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Design ManualSoil Bioengineering May 2000Page 1350-1 1350Soil Bioengineering Geotechnical Guidance — see geotechnical report for slope/soil stability. Iffurther assistance is needed, contact Regional Materials Engineer. Hydraulics Manual, M 23-03, WSDOT — for hydrology criteria. Highway Runoff Manual, M 31-16, WSDOT — for Stormwater Site Plans, Temporary Erosion and Sediment Control Plans, and best manage- ment practices. Roadside Manual, M 25-30, WSDOT — for vegetation and site preparation criteria, plant selection, design configurations, and other relatedtopics. Roadside Classification Plan, M25-31, WSDOT — policy and guidelines for roadside treatment. Contact the region’s Landscape Architect Office or the OSC Roadside and Site Development Services Unit at the Olympia Service Center. Environmental Procedures Manual, M 31-11, WSDOT — permits. Internet Bioengineering Drawings, WSDOT Homepage (http://www.wsdot.wa.gov/ eesc/ cae/design/roadside/bioeng.htm) 1350.03Uses (1)General Soil bioengineering combines the use of live plants or cuttings, dead plant material, and inert structural members to produce living, functioning land stabilization systems. This technique uses living plants to control and prevent soil erosion, sedimentation, and shallow slope instability. The bioengineered solution benefits from engineering techniques that use live plant material. Soil bioengineering methods can be cost effective and a useful mitigation solution for site specific problems. Soil bioengineering is effective in erosion control, streambank stabilization, and some upland instabilities. Soil bioengineering, like other engineering techniques, is not 1350.01General 1350.02References 1350.03Uses 1350.04Design Responsibilities and Considerations 1350.05Documentation 1350.01General Soil bioengineering is a land stabilization tech- nology applied to disturbed sites and onslope and streambank projects. A multidisciplinary partner- ship is used to implement soil bioengineering techniques. Project managers initiate and design bioengineering features by employing the exper- tise of WSDOT hydraulic engineers, geotechnical engineers, engineering geologists, landscape architects, horticulturists, biologists, water quality specialists, environmental planners, and others. Soil bioengineering for slope stabilization pro- vides additional environmental benefits such as habitat enhancement and water qualityimprovement. All soil bioengineering proposals should include consideration of slope geometry, climate, water regime, soil properties, and surrounding vegeta- tion. Applications of soil bioengineering are divided into three general categories: erosion control, streambank or shoreline stabilization, andupland slope stabilization. Refer to manuals according to therelated discipline. 1350.02References For more detailed information, see: Design Manual chapters, M 21-01, WSDOT: 1300Roadside Development 510Investigation of Soils, Rock, and Surfacing Materials 640Geometric Cross Section 1210Hydraulics 1130Retaining Walls Soil Bioengineering Design Manual Page 1350-2 May 2000 applicable in all situations. Soil bioengineering techniques may not effectively mitigate severe bridge scour, severe roadway erosion conditions, or deep seated slope instabilities. In such cases, soil bioengineering can be used in combination with other engineering techniques. The use of native vegetation that is adapted to the conditions of the project site will increase the success of the application of soil bioengineering techniques. Over time, native vegetation will encourage the establishment of a diverse plant community and discourage undesirable and invasive plant species. Other applications of soil bioengineering include: • Wildlife and fisheries habitat enhancement • Reinforcement and steepening of cut and fill slopes to limit impacts to adjacent properties and sensitive areas • Vegetated buffer enhancement on steep slopes • Enhancement of stormwater treatment areas and stabilization of drainage ways by provid- ing erosion prevention and sediment control • Site specific mitigations using standard geotechnical solutions in combination with vegetative control (2) Erosion Prevention Soil Bioengineering techniques can provide erosion prevention in the top soil layers. Erosion is the detachment and transport of surficial soil particles through the action of water, wind, and ice. Plant shoots and foliage diminish rainfall erosion and remove excess moisture through transpiration. Roots reinforce the soil mantle, allowing the system to grow more stable with age. Vegetative material slows down runoff and traps soil thereby reversing the effects of erosion. Refer to the Roadside Manual for more information. (3) Streambank Stabilization Soil bioengineering techniques can be used to stabilize streambanks, enhance wildlife habitat, improve water quality by controlling sediments, and protect structures. Bioengineering in the riparian zone (banks of streams, wetlands, lakes, or tidewater) requires an hydraulic study of stream characteristics and changes in stream alignment. Refer to the Hydraulics Manual for more information. (4) Upland Slope Stabilization (generally less than one meter in depth) Upland slope stabilization refers to the use of vegetation and plant materials to reduce or prevent soil erosion caused by wind or water on slopes not directly adjacent to riparian zones. There are three classifications of unstable slopes: • Surface movement refers to surface erosion caused by wind or water on slopes • Shallow-seated instability is defined as a failure surface less than one meter in depth • Deep-seated instability is defined as a failure surface greater than one meter in depth Soil bioengineering is used for slopes that are at risk of shallow landslides, slumps, sloughing, and surface erosion. Soil bioengineering techniques are most applicable to shallow slope stabilization projects characterized by unstable slopes that have surface movement. Surface movement of soils can be induced by soil creep, repeated freeze-thaw cycles, and soil erosion. The pro- cesses that influence overall slope stability, such as heavy and prolonged erosion and continuous slow soil movement, can significantly alter slope geometry. Soil bioengineering alone is not appropriate for deep-seated landslides, but can be used in conjunction with other engineering methods to treat associated shallow instabilities. Soil bioengineering techniques can be used to stabilize the slopes of construction sites or to repair disturbed or damaged slopes. Soil bioengineering is applied to both cut and fill slopes. Soil Bioengineering Design Manual Page 1350-4 May 2000 (2) Streambank/Shoreline Stabilization  Hydraulics Report, Hydraulics Manual  Roadside Restoration Plan, region’s Landscape Architecture Office or the OSC Roadside and Site Development Unit (3) Upland Slope Stabilization  Geotechnical Report, Design Manual  Geotechnical Report, Geotechnical Branch  Roadside Restoration Plan, region’s Landscape Architecture Office or the OSC Roadside and Site Development Unit P65:DP/DMM13 Design ManualRight of Way Considerations June 1999Page 1410-1 1410Right of Way Considerations •Easements that indicate other affected ownerships are added to the right of way/ access plan. •Arrangements are made to obtain utility, railroad, haul road, detour routes, or other essential agreements, as instructed in the Utilities Manual and the Agreements Manual. •Right of way acquisition, disposal, and maintenance is planned. •Easements and permits are planned (to accommodate activities outside of the right ofway). See Chapter 440 concerning design right of way widths. The widths may be modified based on Real Estate Services input but cannot be moved to coincide with property boundaries in anticipa- tion of a total take. Jogs in the final widths of theright of way are held to a minimum. See RightofWay Manual Chapter 6 for discussion ofremainders. All acquisition documents are processed through the Olympia Service Center Real Estate Services Office except temporary permits that are not shown on the Right of Way Plans and are not needed for the project (such as driveway connections). 1410.02References Code of Federal Regulations 23 CFR Chapter 1 part 712 subpart B, General Provisions and Project Procedures 49 CFR Part 24 Uniform Relocation Assistance and Real Property Acquisition Act of 1970 RCW 8.26, Relocation Assistance - Real Property Acquisition Policy WAC 468-100. Uniform Relocation Assistance and Real Property Acquisition Agreements Manual, M 22-99, Washington State Department of Transportation (WSDOT) Plans Preparation Manual, M 22-31, WSDOT 1410.01General 1410.02References 1410.03Special Features 1410.04Easement and Permit 1410.05Programming for Funds 1410.06Appraisal and Acquisition 1410.07Transactions 1410.08Documentation 1410.01 General Real Estate Services personnel participate in the project definition phase of a project to assist in minimizing right of way costs, defining route locations and acquisition areas, and determining potential problems and possible solutions. Due to the variables in land acquisition, the following categories of right of way costs are considered in the project definition phase. • Purchase costs (acquisition compensation). • Relocation assistance benefits payments. Other Real Estate Services staff expenses (acquisition services, relocation services, interim property management services). Right of way cost estimates are made by Real Estate Services specialists. When the parcels from which addi- tional right of way will be acquired are known, title reports (including assessors’ land areas) can be requested. Real Estate Services personnel also “make project field inspections at appropriate times throughout the development of a project to ensure adequate consideration is given to significant right of way elements involved (including possible social, economic, and environmental effects)” in accordance with 23CFR Chapter 1 part 712 subpart B and the Right of Way Manual. During plan development: • Title reports are examined for easements or other encumbrances that would reveal the existence and location of water lines, con- duits, drainage or irrigation lines, etc., that must be provided for in construction. Design Manual Right of Way Considerations June 1999 Page 1410-3 (2) Perpetual Easements Perpetual easements are shown on the right of way plans in accordance with the Plans Preparation Manual. (a) State Maintenance Easement. Used when the state is to construct a facility and provide all maintenance. Examples are slope and drainage easements. (b) Dual Maintenance Easement. Used when the state is to construct and maintain a facility and the owner is to maintain the remainder. Examples are; the surface area above a tunnel and the area behind a retaining wall or noise wall. (c) Transfer Easement. Used when an ease- ment must be acquired to replace an existing easement for a facility that is to be relocated. The region’s Real Estate Services Office obtains or prepares instruments that contain all necessary rights and provide for maintenance by the party to whom the easement will ultimately be con- veyed. Easements are conveyed when they remain within state rights of way and are replacing existing property rights. Easements are transferred only when the easement is outside the state right of way and not needed for highway purposes. The right of way/limited access plan is modified to identify the party to whom the easement will be transferred. The department cannot obtain easements for transfer across lands under the jurisdiction of the Department of Natural Resources (DNR). WSDOT cannot condemn for a transfer easement to a private party. (3) Temporary Easements Temporary easements are used when the state requires a property right of a temporary nature that involves either more than minor work or construction activities on privately owned prop- erty. In the cases where the rights required or the work to be performed is not beneficial to the property owner, just compensation may be paid. Temporary easements are usually shown on the right of way plans in accordance with the Plans Preparation Manual when the encroachment is significant; more than about 1.5 m. Consult the region’s Plans and Real Estate Services personnel for exceptions. If the easement is not mapped, mark and submit plans as described for construction permits. (4) Construction Permits Construction permits are used for temporary rights during construction and not used when WSDOT needs a perpetual right. A construction permit is recommended for rights of entry to publicly owned property. Local agencies might require the use of specific Forms when applying for these rights of entry. Regardless of the Form or its name, the region is responsible for appropriate central storage. A construction permit is only valid with the current owner and must be renegotiated if property ownership changes before construction begins. For private ownerships, a temporary construction easement is recommended. The construction permit is usually obtained without the payment of compensation (donation or mutual benefits, for example). Consult the region’s Plans and Real Estate Services personnel for exceptions. Permits are allowed where minor right of way acquisitions are obtained for intersections. Mapping requirements for a construction permit are as follows: 1. Construction permits are not shown on the right of way plan. 2. The region’s Project Coordinator’s Office is provided two sets of right of way plans with all required construction permits delineated in red. The region sends one copy of the marked plans and copies of the permits to the OSC Real Estate Services Office. These plan sheets provide the following information: • Ownership boundaries. (Confirmation of ownership and parcel boundaries may be completed by a search of county records and mapping. A formal title report is not required for construction permits.) • Parcel number assigned to each ownership. • Sufficient engineering detail to write legal descriptions. Right of Way Considerations Design Manual Page 1410-6 June 1999 Programming of Plan Funds for Appraisal Approval Plan Approval and Acquisition Limited Access Highways Appraisal and Acquisition Figure 1410-1 State Design Engineer* approves Access Report Plan for prehearing discussion with county and/or city officials. The access report plan may be used for preparation of federal-aid program data for appraisals if federal funds are to be used for right of way acquisition. It may be used for requesting advance appraisal funds through the Program Development Office for all projects with either state or federal funds. Program appraisals of total takes. (No acquisition.) State Design Engineer* approves Access Hearing Plan for use at a public access hearing. R/W information is complete. The access hearing plan may be used for the preparation of federal-aid program data for negotiations on federally funded projects, and for the preparation of true cost estimates and fund requests. Program all appraisals and acquisitions. Note: Do not appraise or purchase partial takes in areas subject to controversy. Appraise or purchase total takes only if federal design hearing requirements are met. No signature required. Results of Findings and Order Access Hearing are marked in red and green on Access Hearing plan and sent to OSC R/W Plans Branch. Program appraisals of partial takes where data is available to appraisers. Acquisition of total takes. State Design Engineer* Approves final R/W and LA plans or approves revisions to established R/W and L/A plans Program all remaining appraisals and all remaining acquisitions. Note: If appeal period is not complete, delay action in areas subject to controversy and possible appeal. Access Managed Highways R/W plan submitted to OSC R/W Plans Branch for approvsl. Program appraisals State Design Engineer* approves new R/W plans or approves revisions to established R/W plans. Program all appraisals and acquisitions. *Or a designee. PHASE 1 Access Report Plan PHASE 2 Access Hearing Plan PHASE 3 Findings and Order Plan PHASE 4 Final R/W and L/A Plan PHASE 5 Final R/W Plan ▼ ▼ ▼ 1420 Access Control Design Policy 1420.01 General 1420.02 Full Access Control Criteria 1420.03 Partial Access Control Criteria 1420.04 Modified Access Control Criteria 1420.05 Access Approaches 1420.06 Approaches Between Limited Access Highways and Adjacent Railroads 1420.07 Frontage Roads 1420.08 Multiple Use of Right of Way for Nonhighway Purposes 1420.09 Modifications to Established Limited Access Plans 1420.01 GENERAL Access control is established to preserve the safety and efficiency of specific highways and to preserve the public investment. Control is effected by acquiring rights of access from abutting property owners, and by selectively limiting approaches to the facility. Facilities thus controlled are termed limited access or access controlled highways, and are further distinguished as having full, partial, or modified access control. The number of access points per mile, spacing of interchanges or intersections, and the location of frontage roads or local road connections are determined by the functional clas- sification and importance of the highway, the character of the traffic, the present and future land use, the environ- ment and aesthetics, the highway design and operation, and the economic considerations involved. The establishment of full, partial, or modified control of access shall be considered whenever major improve- ments, reconstruction, relocation, or new facilities are required on all highways or whenever the route is shown on the Master Plan for limited access highways as planned for access control.” The reasonable cost of access control must be evaluated considering future acci- dent costs, future development, improved level of service of controlled facilities, and cost to replace the facility in the future if access control is not implemented. Because specific warrants cannot be logically or economically applied in every circumstance, the Assistant Secretary for Highways may consider exceptions upon presentation of justification for reasonable deviation from the policy. Expansion of an existing facility may be undertaken without control of access where there is no practical alternative within reasonable cost, subject to approval of a deviation by the State Project Development Engineer. The decision to defer implementation of access control shall be documented in the design report. Nothing in this policy should be construed to prevent short sections of full, partial, or modified control of access where unusual topographic, land use, or traffic conditions exist. Special design problems should be dealt with on the basis of sound engineering-economic principles. Preliminary approval of the degree of access control recommended by the district as presented in the final access plan is granted by headquarters. The final plan is approved by the Transportation Commission, after a public hearing (Chapter 1430), by the signing of a find- ings and order document. On all applicable classes of highways, except Interstate, stage development may be used, with initial construction as partial or modified control and ultimate planning for full control. Turnbacks should be located at points of logical termina- tion such that the department retains an adequate amount of right of way for maintenance of the facility and for other operational functions. 1420.02 FULL ACCESS CONTROL CRITERIA (1) Introduction Fully controlled access highways provide almost complete freedom from disruption by permitting access connections only through interchanges at selected public roads, rest areas, viewpoints, or weighing stations, and by prohibiting all crossings and private connections at grade. (2) Application Termini of access control sections should be at apparent logical points of design change. The following guides shall be used for the application of full access control on state highways: (Refer to Figure 1420-1a.) (a) Interstate. Interstate highways require full access control. (b) Principal Arterial. Unless approved for partial or modified access control on existing highways by the Assistant Secretary for Highways, principal arterial highways requiring four or more through traffic lanes within a 20-year design period require full access control. (c) Minor Arterial and Collector. Minor arterial and collector highways will not normally be considered for development to full access control standards. (3) Crossroads at Interchange Ramps The limit of access control is measured from the center line of ramps, crossroads, or parallel roads or from the terminus of transition tapers. (See Figures 1420-1b and 1c.) Design Manual 1420-1 June 1989 (Exception) Partial access control will not normally be used in urban areas, or inside corporate limits on existing principal arterial highways where traffic volumes are less than 700 DHV, if required levels of urban service, including operating speeds, can be maintained for traffic under existing and estimated future conditions, including traffic engineering oper- ational improvements. If not, the route should be relocated or reconstructed in accordance with the modified or partial access control standards. (b) Minor Arterial. Rural minor arterial highways on both new and existing location, and urban minor arterial highways on new location, requiring four or more through traffic lanes within a 20-year design period, or requiring only two through traffic lanes where the estimated traffic volumes exceed 3,000 average daily traffic within a 20-year design period, shall require partial access control; however, modified access control may be applied on existing highways when approved by the Assistant Secretary for Highways. (Exception) Partial access control normally will not be used in urban areas. Nor will it normally be used inside corporate limits on existing minor arterial highways where traffic volumes are less than 700 DHV, if required levels of service (including oper- ating speeds) can be maintained for existing and estimated future conditions. If these conditions cannot be met, the route should be relocated or reconstructed in accordance with the modified or partial access control standards. Other rural minor arterial highways with only two lanes may be considered for partial or modified con- trol of access if any of the following conditions apply: • The control can be acquired at a reasonable cost. • The route connects two highways of a higher classification. • The potential land development would result in numerous individual approaches, such as may be encountered in recreational or rapidly developing areas. • The highway traverses publicly-owned lands where access control seems desirable. (c) Collector (New Alignment). Collector highways on new location requiring four or more through traffic lanes in a 20-year design period shall require partial access control. (d) Collector (Existing). Existing collector highways will normally be considered for access control only when all of the following conditions apply: • The highway serves an area which is not directly served by a higher class of highway. • Existing or planned development will result in traffic volumes significantly higher than what would be required for access control on minor arterials. • Partial or modified access control may be estab- lished without a major impact on development of abutting properties within the constraints of zoning established at the time access control is proposed. (3) Interchanges and Intersections (a) Interchanges. See 1420.02(3). Full access control on crossroads at interchange ramps applies equally under conditions of partial control. (b) Intersections. Access control limits on a partially controlled highway should be established along the crossroad at a grade intersection for a minimum dis- tance of 300 feet from the center line of the nearest directional roadway. If a parallel road is located within 350 feet of the grade intersection, access con- trol should be established along the crossroad for the required minimum 300 feet and for an additional minimum distance of 130 feet in all directions from the center of the intersection of the parallel road and crossroad. On multilane facilities, measurements should be made from the center line of the nearest directional roadway. (Figure 1420-2b.) Modified access control with Type D and E approaches may be permitted beyond 130 feet from the center line of the highway only when the approaches already exist and cannot reasonably be relocated. Approaches closer than 130 feet will be permitted only where application of the normal standards would have a severe adverse effect on existing development and where the loca- tion is such that retention of the approaches will not seriously affect traffic operations. Grade intersections with public roads should be limited to the number permitted for the class of high- way involved (Figure 1420-2a); however, shorter intervals may be used, with approval from head- quarters, where topography or other conditions restrict the design. When intersecting roads are spaced farther apart than one per mile, median cross- ings may be considered for U-turns in accordance with Chapter 910. U-turns should be kept to a mini- mum, consistent with requirements for operation and maintenance of the highway. (4) Access Approach Criteria Access approaches on highways with partial control must be held to a minimum. Except for very large ownerships, or where terrain features will not allow the property to be served by a single approach, allow only one approach for each parcel. Where possible, locate a single approach to serve two or more parcels. Approaches should not be permitted for parcels which have reasonable access to other public roads unless the parcel has extensive high- way frontage. Approaches in excess of the standards set Design Manual 1420-3 June 1989 (a) Existing Highways. Modified access control may be established on existing highways other than Inter- state. Priority should be given to route segments where one or both of the following conditions apply: • Commercial development potential is high, but most of the adjoining property remains undevel- oped. • There is a reasonable expectation that the adjoin- ing property will be redeveloped to a more intensive land use resulting in greater traffic con- gestion. (b) Design Analysis. Selection of facilities on which modified access control may be applied is based on a design analysis including the following factors: • Traffic volumes. • Level of service. • Safety. • Level of Development Plan. • Route continuity. • Population density. • Local land use planning. • Present and potential land use. • Predicted growth rate. • Economic analysis. (c) Exceptions. Where modified access control is to be established, developed commercial areas may be excepted from control when all or most of the abut- ting property has been developed to the extent that few, if any, additional commercial approaches would be required with full development of the area. (3) Interchanges and Intersections (a) Interchanges. Access control is applied in the same manner at interchanges as on full control, see 1420.02(3). (b) Intersections. Access control limits at intersections on highways with modified control should be estab- lished along the crossroad for a minimum distance of 130 feet from the center line of a two-lane highway or for a minimum of 130 feet from the center line of the nearest directional roadway of a four-lane high- way (Figure 1420-3). Approaches, especially Type D and Type E commercial approaches, should be per- mitted within this area only when there is no reasonable alternative. (4) Access Approach Criteria The number and location of approaches on a highway, with modified access control, must be carefully planned to provide a safe and efficient highway compatible with present and potential land use. (a) Approach Types. On highways with modified access control, the following approach types may be permitted: • Type A, residential. • Type B, farm. • Type C, approaches to serve more than one owner and/or utility • Type D, commercial single (existing). • Type E, commercial double (existing). The type of access provided for each parcel shall take into consideration present and potential land use and should be based on an economic evaluation which considers the following: • Local comprehensive plans, zoning, and land use ordinances. • Property covenants and/or agreements. • City or county ordinances. • The highest and best use of the property. • Highest and best use of adjoining lands. • Change in use by merger of adjoining owner- ships. • All other factors bearing upon proper land use of the parcel. Access approach types are further defined in 1420.05. (b) Design Considerations. The following conditions are used to determine the number and location of access approaches: 1. Parcels which have access to another public road or street are not normally permitted direct access to the highway. 2. Approaches located in areas where sight limita- tions create undue hazard should be relocated or closed. 3. The number of access approaches should be held to a minimum. Access approaches are limited to one approach for each parcel of land, with the exception of extensive frontages where one approach is unreasonable or for Type E approaches which feature separate off and on approaches. 4. Joint use of access approaches shall be consid- ered, where feasible. 5. Additional approaches may be permitted for future development consistent with local zoning. 6. Existing access approaches not meeting the above criteria should be closed. (5) Location of Utilities, Bus Stops, Pedestrian Crossings, and Mailboxes (a) Utilities. Utilities location and access shall be consistent with the Utilities Accommodation Policy (WAC 468-34). Connecting utility lines between Design Manual 1420-5 June 1989 • Headquarters Land Management Office prepares and processes a deed granting the modified access rights. (3) Modifications for public grade intersections (a) Requirements. • Public grade intersections on state highways with partial access control should serve local arterials that form part of the local transportation network. • Requests for new intersections on established limited access highways must be made by or through the local governmental agency. • New intersections require full application of cur- rent access control design and spacing criteria. (b) Procedures. • District evaluates request. • District submits intersection plan for approval (Chapter 910) and right of way and limited access plan revision request (Plans Preparation Manual, M 22-31, ). Design Manual 1420-9 June 1989 • State Project Development Engineer approves intersection plan. • Assistant Secretary for Highways approves access revision. • District submits construction agreement to State Project Development Engineer (Utilities Manual). • Assistant Secretary for Highways approves con- struction agreement. (c) Valuation Determination. • When a requested public grade intersection will serve a local arterial that forms part of the local transportation network, compensation will not be required. • When a requested public grade intersection will serve only a limited area or is primarily for the benefit of a limited number of developers, compensation for access change will be addressed in the plan revision request. In situations where compensation is appropriate, value will be deter- mined as outlined in 1420.09(2)(c) above. V:DM10 [...]... 1420-1a 1420-10 Design Manual June 1989 ACCESS CONTROL FOR TYPICAL INTERCHANGE Figure 1420-1b (Metric) Design Manual March 1994 1420-11 ACCESS CONTROL AT RAMP TERMINATION Figure 1420-1c (Metric) 1420-12 Design Manual March 1994 PARTIAL ACCESS CONTROL CRITERIA Figure 1420-2a (Metric) Design Manual March 1994 1420-13 ACCESS CONTROL FOR INTERSECTION AT GRADE Figure 1420-2b (Metric) 1420-14 Design Manual March... 1420-3 (Metric) Design Manual March 1994 1420-15 1420 -16 Design Manual March 1994 ACCESS CONTROL FOR TYPICAL INTERCHANGE Figure 1420-1b Design Manual March 1994 1420-17 ACCESS CONTROL AT RAMP TERMINATION Figure 1420-1c 1420-18 Design Manual March 1994 PARTIAL ACCESS CONTROL CRITERIA Figure 1420-2a Design Manual March 1994 1420-19 ACCESS CONTROL FOR INTERSECTION AT GRADE Figure 1420-2b 1420-20 Design Manual. .. management measures • Describe the current and design year level of service at all affected locations within the study area; including local systems, existing ramps, and freeway lanes (5) Access Connections and Design Will the proposal provide fully directional interchanges connected to public roads, spaced appropriately, and designed to full design level geometric control criteria? Wherever possible,... is designed to the design level required by the appropriate Design Matrix Access spacing meets requirements in Chapter 940 The project is approved per Chapter 330 as part of the Project Summary approval process Omission of the request and decision report is justified to file with a copy sent to the state Access and Hearings Engineer Access Point Decision Report Possibly Not Required Figure 1425-2 Design. .. Point Decision Report 7 No Report Routed to Discipline Teams for Technical Review 8 OSC Design Does Geometric Review 8a OSC Design Does Access Review 8b from 9 OSC Traffic Does Operational Review 8c see next page Access Point Decision Report Flow Chart Figure 1425-3a Access Point Decision Report Page 1425-14 Design Manual May 2000 from previous page to 7 Is Report Complete and Technically Correct 9 No... legend item next page Access Point Decision Report Content and Review Levels Figure 1425-1a Design Manual May 2000 Access Point Decision Report Page 1425-11 Project Type Policy Point Support Team 1 2 3 4 5 6 Accept8 For Partial and Modified Access Control Freeways (See Chapter 1420.) New intersection or access point, partial access control R New intersection or access point, modified access control R Change... extent of reconstruction to be proposed and rules on any suggestions regarding deviations for new work that are being considered to become part of the proposal Show that all new ramp terminals will be designed to meet or exceed current state and local full design level geometric control criteria (6) Operational and Accident Analyses How will the proposal affect safety and traffic operations now and for the... the interchange/intersection to function as Design Manual May 2000 proposed For example, the local circulation system must be in place before new ramps are opened to traffic and there must be commitment to the travel demand management and transportation system management concepts included in the proposal If future reconstruction is part of the mitigation for design year level of service, the reconstruction... Traffic data developed for the design report, together with counts of existing traffic directly available from state or local records, is normally adequate Special counts of existing traffic should be obtained only if circumstances indicate that the available data is inadequate or outdated (c) Factors affecting the design of the subject highway, including discussions of: Design Manual June 1989 • • • • •... that apply to the area Each of the policy points is part of the decision report to answer the question given at the beginning of the discussion Explain the consistency of the proposed access point revision with those plans and studies, the applicable provisions of 23 CFR Part 450, and the applicable transportation conformity requirements of 40 CFR Parts 51 and 93 (1) Future Interchanges Is the proposed . 1420-1c (Metric) Design Manual 1420-13 March 1994 PARTIAL ACCESS CONTROL CRITERIA Figure 1420-2a (Metric) 1420-14 Design Manual March 1994 ACCESS CONTROL FOR INTERSECTION AT GRADE Figure 1420-2b (Metric) ACCESS. INTERSECTIONS Figure 1420-3 (Metric) Design Manual 1420-15 March 1994 1420 -16 Design Manual March 1994 ACCESS CONTROL FOR TYPICAL INTERCHANGE Figure 1420-1b Design Manual 1420-17 March 1994 ACCESS. above. V:DM10 1420-10 Design Manual June 1989 FULL ACCESS CONTROL CRITERIA Figure 1420-1a Design Manual 1420-11 March 1994 ACCESS CONTROL FOR TYPICAL INTERCHANGE Figure 1420-1b (Metric) 1420-12 Design Manual March

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