290 R.I. Code R. 290-RICR-20-00-4.16

Current through December 3, 2024

Section 290-RICR-20-00-4.16 - Control Dimensions

A. Driveway Angle, Rural and Urban (See §§ 4.16(A)(1) through (3) of this Part, Figures 1, 2, 3) - Angle measured from centerline of highway to centerline of driveway:

1. For two-way operation - 90 degrees recommended and 60 degrees minimum.

2. For one-way operation - if used by vehicles in both directions of travel on highway, same as two way use, right turn only; 60 degrees maximum and 45 degrees minimum.

3. Figure 1

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4. Figure 2

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5. Figure 3

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B. Driveway Width, Rural and Urban (See §§ 4.16(A)(1) through (3) of this Part, Figures 1, 2, 3).

1. Table: Driveway Width, Rural and Urban

Minimum Driveway Width (ft.)	Maximum Driveway Width (ft.)
Residential	10	20
Commercial	-	20 (one-way use) two-way use)

C. Edge Clearance (See §§ 4.16(A)(1) through (2) of this Part, Figures 1, 2) - All portions of the driveway shall be within frontage boundary lines. For driveways with angles of about 90 degrees, the edge clearance shall not be less than the radius of curvature 7) for the junction of the driveway and pavement edges.

3. Table: Edge Clearance

Minimum Edge Clearance (ft.)
Rural Residential	15
Rural Commercial	20
Urban Residential	2
Urban Commercial	10

D. Radius of Curvature of Junction of Driveway and Pavement Rural or Urban (See §§ 4.16(A)(1) through (3) of this Part, Figures 1, 2, 3)

1. Table: Corner Radius

Minimum Radius of Curvature (ft.)	Maximum Radius of Curvature (ft.)
Residential (Rural or Urban)	2	10
Commercial (Rural or Urban)	5	30

E. Corner Clearance (See Figure 3)

1. Where there are traffic signals at the intersection, the near side edge clearance shall be twice the far side.

2. Table: Corner Clearance

Minimum Corner Clearance (ft.)
Rural	40
Urban	20

F. Driveway Profile - (See § 4.16(F) of this Part, Figure 4)

1. Figure 4

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G. No Highway Edge Curb, Cut Section.

1. From edge of pavement to the edge of the shoulder, the gradient should be the same as the shoulder pitch.

2. From outer edge of shoulder to low point at ditch line of open culvert edge of shoulder to low point at ditch line or open culvert, maximum downward gradient, 8%

3. Beyond ditch line, maximum gradient 8% for commercial driveways, 15% for others.

H. No Highway Edge Curb, Fill Section

1. Slope across shoulder, gradient same as shoulder gradient.

2. Beyond outer edge of shoulder, maximum gradient 8% for commercial, 15% for others; vertical curve: As flat as feasible. To prevent drag, vertical curves shall not have a hump or dip greater than 6 inches within wheelbase length of 10 feet. Crest vertical curves shall not exceed a 32 inch hump in a 10 foot chord, and sag vertical curves shall not exceed a 2 inch depression in a 10 foot chord.

I. Driveways with a Two Foot Radius - All driveways with a two (2) foot radius shall have curb returns conforming to "Rhode Island Department of Transportation, Standard Details".

J. Exceptions - Exceptions to the control dimensions and general restrictions may be granted. These exceptions shall be approved by the State Highway Maintenance Operations Engineer of the Highway and Bridge Maintenance Division for all single-family residential applications; and by the Chief Engineer of the Department in all other cases.

290 R.I. Code R. 290-RICR-20-00-4.16

Amended effective 11/28/2018