified test data according to 101.03.

6. Test a. Elongation - Twisted Mesh. The wire mesh shall have sufficient elasticity to permit elongation of the mesh equivalent to a minimum of 10 percent of the length of the section of the mesh under test without reducing the gage or tensile strength of the individual wire. Elongation testing shall occur prior to coating and fabrication of the mesh.

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b. Load Test - Twisted Mesh. A section of the mesh 6 ft.(1.8 m) long and not less than 3 ft.(0.90 m) wide, after first being subjected to the elongation test described above, shall withstand a load test of 6,000 pounds (26.7 kN) applied to an area of one square foot (0.093 m²) approximately in the center of the section under test. c. Single Strand Cut - Twisted Mesh. The wire mesh shall be fabricated in such a manner as to be non-raveling. This is defined as the ability to resist pulling apart at any of the twists or connections forming the mesh. d. Weld Shear - Welded Mesh. The minimum average shear value in Newtons (pounds - force) shall not be less than 35000 lbf (241 N) multiplied by the nominal area of wire (based on the diameter of the metallic coated wire) in square inches (mm²) when tested. e. Tensile Strength - Welded or Twisted Mesh. The test shall be conducted on the wire mesh in accordance with details described in ASTM A 392 except that strength shall be as listed under load test. Tensile testing shall occur prior to coating and fabrication of the mesh. f. Zinc Coating - Welded or Twisted Mesh. The test shall be conducted in accordance with details described in ASTM A 90/A 90 M. g. PVC Coating (Minimum Thickness 0.015 inches (0.38 mm) - Welded or Twisted Mesh. Specific gravity shall be 1.30 to 1.40 as specified in ASTM D 792. Hardness shall be 50 to 60 as specified ASTM D 2240. Resistance to abrasion shall be tested as per ASTM D 1242 with the loss of weight not being more than 0.195 g. Exposure to ultraviolet rays shall be tested according to ASTM D 1499 for 2000 hours at 145º F (63º C) . h. Fusion Bonded Epoxy Coating. The epoxy shall be fusion bonded in accordance with ASTM A 884. Abrasive resistance shall be tested as per ASTM D 1242 with the loss of weight not being more than 0.19 g. B. Fill 1. Size. Gabion baskets shall be filled with approved aggregate with a minimum size of 4 inches (100 mm) and a maximum size of 8 inches (200 mm) , with both stone measurements made in the greatest dimension. 2. The aggregate shall meet the requirements of 703.19.B. 838.03 Construction. A. Assembly. Assembly and erection of the baskets shall be as per manufacturer’s recommendations.

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B. Installation. The units shall be assembled and carried to the job site and placed in their proper location. For structural integrity, all adjoining empty baskets shall be connected along the perimeter of their contact surface in order to obtain a monolithic structure. C. Filling. Baskets shall be filled with stone carefully placed by hand or machine to assure alignment and avoid bulges with a minimum of voids. Along all exposed faces and edges, the outer layers of stone shall be carefully placed and packed by hand, ensuring a neat, compact, square appearance. Thirty six inch (900 mm) high gabions shall be filled in three layers, approximately one foot (300 mm) at a time. Two connecting wires or preformed stiffeners shall be placed between each layer in all cells along all exposed faces of the gabion structure. Diagonal tact ties manufactured from U.S. Steel Wire Gage No. 9 wire are acceptable. All connecting wires shall be looped around two mesh openings and the wire terminals shall be securely twisted to prevent their loosening. The hooked ends of all stiffeners shall be closed by crimping with pliers. The cells in any row shall be filled in stages so that local deformation may be avoided; that is, at no time shall a cell be filled to a depth exceeding 12 inches (300 mm) more than the adjoining cell. The last layer of stone shall be leveled with the top of the welded wire gabion to assure proper closing of the lid and provide an even surface for the next course. The last layer of stone shall be overfilled a minimum of 2 inches (50 mm) from the top of the twisted wire gabion to allow for settlement and provide an even surface for the next course. D. Lid Closing. The lids shall be closed tight over the filling until the lid meets the perimeter edges of the front and end panels. The lid of twisted mesh gabions shall be closed with an approved lid closure tool to minimize mesh deformation; single point tools (stakes or pry bars) are not permitted. The lid shall be tightly closed (laced or fastened) along all edges, ends and diaphragms in the same manner as described above for assembly. 838.04 Method of Measurement. Measurement of gabions shall be the number of cubic yards (cubic meters) of volume completed and accepted. 838.05 Basis of Payment. This item shall include the gabions, fill material, excavation, and all equipment, labor and material to completely install the basket. Payment shall be the cubic yards (cubic meters) in place and accepted. Payment shall be made under: Item Units Description 838 Cubic yard (Cubic meter) Gabions 838 Cubic yard (Cubic meter) Gabions with additional coating

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Designer Note: Put this item in the contract when recommended by the Office of Structures.