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Home My WebLink Abouttecp_041294TRAFFIC ENGINEERING COMMITTEE UKIAH CIVIC CENTER 300 Seminary Avenue Ukiah, California 95482 CONFERENCE ROOM 3 APRIL 12, 1994 5:30 P.M. AGENDA BEARD, KENNEDY, BUDROW, FERNANDEZ, FORD, HARRIS, AND TURNER I. CALL TO ORDER II. APPROVAL OF MINUTES: MARCH 8, 1994 III. AUDIENCE COMMENTS ON NON-AGENDA ITEMS The Traffic Engineering Committee welcomes input from the audience. In order for everyone to be heard, please limit your comments to three (3) minutes per person and not more than 10 minutes per subject. The Brown Act regulations do not allow action to be taken on audience comments. IV. DISCUSSION/ACTION ITEMS: a. Speed Zone for Talmage Road Overcrossing at State Highway 101. V. MISCELLANEOUS ITEMS a. Sta[us Report on: 1. Handicapped Parking for Courthouse 2. No Parking Zone along 953 and 955 North State Street Frontage b. Notice of Report Prepared by the Enforcement and Engineering Team of its Extension Program, University of California "Traffic Safety Evaluation Enforcement and Engineering Analysis, December 1993". VI. ADJOURNMENT BJ \TEC ABJH896 TRAFFIC ENGINEERING COMMITTEE UKIAH CITY COUNCIL CHAMBERS MARCH 8, 1994 5:30 P.M. MINUTES MEMBERS PRESENT Fernandez, William Ford, Stephen Chairman Steve Turner STAFF PRESENT Beard, Bill Budrow, Ken Kathy Kinch Recording Secretary STAFF ABSENT Hams, Michael Kennedy, Rick OTHER PRESENT Larry Nelson The Traffic Engineering Committee meeting was called to order by Chairman Turner at 5:30 P.M. Roll was taken with the results listed above. APPROVAL OF MINUTES Ken Budrow made the following correction on Page 2, Paragraph 9, add the words without nreiudice, the sentence to read: "ON A MOTION by Beard, seconded by Fernandez, it was carved by a consensus vote, the Traffic Engineering Committee deny without prejudice the request to revise three (3) 90 minute on-street parking spaces..." Chairman Turner made the following correction on Page 3, Paragraph 3, add the words series of, and the sentence Staff will proceed with the installation of "No Parking' signs on the north MINUTES OF THE TRAFFIC ENGINEERING COMMITTEE MARCH 8, 1994 1 side of Low Gap between Bush and Despina, the paragraph to read: "Ken Budrow advised the red curb on the north side on Low Gap between Bush and Despina is badly faded. The committee discussed installing a series of "No Parking" signs within this area versus repainting the red curb due to cost and maintenance. Staff will proceed with the installation of "No Parking" signs on the north side of Low Gap between Bush and Despina." ON A MOTION by Beazd, seconded by Fernandez, it was carved by a consensus vote to approve the Traffic Engineering Committee minutes of February 8, 1994, as amended. Abstain: Steve Ford. Absent: Michael Hams and Rick Kennedy. DISCUSSION/ACTION ITEMS a. Presentation of Proposed Downtown Parking Program Chairman Turner introduced Larry DeKnoblough, Redevelopment Coordinator. Larry DeKnoblough, Redevelopment Coordinator, introduced the Downtown Pazking Improvement Program is proposed in response to the Downtown Master Plan to address pazking issues in quantity and quality. He is asking for comments or suggestions from the Committee. He stated there is an excess of 1,400 parking spaces in the downtown area. The Downtown Revitalization Plan identified the most efficient and cost effective way to provide adequate parking is to maximize utilization of existing resources. EMPLOYEE PARKING: The City of Ukiah and Ukiah Redevelopment Agency shall identify and designate specific locations to provide for long-term parking for all employees working within the Downtown District as well as citizens called to jury duty. The downtown should be divided into north and south sectors with Church Street as the dividing boundary. Employees north of Church Street would be assigned to Municipal Facilities C and D which currently provides 165 spaces with a planned expansion to at least 200 spaces. Employees south of Church Street will be assigned to Municipal Facility A which provides a total of 129 spaces. INCENTIVES AND ENFORCEMENT FOR EMPLOYEE PARKING: Implementation of the employee parking program will be accomplished through mandatory employee parking permits of $15.00 per month for two years, required of businesses and employees where on-site parking is not available. To assure compliance, the fine schedule will be set on an escalating scale based on an increasing number of citation within a 12-month period. TIME ZONES: The Downtown Master Plan identified the need for reduced parking times along School Street to meet the specific needs of businesses and create high turnover of resources. Staff is proposing the entire Parking District allow athree-hour parking time limit with the exception of four to six 24-minute spaces per block along School Street, between Clay and Smith Streets. These 24-minute zones would be established on both sides of School Street. METERED PARKING: Metered parking on-street would be eliminated through the District and MINUTES OF THE TRAFFIC ENGINEERING COMMTITEE MARCH 8, 1994 Z the 116 meters removed. This is intended to enhance the aesthetic value of our streetscape improvements, reduce parking enforcement administration costs, and assist in A.D.A. compliance. PARKING FACILITY IMPROVEMENTS: Currently in the planning stage is the addition of anew lot located between Oak and School Street at Clay Street. This lot will be for general public use and serve the Plaza and Conference Center. Additional public use lots will be located at Lot B and the current lots E and F. All public use lots will be metered. Parking facility improvements include landscaping and aesthetic improvements to existing facilities, and the acquisition and the eventual construction of new facilities. Improvements to existing facilities will be accomplished through the streetscape improvement program and will include low intensity decorative security lights, enhanced pedestrian walkways, perimeter landscaping and interior tree planters. PUBLIC AWARENESS: City lots are currently identified by signage, however, landscape improvements should provide spot lighting of those signs along with security lighting throughout the lots. Informational flyers, including maps and type of parking available, should be developed and distributed throughout downtown business and as inserts in local publications. A special complimentary one-day permit should be made available to jurors to promote a positive experience to regional residents and to encourage them to shop and eat in the downtown while here on jury duty. Staff is also proposing the establishment of in-lieu parking fees within the Parking District. The purpose of these fees would be to allow property owners in possession of parcels too small to support development with on-site parking to "purchase" off-site spaces. Parking development, implementation, and administration of the Parking District will be the responsibility of the Redevelopment Agency in the course of carrying out the responsibilities of the Downtown Master Plan. Enforcement will still be the responsibility of Public Safety. The Redevelopment Agency will coordinate with the Traffic Engineering Committee in parking issues which will result in impacts to traffic circulation. FUTURE IMPROVEMENTS: Currently being proposed for the Conference Center and Plaza is a parking expansion which will combine the two existing lots located on Oak and Stephenson, the vacant lot along Clay Street, and the property at 351 Oak Street. The Master Plan calls for close monitoring of parking demand, and development of resources in response to increases in that demand. The adoption of this program will ensure greater availability of both on- and off-street parking resources and provide the foundation to meet any increasing demands in accordance with the Downtown Master Plan. Steve Ford expressed he is against reserved parking versus public use parking. MINUTES OF THE TRAFFIC ENGINEERING COMMITTEE MARCH 8, 1994 3 Bill Beard suggested Program terms such as "all of Henry Street, Oak Street and all other areas between Oak and Pine" should indicate what streets are within the Parking District. He asked if Lot B will be permit or metered parking. He advised Lot B currently is two-hour free parking. Larry DeKnoblough advised in the purchase agreement the lot will remain use time limit parking until 1997. Staff is currently discussing if the lot will be designated meter or open for public use. Bill Beard advised time limit in the downtown area was changed from two hours to 90-minutes basically due to the demand for employee parking in the downtown area. The 90-minutes zone was put into effect because an agreement or a compromise could not be reached with County employees and private business employees on discount parking in the lots, therefore, as a result the time frame was reduced to 90-minutes. He also expressed three hour time limit in the downtown area is not feasible. Employees paying for permit parking may be a big problem. Chairman Turner suggested three hour parking versus mandatory pazking permit will be difficult. He would like to see MTA bus commuters exempt from buying a parking permit because they are not utilizing parking spaces; a small number of parking spaces reserved for public use in lots primazily reserved with parking permits; concern for handicap access in the downtown area; loading zones spaces; creating an updated map of all parking areas; and bicycle components in the downtown parking. Chairman Turner inquired if the Redevelopment Agency is relieving the Traffic Engineering Committee of the obligation/responsibility of the downtown pazking. Larry DeKnoblough responded administration of parking would be the responsibility of the Redevelopment Agency and Public Safety. This allows for a more immediate and more expedient response to business needs. Any changes to on-street parking and traffic circulation will be brought forwazd to the Traffic Engineering Committee. The Redevelopment Agency is working with allocations and time zone spaces for expedient means of implementation. Bill Beard recommended the Redevelopment Agency remove all on-street parking on State Street in the downtown pazking district. Larry DeKnoblough responded there is discussion in the Downtown Master Plan to remove all on-street parking and create atwo-way turn lane on State Street and review parking needs. Discussion followed regarding long-term employee permits; Lots C and D will be utilized by County and Bank employees; will negotiate with the Post Office employees regarding parking permits; the program will go before the Downtown Master Plan Committee, to the Redevelopment Agency, and City Council; short-term parking for faster turnover; bicycle pazking and circulation; and streetscape. Larry DeKnoblough noted the proposal will be presented to the City Council by an amendment to the existing ordinance. MINUTES OF THE TRAFFIC ENGINEERING COMMITTEE MARCH 8, 1994 4 ON A MOTION by Beard, seconded by Budrow, it was carved by a consensus vote, the Traffic Engineering Committee recommend favorably that the City Council consider delegation of parking within the downtown parking area be placed with the Redevelopment Agency, and consider the recommendations made by the Traffic Engineering Committee for review by the Downtown Master Plan Parking Committee with their submittal to the City Council. b. Reconsider Request to Revise Three (3) 90 Minute On-Street Parking Spaces to 24 Minute Limited Parking alon@ West Side of School Street just South of Standley Street Chairman Turner introduced Larry DeKnoblough, Redevelopment Coordinator. Larry DeKnoblough advised this item requires a resolution establishing the 24 minute zone. Three parking spaces will be located at the south west comer Standley and School Street, and three at the north east corner of Perkins and School Streets. ON A MOTION by Budrow, seconded by Beard, it was carried by a consensus vote, the Traffic Engineering Committee recommends the request to revise three 90 minutes on-street parking spaces to 24 minute limited parking along west side of School Street just south of Standley Street be approved by the City Council. c. Request for "No Parkinf Zone" along Frontage of 953 and 955 North State Street Larry Nelson of Nelson Auto Glass Service (Lessee Chairman Turner introduced Larry Nelson, Nelson Glass. Larry Nelson, Nelson Glass, 953 North State Street, is requesting a red curb along the frontage of 953 and 955 North State Street due vehicles and delivery trucks parking along the curb on State Street creating inadequate site distance visibility of south bound traffic when exiting onto State Street. There are currently four businesses within the complex and traffic entering and exiting the driveway has increased. There is adequate on-site parking for all businesses. 953 and 955 North State Street are one parcel. The parcels for the Goodwill, E.T.'s and 953 and 955 North State are owned by the same property owner and has no objection to the red curb. Larry Nelson submitted pictures of vehicles parked on State Street located in front of 953 North State Street. Ken Budrow inquired if the business at 955 North State was informed of the request for the red curb. Mr. Nelson responded 955 North State is E.T.'s Variety and are in complete agreement for the red curb. The business also has adequate on-site parking. Bill Beard inquired if there would be an objection to red curb from the south property line of 953 North State Street to the north property line which will include the entire frontage of the Whiskey John's and E.T.'s Variety. Larry Nelson responded no. MINUTES OF THE TRAFFIC ENGINEERING COMMITTEE MARCH 8, 1994 5 Chairman Turner agreed the Traffic Engineering Committee should be involved in the review and recommendation of traffic and circulation to the City Council. Traffic has been a major issue in the last two to three major development proposals and are real issues in the long-term development. The Committee should have involvement in the process of major developments relating to traffic. He also advised he is concerned with the proposal for removal of pedestrian access along Orchard Avenue to accommodate traffic generated by the K-Mart development. AD.TOURNMENT There being no further business, the meeting adjourned at 6:50 p.m. -~ Steve Turner, Chairman ~~ ~ - ~r Kathy I inch, Recofdi g Secretdry B:1 \TEC M030894 MINUTES OF THE TRAFFIC ENGINEERING COMMITTEE MARCH 8, 1994 7 April 12, 1994 To: City of Ukiah - Traffic Engineering Committee From: Carre Brown Re: Talmage Road Overpass Speed Zone I read the public notice in the Ukiah Daily Journal last night concerning the =.peed limit on Talmage Road at the Highway 101 overpass. I use the southbound High- way 101 off-ramp every work day. Due to the realignment for merging traffic from the stop sign onto Talmage Road a safety hazard now exists. 7 urge the Committee to petition Cal Trans to change the existing 50 mph speed zone down to at least. a 35 mph zone. The visibility for both the Talmage Road west bound traffic and they off-ramp entrance at the location has been greatly reduced fior safe merging. Furthermore, Cal Trans should be requested to re- duce the speed zone along the entire length of Talmage Road which is now designated as a 50 mph. It is ex- tremely unsafe considering the increased traffic and congestion now generated on this former country road_ ~~ IVl ~H, CA 95482-5400 • ADMIN. 707/463-6200 PUBLIC SNFEfV 463-6242/6274 • fAX I 707/463-6204 • June 13. 1994 Mr. Mark Sechanek Traffic Safety Branch Chief DEPARTMENT OF TRANSPORTATION Post Office Box 3700 Eureka, California 95502 RE: REQUEST FOR SPEED ZONE CHANGE OR POSTING OF RECOMMENDED SPEED FOR TALMAGE ROAD/101 OVERCROSSING. CITY OF UKIAH/COUNTY OF MENDOCINO Deaz Mr. Sechanek: On behalf of the City's Traffic Engineering Committee, I am forwazding their request for either a speed zone change or the posting of a recommended speed at the Talmage Road/101 overcrossing. In response to citizens concerns regarding the available sight distance and posted speed zone along the Talmage/101 overcrossing at the recently realigned south bound Talmage off-ramp, the City's Engineering Staff conducted a study of existing conditions. We believe our findings indicate that the safe stopping sight distance along Talmage given the length of the vertical curve is approximately 266 feet. A 35 MPH design speed is appropriate for this stopping sight distance. The current speed zone for west bound traffic at the overpass is 40 MPH. Enclosed are Staffs calculations for your review. Your consideration of this request is appreciated. /C_./ 'cam\}~.~-,~/~ ick H. Kennedy Director of Public Works/City Engineer cc: Charles L. Rough, Jr. City Manager Steve Turner, Chairman Traffic Engineering Committee Bob Sawyer Director of Planning RKK:kk BJ \TEC ISECNANIX "We Are Here To Serve' STAFF REPORT DATE: April 6, 1994 TO: Traffic Engineering Committee FROM: Rick Kennedy, Director of Public Works/City Engineer RE: SPEED ZONE FOR TALMAGE ROAD OVERCROSSING AT STATE HIGHWAY 101 In response to concerns regarding the available sight distance and posted speed zone along the Talmage/101 overcrossing at the newly re-aligned southbound 101 off-ramp, Engineering Staff conducted a study of existing conditions. Our analysis was performed in conformance with adopted standards published in the Caltrans Highway Design Manual. Our findings indicate that the safe stopping sight distance along Talmage given the length of the vertical curve is approximately 266 feet. A 35 M.P.H. design speed is appropriate for this stopping sight distance (based on eye height of 3.5 feet and object height of 0.5 feet). Staff also reviewed corner sight distance and intersection approach speed criteria. It is estimated that a driver stopped at the off-ramp can detect a westbound vehicle on Talmage anywhere between the range of 220 feet and 320 feet from the intersection depending upon the distance the stopped vehicle is from the centerline of the intersecting road (based on eye height of 3.5 feet and object height of 4.5 feet). Given this range for a comer sight distance, a design speed of 30 M.P.H. would be applicable, however, the criteria established for corner sight distance is based on a 7 1/2 second time period allowed for a left turning vehicle. The off-ramp is marked for right turn only and a No Left Turn sign has been installed. Therefore, this criteria would not be applicable and the stopping sight distance would control. Sight distances criteria related to intersection approach speed are appropriate only when there are no intersection controls such as yield sign, stop sign or traffic signal. Although within the City limit, this portion of Talmage Road is under the jurisdiction of the State of California. It is recommended that the Traffic Engineering Committee direct Staff to submit a written request to Caltrans requesting that the speed zone in the vicinity of the Talmage/101 overcrossing be changed from the current 40 M.P.H. zone to a 35 M.P.H. zone. 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M * ° u ~ °,oa yY m .~ ~~ ~ A y b 0 ~ a N ~ b 1. ~ ~ ~" N T N : ,T .! ab ~ O ' V N R* ° _ _ a t ti ~ ,G ~ ~~ ~ ,~ r o ~ e3 pl' h y __... _._ ._ ... _. _Y ~ b b ~i °~ ~ ~ b C, '/.0.20'/. t 4 b 0 ~ hti. 0 n n Ai LINE ~ s ~! v N , JE o m ~ ~ `Q~ .i Q H 3 4 f 6 7 8 1... _3_ 4 3 6 7 8 9 gp / 2 6' 908 .~ ,. ,~ HIGHWAY DESIGN MANUAL CHAPTER 200 GEOMETRIC DESIGN AND STRUCTURE STANDARDS Topic 201 -Sight Distance Indea 201.1 -General Sight distance is the continuous length of highway ahead visible to the driver. Three types oC s1ghC distance are considered here: passing, stopping, and decision. Stopping sight distance is the minimum sight distance to be provided on multllane highways and on 2-lane roads when passing sight distance is not eco- nomically oblalnable. Stopping sight distance also is to be provided for all elements of inter- changes and lnlerscctlons al grade, Including private road connections (see Indexes 405.1, 504.1 and Figure 405.7). Decision sight dis- tance is used at maJor decision points (see In- dexes 201.7 and 504.2). The following table shows the standards for passing and stopping sight distance related to design speed. These are the minimum values that shall be used In design. r- Table 201.1 Sight Distance Standards Design Speedll) Stopping(2) Passing (mph) (ft) (It) 20 ..........125 ...... 800 25..........150...... 950 30..........200...... 1100 35..........250...... 1300 40 ..........300 ...... 1500 45..........360...... 1650 50 ..........430 ...... 1800 55..........500...... 1950 60..........580...... 2100 65..........660...... 2300 70..........750...... 2500 75..........840...... 2600 80..........930...... 2 700 200-1 July 1, 1990 Chapter III oC "A Policy on Geometric Design of Highways and Streets," AASHTO, 1984, con- tains athorough discussion of the derivation of stopping sight distance. 201.2 passing Sight Distance Passing sight distance is the minimum sight distance required for the driver of one vehicle to pass another vehicle safely and comfortably. Passing must be accomplished without reduc- ing the speed of an oncoming vehicle traveling at the design speed should it come into view after the overtaking maneuver is started. The sight distance available for passing at any place is the longest distance at which a driver whose eyes are 3.5 feet above the pavement surface can see the lop of an object 4.25 feet high on the road., Passing sight dlslance is considered only ou 2-lane roads. AL critical locations, a stretch of 3- or 4-lane passing section wlih stopping sight distance is sometimes more economical than two lanes with passing sight distance (see Index 204.4). Figure 201.2 shows graphically the rela- tionship among length of vertical curve, design speed, and algebrale dltference lrr grades. Any one factor can be determined when the other two are known. See Chapter 6 of the Traffic Manual for cri- teria relating to barrier strtping of no-passing zones. 201.3 Stopping Sight Distance The minimum stopping sight distance is the distance requfred by the driver of a vehicle, traveling at a given speed, to bring his vehicle to a stop oiler an obJect on the road becomes visi- ble. Stopping sight dlslance is measured from the drivers eyes, which are assumed to be 3.5 feet above the pavement surface, to an obJect 0.5-fool high on ttre road. The stooping sight distances In Table 201.1 should be increased by 20% on sustained downgrades steeoer than 3% and longer than 1 male. (I) Sce Taplc 101 for selection of design speed. (2) Increase by 2096 on auatalned downgrades >396 & > 1 mile. 200-2 January, 1987 HIGHWAY DESIGN MANUAL Figure 201.2 Passing Sight Distance on Crest Vertical Curves Helpht of eye-3.60 /e et. Height of oblect-4.26 feet. F ti z w U w ti o_ 1 I 1 I w 0 a ¢ ! z , w U z , w w 2.1 LL O U ~ 1.1 m w O J Q NOTE: See Index 204.4 for vertical curve formulas DESIQN SPEED M.P.H. SIGHT DISTANCE FEET 30 1100 40 1600 60 1800 fio ---- 70 -- 2_100 -- 2500 ~-- L=CURVE LENGTH - FEET A=ALQEBRAIC GiRADE DIFFERENCE - % 3=310HT DISTANCE - FEET V=DESIGN SPEED - M.P.H. FOR 'S' WHEN S 1 L WHEN S< L 2 L = 2S- 3OA93 L = 093 rL0 25 1 1 U1 In ~r O~ 8 . ~ ~ 9 O ~ . ' 9 e 00 1 y,~ ~g0~ 9~ ~ 1500 0 S' 85 ~ ~ g' ~ 1800 L~ s' 9 0 5 ~ S' ~p0 ~ Ss2 ~ 5 ~' ~\ ~ O S'23 500 ,2 /( ~ S TOo S,2 S ~< 1 0 30 35 ao 45 50 55 80 85 -/ O S () 600 1000 1600 2000 2600 3000 3600 4000 4600 6000 LENGTH OF VERTICAL CURVE -- FEET x a w w o. y z r, rn w D HIGHWAY DESIGN MANUAL 200-3 July 1, 1990 201.4 Stopping Sight Distance at Grade horizontal sight distance restrictions. See Index Crests 203.2 for additional comments on glare screens. Figure 201.4 shows graphically the rela- tionship among length of vertical curve, design speed, and algebraic difference in grades. Any one factor can be determined when the other two are known. Cuts may be widened where vegetation re- stricting horizontal sight distance is expected to grow on finished slopes. Widening is an eco- nomic trade-off that must be evaluated along with other options. See Index 902.2 for sight distance requirements on landscape projects. 201.6 Stopping Sight Distance at Grade sags From the curves in Figure 201.5, the min- imum length of vertical curve which provides headlight sight distance in grade sags for a given design speed can be obtained. If head- ]lght sight distance is not obtainable at grade sags, llghting may be considered. 201.8 Stopping Sight Distance on Horizon- tal Curves Where an obJect off the pavement such as a bridge pier, bullding, cut slope, or natural growth restricts sight distance, the minimum radius of curvature is determined by the stop- ping sight dLStance. Stopping sight distance on horizontal curves is obtained from Figure 201.6. It is assumed that the driver's eye is 3.5 feet above the center of the inside lane (inside with respect to curve) and the obJect >s 0.5 feet high. The line of sight is assumed to intercept the view obstruction at the midpoint of the sight line and 2 feet above the center of the inside lane. This assumes there is little or no vertical curvature. The clear distance (m) >s measured from the center of the inside lane to the obstruction. The general problem >s to determhie the re- quired clear distance from centerline of inside lane to a retaining wall, bridge pier, abutment, cut slope, or other obstruction for a given de- sign speed. Using radius of curvature and sight distance for the design speed, Figure 201.6 gives the clear distance (m) from centerline of Inside lane to the obstruction. When the design speed and the cleaz dis- tance to a fixed obstruction aze known, this fig- ure also glues the required minimum radius which satisfies these conditions. See Index 101.1 for technical reductions In design speed caused by partial or momentary 201.7 Decision Sight Distance At certain locations, sight distance greater than stopping sight distance is desirable to al- low drivers time for decisions without making last minule erratic maneuvers (see Chapter III of "A Policy on Geometric Design of Highways and Streets:' AASHTO, 1984). On freeways and expressways the decision sight distance values in Table 201.7 should be used at lane drops and at oil-ramp noses to in- terchanges branch connections roadside rests vista Dolnts and inspection stations. Sight distance is measured using the 3.5- foot eye height and 0.5-foot object height. See Index 504.2 for sight distance at secondary ex- its on acollector-distributor road. Table 201.7 Decision Sight Distance Design Speed Decision Sight (mph) Distance (tt) 60 and under ....... 1000 70 ..............1100 80 .............. 1200 Topic 202 - Superelevation 202.1 Basic Criteria According to the laws of mechanics, when a vehicle travels on a curve it is forced outward by centrifugal force. On a superelevated highway, this force is resisted by the vehicle weight component parallel to the superelevated surface and side 200-4 HIGHWAY DESIGN MANUAL May 2, 1988 Figure 201.4 Stopping Sight Distance on Crest Vertical Curves Height of eye-3.60 feet. Height o} ob)ect-0.60 feet. NOTE: • Before using this chart for intersections, branch connections and exits, see Index 201.7, 405.1 and 504.2. • See Figure 204.4 for vertical curve formulae. L =CURVE LENGTH -FEET A =ALGEBRAIC GRADE DIFFERENCE - % S = 810HT DISTANCE -FEET V = DESIQN SPEED -M.P.H. FOR `S' K =DISTANCE IN FEET REQUIRED TO ACHIEVE A 1% GRANDE IN GRADE. K VALUE SHOWN IS VALID WHEN S<L. WHEN S>L WHEN S<L 2 See Index 204.4 for minimum L=2S - t3A 8 L = 1329 length of vertical curve. 16 F W 14 U ~ 13 W a 12 tt h ~ 10 a ~ a c~ z e W ~ U Z w s w LL 6 LL ~ 4 U Q 3 m 2 W f7 J 1 0 DESIGN SPEED -- M.P.H. N N M t7 0~ by d0 h~ 6~ 55 ~O 15 ~0 0 200 400 800 800 1000 1200 1400 1800 1800 2000 2200 2400 2800 2800 3000 LENGTH OF VERTICAL CURVE -- FEET I O J IQ °I " y II O O O 1 /N tV ~ y g 90 0~ I y // ti 5 b g ~~ h O ~ n p m p~ y~5 i 0 0 s N •- ,~'~ ~ s ~ ~,y$o s Y 1 `~- ~ g 50 6 ~' 25 5, S0 t g g2 ,1 S' K% ~ $ q0 ~ 3 2 S Ly ~ S- g30 5 5 K 3 `, ;g51 ~ \ K \ ~ S° L 400-8 July 1, 1990 HIGHWAY DESIGN MANUAL Topic 405 -Intersection Design Standards 405.1 Sight Distance (1) Stopping Sight Distance. See Index 201.1 for minhnum stopping sight distance re- quirements. (2) Comer Sight Distance. (a) Public Road Intersecllons--At unsignallzed public road intersections (see Index 405.7) a substantially clear line of sight should be maintained between the driver of a vehicle waiting at the cross road and the driver of an approaching vehicle in the right lane of the main highway. Sight distance values given In Table 405.1A should be used at unsl nallzed oubllc road mtersecltons. On 2-lane highways, these.valuea allow 7-1/2 seconds for the driver on the crossroad to tum left while the approaching vehicle .__.. fravels'at'the assumed design speed. of the math highway. On mundane highways, a 7-1~2 second criterion for the outside lane normally wlll provide Increased sight dis- tance to the inside lanes to compensate for the longer distance traveled by the left- lurning vehicle. Consideration should be given to increasing these values on down- grades steeper t}tan 3°rfi and longer than 1 mile (see Index 201.3). In some cases the cost to obtain 7-_IL sec- ond cocnei• sl~ht distances may,Fbe_eacces- sive. 1I1g11 costs might Include right of way, building removal, extensive excavation, or environmental costs such as tree removal, avoidance of wetlands, historic, and ar- chaeological sites. In such cases a lesser value for corner sight distance may be used, but the minimum value shat be the stopping sight distance given in Table 201.1 measured from a 9.8-foot eye height on the minor road to a 4.25- foot object height on the mbar road. bet back for the driver on the cross road shell be a minimum of 15 feet from edge of the traveled way. Set back assumes 6 feet to the stop bar, 1-foot for the width oC the stop bar, and 8 feet from Front bumper ,. to driver. If the stop bar is more than 6 feet from the traveled way, additional allowance should be considered. (b) sPrlvate Road Intersections--Minimum cor- ner sight distance shall be stopping sight distance as given in Table 201.1 measured from a 9.6-foot eye height on the private road to a 4.25-foot object height on the maJor road. Set back is a minimum of 15 feet, the same as for public road connections. (c) Urban Driveways--Corner sight distance requirements under (b) above do not apply to urban driveways. (3) Decision Sight Distance. At intersections where the State sign route turns or crosses an- other State route. the decision sight distance values given in Table 405.1B should be used. In comoutin~ and measuring decision sight distance. the 3.5-toot eye height and the 0.5- foot obJect height should be used, the object being locales on the side of the lnlersectlon nearest the auuroaching driver. The application of the various sight distance requirements for the dl[ferenl types oC intersec- tions is summarized lrt Table 405.1C. Table 405.1A Corner Sight Distance (7-1 /2 Second Criteria) Design Speed Corner Sight (mph) Distance (R) 30 .............330 40 ............. 440 50 ............. 550 60 ............. 660 70 ............. 770 Table 405.1 B Decision Sight Distance Design Speed Decision Sight (mph) Dlslaztce (Il) 30 ............. 450 40 ............. 600 50 ............. 750 60 .............1000