Pavement Surface Evaluation and Rating

PASERManualGravel Roads

RATING5

RATING3

RATING1

This manual is intended to assist local officials in understanding and rating the surface condition of gravel roads. It describes types and causes of distress and provides a simple system to visually rate the road segment’s condition. The rating procedure can be used ascondition data for the Wisconsin DOT local road inventory and as partof a computerized pavement management system like PASERWARE.

Produced by the T.I.C. with support from the Federal HighwayAdministration, the Wisconsin Department of Transportation, and the University of Wisconsin-Extension. The T.I.C., part of thenationwide Local Technical Assistance Program (LTAP), is a Center of the College of Engineering, Department of Engineering ProfessionalDevelopment, University of Wisconsin-Madison.

Copyright © 1989, 2002Wisconsin Transportation Information Center

432 North Lake StreetMadison, WI 53706

phone 800/442-4615fax 608/263-3160e-mail tic@epd.engr.wisc.eduURL http://tic.engr.wisc.edu

Printed on recycled paper.

Contents

Introduction 2

Gravel road evaluation 2

Surface conditions and defects 3

Evaluation 4

Crown 4

Drainage 5

Gravel layer 7

Surface deformation 8– Washboard 8– Potholes 9– Ruts 10

Surface defects 11– Dust 11– Loose aggregate 12

Rating road surface condition 13

Rating system 13

Rating 5 — Excellent 14

Rating 4 — Good 15

Rating 3 — Fair 16

Rating 2 — Poor 18

Rating 1 — Failed 19

Practical advice on rating roads 20

Donald Walker, T.I.C. Director, author

Lynn Entine, Entine & Associates, editor

Susan Kummer, Artifax, designer

PASERManual

Pavement Surface Evaluation and Rating

Gravel Roads

There are many miles of unsurfaced roads in this country. Wisconsin alone has over 22,000miles of gravel roads under the jurisdiction oflocal governments. Maintaining and improvingthese roads is a major responsibility for localgovernments.

Gravel roads may service very remote areas and very few vehicles. On the other hand it iscommon to have gravel roads providing serviceto agricultural, logging, and recreational areaswith fairly high traffic volumes. Many urbanareas also have some gravel roads. Heavy trucksand residential traffic can combine to make veryheavy demands on these unsurfaced roads.

This manual is intended to help you plan themaintenance and overall management of gravelroads. It discusses common problems and typicalrepairs. A simple system for evaluating condi-tions and rating roads is included.

The Wisconsin Transportation InformationCenter also has PASER manuals for other pave-ment types (see inside back cover). The ratingsystems are similar and compatible so that localroad agencies can work with a comprehensivecondition rating method. The rating procedurecan be used as condition data for the WisconsinDOT local road inventory (WISLR) and as part ofa computerized pavement management systemlike PASERWARE.

Taking an organized approach to roadwaymanagement has many benefits. By documen-ting the actual conditions of roads you can setrealistic budgets, make timely repairs, and setup cost effective maintenance procedures.Developing an overall plan for the roadwaysystem lets local agencies develop budgets andplan for future needs. When detailed informa-tion is available, local officials can respond more effectively to questions from the public. A planned approach is easier to explain andreceives greater public support.

Pavement Surface Evaluation and Rating

Gravel PASER ManualSeveral key steps are necessary to develop a

meaningful roadway management plan. First,you must inventory the existing condition. Thisis normally done by dividing the roadway intosegments with similar conditions. During theinventory you collect information on construc-tion history, roadway width, etc. Then you needsome method for assessing the condition of theexisting roadway. This Gravel PASER Manualuses a visual approach. Other information frommaterial sampling, testing, and traffic countscan be useful for a more detailed system plan.

Another necessary step is setting priorities forroadway improvements. You can use roadwaycondition and the local importance of theseroads to assign priorities. Then budgets can bedeveloped based on cost estimates for theprojected improvements. Since not allimprovements can be made in one year, youcan set up a multi-year budget plan. You canmake a capital improvement plan for three tofive years. Normally this is updated annually.

Gravel road evaluation

Evaluating and rating gravel roads requires adifferent perspective than similar evaluations ofasphalt or concrete pavements. This is due tothe nature of gravel roads and their variability.Surface conditions on gravel roads can changeliterally overnight. Heavy rains and local heavytraffic can dramatically change the surfacecharacteristics of gravel roads from one day tothe next. In addition, routine maintenanceactivities, such as one pass of a motor grader,could improve the surface conditions of agravel road significantly.

Since the evaluation or rating of a road couldvary depending on recent weather conditionsor recent maintenance activities, it should bebased on major factors. Detailed surfaceconditions should be secondary.

PASER Evaluation 3

The most important factors in evaluating agravel road are the road cross section, drainage,and adequacy of the gravel layer. The gravelroad cross section must contain adequate crownand good lateral drainage systems. The crownshould be approximately 6”, the adjacentditches should be deep enough to containsurface water, and the culvert systems shouldbe clean and sized to prevent any seriousimpoundment of water against the roadway.

The depth of the gravel layer will obviouslydepend on the existing soils and the amount ofheavy traffic. For most conditions, a minimumgravel thickness of 6” is required. Heavier layersare necessary for very poor soils and/or veryheavy traffic loads. Using geotextiles in verypoor subgrade soil conditions can alsosignificantly improve the performance of agravel road.

Surface distress, such as ruts and potholes,indicates a lack of strength. This could becaused by improper drainage, by lack of ade-quate gravel cover, or possibly both. Therefore,surface distress becomes an important indicatorof the primary concern for drainage and ade-quate gravel. The level of service that a gravelroad provides to the driver also depends onsmooth ride and dust control. Therefore distresssuch as washboarding, loose rock, and dust areimportant in the overall service of the road.However, these conditions are secondary sincethey can change quickly due to weather andmaintenance activities. They should not influ-ence the primary evaluation of the roadway.

It may be difficult to distinguish between apoorly maintained gravel road and anunimproved (dirt) road. The local road agencymust first decide if they plan to maintain theroad with a gravel surface or as an unimprovedroad. A minimum of 11⁄2”–2” of gravel surfac-ing is generally necessary to be considered agravel road. More gravel is needed to provide agood level of service.

Surface conditions and defects

The Gravel PASER Manual presents a methodfor visually assessing and rating the conditionsof existing roadways. It is based on under-standing the conditions and defects common ongravel roads. To set a rating you assess both theextent of problems on the road and theappropriate repairs or reconstruction needed.

It is helpful to separate the various conditionscommon to gravel roads. Five road conditionscan be used to evaluate and rate gravel roads.

CrownThe height and condition of crown, and an unrestricted slope of roadway from the center across the shoulders to the ditches.

DrainageThe ability of roadside ditches and under-road culverts to carry water away from the road.

Gravel layerAdequate thickness and quality of gravel to carry the traffic loads.

Surface deformationWashboarding, potholes and ruts.

Surface defectsDust and loose aggregate.

Each of these is described in some detail inthis manual. Assessing the condition of anactual roadway usually involves looking fordifferent combinations of conditions.

In reviewing different conditions and defects, it is important to consider their severity andextent. Generally problems begin slowly andprogressively become more serious. Slightdefects will grow into moderate and then severeconditions. At first, defects may be found in onlya few isolated places. As the condition worsens,more defects will show up on the surface.Examples in this manual will help you identifyconditions and determine both how bad theyare and how extensive they are.

EVALUATION — Crown4

CROWN

An unsurfaced road must be built sowater drains quickly off the roadway. If it is not, water stays in ponds orpuddles, soaks into the roadbed, andsoftens it. Building a crown into theroad—making the center of the roadhigher than the shoulder—enhancesdrainage. Normally, a gravel road willhave 4”– 6” of crown, or fall, from itscenter to the edge.

A roadway that has no crown willpond water. A windrow of soil or ahigh shoulder may also trap water onthe roadway and impede drainage. Insevere cases the crown is reversed—

lower than the edges—so that the roadis in a bowl shape. Naturally, this trapswater and rapidly deteriorates theroadway, especially under traffic.

Inadequate crown can be restored byregrading with a motor patrol grader.Light blading will restore minor irregu-larities. Restoring crown to a flat road-way may require complete reworking.This involves scarifying, or cutting loose,3”– 4” of gravel and reshaping thecrown. It is helpful to apply water anduse compaction to establish the crown.

If the surface gravel on the roadway is inadequate you may need to addgravel to construct a road with propercrown. Use good quality aggregate.

Hard and sound aggregate will preventthe breakdown of large aggregate intosmall particles under traffic. A propermixture of aggregate sizes (gradation) isalso important. You need an adequateamount of fines to bind the graveltogether on the road. See WisconsinTransportation Bulletins No. 4, RoadDrainage and No. 5, Gravel Roadsfor more information.

When you do routine maintenancegrading, take care to grade the roads toallow free drainage from the center ofthe road to the shoulder and into theditch. Improper grading can create asecondary ditch.

Excellent crown. No restriction to water flow from

centerline to ditch.

Poorly graded crown traps watercausing it to run down center of road.

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Flat crown with poor grading has

created secondary ditch preventing

free drainage into roadside ditch.▼

EVALUATION — Drainage 5

DRAINAGE

Roadside ditches and culverts must be able to handle surface water flow.Without adequate ditches, water willpond on the roadway and soften theroad base. The ditch must be wide anddeep enough to accommodate all thesurface water. It must slope so waterdrains and doesn’t form local ponds. A ditch bottom which is several feetbelow the top of the road is best. Thiswill provide thorough drainage of theroadbed and prevent flooding. Deeperand wider ditches may be necessary to

accommodate very heavy surface waterflow. Ditches must be maintained toprevent erosion or the buildup of debris.

Drainage across roadways is handledwith culverts or bridges. These drainagestructures must be maintained toprevent ponding and water backup.Culvert headwalls and riprap are veryhelpful in directing water flow andpreventing erosion of the roadbed.

Ditch cleaning is a routine mainte-nance procedure necessary to keepwater flowing properly. Spoil materialfrom a ditch may be used along theroadway if there is room. Major ditch

cleaning may require loading andhauling excess material. Take care tomaintain uniform ditch slopes. Seedthe soil or install additional erosioncontrol after major ditching repairs.

Roadway culverts tend to fill withdebris and silt. They must be cleanedroutinely to maintain their water carrying capacity. Replacing head-walls and riprap is also necessary to prevent erosion. Collapsed ordamaged culverts must be replaced.

Excellent drainage withwide deep ditches.

Partial drainage. Ditchand new culvert beingadded on left. Little orno drainage on right.

Good ditches.

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EVALUATION — Drainage6

DRAINAGE

Continued

Poor drainage due tolittle or no ditch, no

driveway culverts.

Shallow, narrow ditchcannot carry surfacewater causing ditch

erosion and temporaryroadway flooding.

Shallowditch andpartiallyfilledculvert.Ditch needscleaningand culvertshould belowered toallow aminimum of 12” ofaggregatecover.

No ditch. Road isactually trenched

into roadside forcingwater onto surface.

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EVALUATION — Gravel Layer 7

GRAVEL LAYER

Traffic loads require an adequate layer of gravel to carry and distribute the loads to the subsoils. The thicknessneeded will vary with the amount ofheavy traffic and the stability of thesubsoils. A minimum layer of 6” isnormally required. Heavier layers, up to10” or more, are sometimes used forheavy loads or poor soil conditions.

The gravel must be of good quality toprovide long term service. The gradationand durability of the gravel (measured by hardness and soundness testing) areimportant. A proper gradation contains a mixture of larger aggregate (1”), sand-sized aggregate, and fines. Morefines (8%–15%) are recommended for surfacing gravel than are normallyused in base gravel. See TransportationInformation Bulletin No. 5, Gravel Roads, for more information.

Little orno gravellayer.

Excellentgravellayer.

Adequate gravellayer. No ruts orpotholes.

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EVALUATION — Surface Deformation8

SURFACE DEFORMATION

Washboard

Traffic action can dislodge aggregateand create a washboard effect on the surface. This washboarding orcorrugation develops across the road,perpendicular to the direction oftraffic. It is more prevalent underheavy traffic and under loose aggregate conditions. It may alsotend to develop on hills or curves,near intersections, or in areas wheretraffic is accelerating or decelerating.Soft roadbeds and improper graderoperation can also cause washboards.

Light washboarding can beremoved with routine grading. Wash-boarding that is moderate or severeoften requires scarification, cuttingdown 3”-4”, and regrading. If there is insufficient material, new gravel will be required. Select an aggregatewith sufficient fines to resist futurewashboarding.

Since washboarding may be con-centrated at specific locations, spotregrading is often required. Take careto blend the regraded sections intothe adjoining roadway. Since moistureis needed for compaction, correctingwashboarding after a rain is moreeffective. Maintain the crown, andsuper-elevation, and match bridgesand intersections when repairing spot corrugations.

Operating a motor patrol grader at a high rate of speed can actuallycreate corrugations during routinemaintenance. Speeds below 10 mphare recommended. Proper bladeangle and pitch, and proper tireinflation, are also essential.

Severewashboarding

traps water.

Moderate washboarding in center of road.

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EVALUATION — Surface Deformation 9

Potholes

Potholes and depressions can developin the gravel or surface. They’re causedwhen surface material is worn away orsoft spots develop in underlying soils.They may fill with water and areaccelerated in roads without adequatecrown. Isolated potholes may berepaired by hand. This can involveputting granular material into theholes and compacting it.

Small, isolated potholes.Routine regrading shouldeliminate them.

Series of moderate potholesrequire scarification andregrading.

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Potholes at bridge may requirescarification and hand patching.Gravel and debris should becleaned off bridge deck.

Severe potholes covering most of road need additional gravel and regrading.

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Extensive potholes require reworkingand major regrading. It is usuallynecessary to add granular material torepair them. Scarify the area prior torepair to insure a good blend. Youmay need to reshape the road torestore a crown and make drainageimprovements to restore surfacestability and prevent future potholes.

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EVALUATION — Surface Deformation10

Ruts

Traffic can create a surface depressionor rut over a portion of a gravel road.The ruts may be caused by dislodgingsome of the surface gravel. Looseunstable gravel may be displaced bytraffic causing minor surface ruts.Severe rutting (over 3”) may be causedby weak underlying soils. Poor crownand drainage conditions weaken thebase and accelerate rutting.

Slight rutting can be removed byblading and restoring the crown. Severerutting caused by unstable subsurfacesoils will require improvements indrainage and addition of aggregate.

Rut in wheel path needs regradingto eliminate ponding and prevent further road deterioration.

Numerous ruts and very poordrainage create soft roadbedconditions and need major regrading and new aggregate.

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EVALUATION — Surface Defects 11

SURFACE DEFECTS

Dust

Traffic on dry gravel roads can generatedust. Good quality gravel used in theconstruction of gravel roads has acombination of large aggregate, sand,and fine material or binder. These finescan be picked up under the action oftraffic and become airborne.

Dust on gravel roads creates severalproblems. Visibility can be severelyrestricted under heavy dust conditions,

creating traffic safety hazards. Dust is aform of air pollution and can be veryobjectionable to nearby propertyowners. The loss of the fine materialfrom a well-graded gravel surface caneventually lead to a loss of stability.Without the fine binder material, thelarger particles become unstable andare dislodged by traffic.

Rolling and compacting a new gravelsurface will help maintain a tight andimpervious surface or crust. Undertraffic and during extended dry periodsthis crust may be disturbed and heavy

dust conditions result. Controlling dust with liquid calcium chloride orother surface treatment agents can be very helpful.

It is essential to replace the fines in the gravel mix to maintain the road and keep it stable under traffic. Fines can often be reclaimed from the shoulder edge and regraded andmixed with existing gravel. This shouldbe done as routine maintenance whilerestoring and maintaining the crown.

Heavy dust obscures vision and causes loss of roadway finematerial. A dustcontrol chemical may be advisable in areas of heavy traffic.

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EVALUATION — Surface Defects12

Loose aggregate

Loose aggregate or unstable surfacegravel conditions can develop from lossof fines through heavy dust action orfrom erosion due to an impropergradation mix of the original aggregate.Vehicles can move loose or unstableaggregate forming ridges or windrowsin the direction of traffic. Generallygravel will be moved from the wheelpath and form ridges at the center oflanes and at roadway edges. Looseaggregate can also accumulate at placeswhere vehicles frequently turn or stop.

Loose aggregate may be temporarilybladed to the shoulder although youhave to be careful not to restrictdrainage. By remixing loose aggregatewith fines from the road edge it may bepossible to produce a well graded mix.However, a severe accumulation of looseaggregate usually requires mixing withadditional well graded surface gravel.

Heavyaccumulation

of looseaggregate on

outside ofroadway.

Regrading andpossibly new

aggregate are needed.

Loose aggregate over most of road. Light grading and compaction duringwet weather would improve stabilityand develop a surface crust.

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13

Rating road surface conditionA simplified rating system hasbeen developed to help managegravel roads. It uses a scale of 1 to 5 —5 is excellent conditionand 1 is failed. In a normalprogression the road will startout in excellent condition andgradually deteriorate under theeffects of traffic and weather.Routine grading and minorpatching may be sufficient torestore the road to excellentcondition. As conditions worsen,more extensive maintenance

RATINGS ARE RELATED TO NEEDEDMAINTENANCE OR REPAIR

Rating 5 Newly constructed road. Excellent crownand drainage. No maintenance required.

Rating 4 Good crown and drainage. Routine main-tenance.

Rating 3 Roadway shows traffic effects. Needsregrading, minor ditch maintenance, andspot gravel application.

Rating 2 Road needs additional aggregate layer,major drainage improvements.

Rating 1 Travel is difficult. Complete rebuildingrequired.

Surface rating

Visible distress* General condition/treatment measures

5Excellent

No distress.Dust controlled.Excellent surface condition and ride.

New construction—or totalreconstruction. Excellent drainage.Little or no maintenance needed.

4Good

Dust under dry conditions.Moderate loose aggregate.Slight washboarding.

Recently regraded. Good crown anddrainage throughout. Adequategravel for traffic. Routine gradingand dust control may be needed.

3Fair

Good crown (3”-6”). Adequate ditches on more than 50% of roadway. Gravel layer mostly adequate but additional aggregate may be needed in some locations to correct washboarding or isolated potholes and ruts. Some culvert cleaning needed. Moderate washboarding (1”-2” deep) over 10%-25% of the area.Moderate dust, partial obstruction of vision. None or slight rutting(less than 1” deep). An occasional small pothole (less than 2” deep).Some loose aggregate (2” deep).

Shows traffic effects. Regrading(reworking) necessary to maintain.Needs some ditch improvement and culvert maintenance. Someareas may need additional gravel.

2Poor

Little or no roadway crown (less than 3”). Adequate ditches on lessthan 50% of roadway. Portions of the ditches may be filled, over-grown and/or show erosion. Some areas (25%) with little or no aggre-gate. Culverts partially full of debris. Moderate to severe washboard-ing (over 3” deep) over 25% of area. Moderate rutting (1”-3”), over10%-25% of area. Moderate potholes (2”-4”) over 10%-25% ofarea. Severe loose aggregate (over 4”).

Travel at slow speeds (less than 25 mph) is required. Needsadditional new aggregate. Majorditch construction and culvertmaintenance also required.

1Failed

No roadway crown or road is bowl shaped with extensive ponding.Little if any ditching. Filled or damaged culverts. Severe rutting (over 3” deep), over 25% of the area. Severe potholes (over 4” deep),over 25% of area. Many areas (over 25%) with little or no aggregate.

Travel is difficult and road may beclosed at times. Needs completerebuilding and/or new culverts.

* Individual road sections will not have all of the types of distress listed for any particular rating. They may have only one or two types.

may be required; completerebuilding may eventually benecessary.

To select a rating first assessthe crown, drainage, and gravellayer. Then review the individualdefects and select the type ofmaintenance or rehabilitationnecessary. The rating shouldreflect the condition and type ofmaintenance or repairs required.Look at the photographs in thissection to become more familiarwith the ratings and conditions.

Rating surface condition14

RATING 5

EXCELLENT — Little or no maintenance required

New construction with excellent crown, drainage and gravel layer. Little or no distress.

Newly constructedroad with excellent

crown, drainageand gravel layer.

Road has excellentcrown. Gravel has

been stabilized fordust control. Very

good drainage.

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Rating surface condition 15

RATING 4

GOOD — Routine maintenance may be required

Good crown, drainage and gravel layer.Distress limited to traffic effects such asdust, loose aggregate, and slightwashboarding.

Good crown, ditches,and gravel layer. Slight traffic effects,washboarding, andloose gravel.

Good crown andgravel, ditchappears goodthroughout.Occasionalroutine gradingfor traffic effects.

Plenty of crownand excellentditch. Needsroutine grading toeliminate slightsecondary ditchand loose gravel.

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Rating surface condition16

RATING 3

FAIR — Regrading and drainageimprovement, spot gravel application needed

Adequate drainage and crown on morethan 50% of roadway. Gravel layer isadequate with only need for spotreplacement. Regrading needed toimprove crown and repair wash-boarding and slight ruts or potholes.

Good gravel andcrown but ditch

partially blocked.Needs cleaning oradditional culvert.

Heavyaccumulation

of loose gravelrequires regrading.

Ditch cleaningneeded on right side.

Fair crown andgood gravel

layer. Shallowditch needs

improvement.

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Rating surface condition 17

RATING 3

FAIR — (continued) Regrading and drainageimprovement, spot gravelapplication needed

Fair crown andgravel layer.Needs ditchingon right andmore crown.

Adequatedrainage and fair crown. A fewsmall potholesindicate need forregrading andadditional gravel.

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Rating surface condition18

RATING 2

POOR — More gravel and majordrainage improvements required

Travel at slow speeds (25 mph) may benecessary. Additional gravel layerneeded to carry traffic. Little or nocrown. Ditching is inadequate on morethan 50% of roadway.

Numerous potholesindicate additional gravel

most likely required torestore crown. Needs

extensive reworking. ▼

Some gravel and crown but almost no

ditch. Drivewayculvert required.

No crown, poordrainage, andneeds gravel.

Little gravel and almost noditches or crown.

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Lack of ditchon rightcauses ruts.Needs gravel.

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Rating surface condition 19

RATING 1

Failed — Reconstruction required

Needs complete rebuilding. Travel isdifficult; road may be closed at times.

Ruts. No ditch or aggregate.

Complete failure.Restricted travel.

Deep ruts and potholes.No drainage. Travel isdifficult.

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20

Inventory and field inspection

Most agencies routinely observe road-way conditions as a part of their normalwork and travel. However, an actualinspection means looking at the entireroadway system and preparing a writtensummary of conditions. This inspectionhas many benefits over casual obser-vations. Useful comparisons betweensegments can be made and moredependable decisions are likely becausethe entire roadway system is considered.

An inspection also encourages areview of specific conditions importantin roadway maintenance—drainage andadequate strength, for example.

A simple written inventory is useful inmaking decisions where other peopleare involved. You do not have to trustyour memory, and you can usuallyanswer questions in more detail. Havinga written record also improves yourcredibility with the public.

Finally, a written inventory is veryuseful in documenting the changingroadway conditions. Without recordsextending over several years, it isimpossible to know if your road condi-tions are improving, holding their own,or declining.

Annual budgets and long rangeplanning are best done when based onactual needs as documented with awritten inventory.

The Wisconsin DOT local roadinventory (WISLR) is a valuable resourcefor managing your local roads. AddingPASER surface condition ratings is animportant improvement.

Averaging and comparing sections

For evaluation, divide the local roadsystem into individual segments whichare similar in construction and condition.Rural segments may vary from 1⁄2 mileto a mile long, while some sections inurban areas will likely be 1-4 blocks longor more. If you are starting with theWISLR inventory, the segments havealready been established. You may want

to review them for consistent roadconditions. Obviously no roadway seg-ment has entirely consistent conditions.Some “averaging” will be necessary.Also, individual road segments will nothave all of the types of distress listed forany particular rating; they may have onlyone or two. The objective is to rate thecondition that represents the majority ofthe roadway. Small or isolated condi-tions should not influence the rating. Itis useful to note these special conditionson the inventory form so this informa-tion can be used in project design. Forexample, some spot repairs may berequired.

Occasionally pavement conditions varysignificantly. For example, short sectionsof good condition may be followed bysections of poor pavement conditions. In these cases it is best to rate the pave-ment according to the worst conditionsand note the variation on the form.

The overall purpose of conditionrating is to provide a relative comparisonof the condition of all your pavementsegments. Therefore, comparing anytwo pavement segments would showthe better pavement having a higherrating. Within a given rating, say 3, notall pavements will be exactly the same.However, they should all be consideredto be in better condition than thosewith lower ratings, say 2. Sometimes itis helpful in rating a difficult segment to compare it to other previously ratedsegments. For example, if it is betterthan one you rated 2, and worse than a typical 4, then a rating of 3 is appro-priate. Having all road segments rated in the proper relative order is mostimportant and useful.

Separating road function from conditions

Gravel roads often are found in very lowvolume applications. This sometimes isconfusing. People rating roads are morewilling to accept poor condition on aroad if it is little used. In higher trafficsituations, they expect a road in bettercondition.

Therefore, there may be a tendency in evaluating the condition of a road toevaluate the condition more harshly inhigher traffic volume situations and tobe more lenient in evaluating little-usedroads. This tendency should be avoided.The evaluation of the actual roadwaycondition must be objective.

You will also consider the road’sfunction or importance but this must be done separately. Roads can be cate-gorized by their use or their function. Inselecting project improvements, you willlikely consider both the road conditionand the road’s importance to select themost needed projects.

Planning maintenance and repair

We have found that relating a normalmaintenance or rehabilitation procedureto the surface rating scheme helps localofficials use the rating system. However,an individual surface rating should notautomatically dictate the final mainte-nance or rehabilitation technique. Youshould consider safety, future trafficprojections, original construction, androadway strength since these maydictate a more comprehensive rehabi-litation than the rating suggests.

Summary

Using local road funds most efficientlyrequires good planning and accurateidentification of appropriate rehabi-litation projects. Assessing roadwayconditions is an essential first step in this process. The PASER evaluationprocedure has proven effective inimproving decision making and usinghighway funds more efficiently. It can beused directly by local officials and staff.It may be combined with additionaltesting and data collection in a morecomprehensive pavement managementsystem. For additional training andinformation, contact the WisconsinTransportation Information Center.

Practical advice on rating roads

Pavement Surface Evaluation and Rating (PASER) Manuals

Asphalt PASER Manual, 2002, 28 pp.

Brick and Block PASER Manual, 2001, 8 pp.

Concrete PASER Manual, 2002, 28 pp.

Gravel PASER Manual, 2002, 20 pp.

Sealcoat PASER Manual, 2000, 16 pp.

Unimproved Roads PASER Manual, 2001, 12 pp.

Drainage ManualLocal Road Assessment and Improvement, 2000, 16 pp.

SAFER ManualSafety Evaluation for Roadways, 1996, 40 pp.

Flagger’s Handbook (pocket-sized guide), 1998, 22 pp.

Work Zone Safety, Guidelines for Construction, Maintenance, and Utility Operations, (pocket-sized guide), 2002, 58 pp.

Wisconsin Transportation Bulletins

#1 Understanding and Using Asphalt#2 How Vehicle Loads Affect Pavement Performance#3 LCC—Life Cycle Cost Analysis#4 Road Drainage#5 Gravel Roads#6 Using Salt and Sand for Winter Road Maintenance#7 Signing for Local Roads#8 Using Weight Limits to Protect Local Roads#9 Pavement Markings

#10 Seal Coating and Other Asphalt Surface Treatments#11 Compaction Improves Pavement Performance#12 Roadway Safety and Guardrail#13 Dust Control on Unpaved Roads#14 Mailbox Safety#15 Culverts-Proper Use and Installation#16 Geotextiles in Road Construction/Maintenance and Erosion Control#17 Managing Utility Cuts#18 Roadway Management and Tort Liability in Wisconsin#19 The Basics of a Good Road#20 Using Recovered Materials in Highway Construction#21 Setting Speed Limits on Local Roads

432 North Lake StreetMadison, WI 53706

phone 800/442-4615fax 608/263-3160e-mail tic@epd.engr.wisc.eduURL http://tic.engr.wisc.edu

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