Maintenance / Trucker Info / Bridge Weight Limit Map / Instructions
The South Dakota Bridge Weight Limit Map was developed to provide a basis for the
issuance of overweight permits. The map gives an indication of the load capacity of state
highways based on bridge strength. Color is used to indicate load capacity of the various
route sections. Red represents routes with the lowest capacity bridges. Black is used to
represent the highest capacity routes.
Based on the map and by using the procedure described below, a vehicle's maximum
weights (axle, axle group and gross) may be determined for the issuance of an overweight
permit. If the vehicle's weights exceed any of these maximum weights, a special
bridge load analysis will have to be performed to determine if a permit can be issued. A
special bridge load analysis may take up to ten working days to perform.
The procedure used to determine the maximum weight is a two step process. First, the
vehicle's axle weights, axle group weights and gross weight are determined based on
the Bridge Gross Weight Formula. The Bridge Gross Weight Formula is:
W = 500[LN/(N-1)+12N+36]
where:
W = weight in pounds for the axle group under consideration;
L = length in feet (rounded to the nearest foot) from center to center of the extreme axles of the group
N = number of axles in the group
The Bridge Weight Table shown below can be used to determine the weights instead of
using the formula. Weight on a single axle is limited to the lessor of 20,000 pounds or
600 pounds per inch width of tire.
Second, the weights are multiplied times a load factor to determine the maximum axle
weights, maximum axle group weights and maximum gross weight. The load factor is based on
the route color. The load factor used would be the factor for the lowest rated section of
the route to be traveled. The table below lists the load factors for the various colored
routes.
|
MAXIMUM WEIGHT LOAD FACTOR TABLE
|
Route Color
|
Load Factors
|
Unrestricted
|
Restricted
|
Red
|
Factor as listed on Map
|
Factor as listed on Map times 1.2
|
Yellow
|
1.000
|
1.200
|
Pink
|
1.083
|
1.283
|
Green
|
1.167
|
1.367
|
Blue
|
1.250
|
1.450
|
Black
|
1.333
|
1.533
|
Note that two factors are listed for each color. One factor is for restricted movement
and the other is for unrestricted movement. If the restricted movement load factor is
used, the permit must indicate that any bridge crossed on the restricted section of the
route, be crossed along centerline at five miles per hour and a front escort shall be
required to handle approaching traffic.
The following rules apply to the issuance and use of overweight
permits:
- The maximum weight on any axle cannot exceed 600 pounds per inch width of tire.
- Belly axles or axles which must be lifted during turning movements shall be disregarded.
- Five mile per hour down centerline bridge restrictions will not be required on Interstate Highways even though load factors for these restrictions are used.
- Axles spaced less than 40 inches apart will be disregarded.
The following rules do not apply to self-propelled overweight vehicles
or to overweight vehicles consisting of tow-away units:
- No overweight permit shall be issued for a 2, 3, or 4 axle vehicle to carry a load which causes the vehicle to be more than 10% overweight.
- Except for the steering axle(s), all axle groups should be uniformly overweight. Load shifting may be required anytime any axle group is 10% more overweight than any other axle group.
- Any axle within an axle group shall carry its share of the group load or be disregarded.
- All non-steering axles shall be equipped with dual tires or be disregarded.
Spring Load Restrictions: Certain highways may be subject to spring load limits
during the period of February 15 to April 30. While the spring load limits are in effect,
limited overweight permits will be issued according to the following criteria:
- The weight per axle may not exceed that allowed by the South Dakota Spring Load Restriction Map or addendum Spring Load Restriction Reports;
- The Maximum weight per axle shall be limited to the smallest of 20,000 pounds or 450 pounds per inch width of tire; and
- The weight may not exceed that allowed by the South Dakota Bridge Weight Limit Map or other overweight permit issuance criteria provided by the DOT.
Click to view an example.
|
Bridge Gross Weight Table
Axle Spacing |
Number of Axles |
- |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
13 |
Feet |
Maximum Gross
Weight - Pounds |
4 |
34,000 |
|
|
|
|
|
|
|
|
|
|
|
5 |
35,000 |
|
|
|
|
|
|
|
|
|
|
|
6 |
36,000 |
|
|
|
|
|
|
|
|
|
|
|
7 |
37,000 |
|
|
|
|
|
|
|
|
|
|
|
8 |
38,000 |
42,000 |
|
|
|
|
|
|
|
|
|
|
9 |
39,000 |
43,000 |
|
|
|
|
|
|
|
|
|
|
10 |
40,000 |
43,500 |
48,500 |
|
|
|
|
|
|
|
|
|
11 |
40,000 |
44,500 |
49,500 |
|
|
|
|
|
|
|
|
|
12 |
40,000 |
45,000 |
50,000 |
|
|
|
|
|
|
|
|
|
13 |
40,000 |
46,000 |
50,500 |
|
|
|
|
|
|
|
|
|
14 |
40,000 |
46,500 |
51,500 |
57,000 |
|
|
|
|
|
|
|
|
15 |
40,000 |
47,500 |
52,000 |
57,500 |
|
|
|
|
|
|
|
|
16 |
40,000 |
48,000 |
52,500 |
58,000 |
|
|
|
|
|
|
|
|
17 |
40,000 |
49,000 |
53,500 |
58,500 |
64,000 |
|
|
|
|
|
|
|
18 |
40,000 |
49,500 |
54,000 |
59,500 |
65,000 |
|
|
|
|
|
|
|
19 |
40,000 |
50,500 |
54,500 |
60,000 |
65,500 |
|
|
|
|
|
|
|
20 |
40,000 |
51,000 |
55,500 |
60,500 |
66,000 |
71,500 |
|
|
|
|
|
|
21 |
40,000 |
52,000 |
56,000 |
61,000 |
66,500 |
72,500 |
|
|
|
|
|
|
22 |
40,000 |
52,500 |
56,500 |
62,000 |
67,000 |
73,000 |
|
|
|
|
|
|
23 |
40,000 |
53,500 |
57,500 |
62,500 |
68,000 |
73,500 |
|
|
|
|
|
|
24 |
40,000 |
54,000 |
58,000 |
63,000 |
68,500 |
74,000 |
79,500 |
|
|
|
|
|
25 |
40,000 |
55,000 |
58,500 |
63,500 |
69,000 |
74,500 |
80,500 |
|
|
|
|
|
26 |
40,000 |
55,500 |
59,500 |
64,500 |
69,500 |
75,000 |
81,000 |
|
|
|
|
|
27 |
40,000 |
56,500 |
60,000 |
65,000 |
70,000 |
76,000 |
81,500 |
87,000 |
|
|
|
|
28 |
40,000 |
57,000 |
60,500 |
65,500 |
71,000 |
76,500 |
82,000 |
88,000 |
|
|
|
|
29 |
40,000 |
58,000 |
61,500 |
66,000 |
71,500 |
77,000 |
82,500 |
88,500 |
|
|
|
|
30 |
40,000 |
58,500 |
62,000 |
67,000 |
72,000 |
77,500 |
83,000 |
89,000 |
94,500 |
|
|
|
31 |
40,000 |
59,500 |
62,500 |
67,500 |
72,500 |
78,000 |
83,500 |
89,500 |
95,000 |
|
|
|
32 |
40,000 |
60,000 |
63,500 |
68,000 |
73,000 |
78,500 |
84,500 |
90,000 |
96,000 |
|
|
|
33 |
40,000 |
60,000 |
64,000 |
68,500 |
74,000 |
79,500 |
85,000 |
90,500 |
96,500 |
|
|
|
34 |
40,000 |
60,000 |
64,500 |
69,500 |
74,500 |
80,000 |
85,500 |
91,000 |
97,000 |
102,500 |
|
|
35 |
40,000 |
60,000 |
65,500 |
70,000 |
75,000 |
80,500 |
86,000 |
91,500 |
97,500 |
103,500 |
|
|
36 |
40,000 |
60,000 |
66,000 |
70,500 |
75,500 |
81,000 |
86,500 |
92,500 |
98,000 |
104,000 |
|
|
37 |
40,000 |
60,000 |
66,500 |
71,000 |
76,000 |
81,500 |
87,000 |
93,000 |
98,500 |
104,500 |
110,000 |
|
38 |
40,000 |
60,000 |
67,500 |
72,000 |
77,000 |
82,000 |
87,500 |
93,500 |
99,000 |
105,000 |
110,500 |
|
39 |
40,000 |
60,000 |
68,000 |
72,500 |
77,500 |
83,000 |
88,500 |
94,000 |
99,500 |
105,500 |
111,500 |
|
40 |
40,000 |
60,000 |
68,500 |
73,000 |
78,000 |
83,500 |
89,000 |
94,500 |
100,000 |
106,000 |
112,000 |
117,500 |
41 |
40,000 |
60,000 |
69,500 |
73,500 |
78,500 |
84,000 |
89,500 |
95,000 |
101,000 |
106,500 |
112,500 |
118,000 |
42 |
40,000 |
60,000 |
70,000 |
74,500 |
79,000 |
84,500 |
90,000 |
95,500 |
101,500 |
107,000 |
113,000 |
119,000 |
43 |
40,000 |
60,000 |
70,500 |
75,000 |
80,000 |
85,000 |
90,500 |
96,000 |
102,000 |
107,500 |
113,500 |
119,500 |
44 |
40,000 |
60,000 |
71,500 |
75,500 |
80,500 |
85,500 |
91,000 |
97,000 |
102,500 |
108,000 |
114,000 |
120,000 |
45 |
40,000 |
60,000 |
72,000 |
76,000 |
81,000 |
86,500 |
91,500 |
97,500 |
103,000 |
109,000 |
114,500 |
120,500 |
46 |
40,000 |
60,000 |
72,500 |
77,000 |
81,500 |
87,000 |
92,500 |
98,000 |
103,500 |
109,500 |
115,000 |
121,000 |
47 |
40,000 |
60,000 |
73,500 |
77,500 |
82,000 |
87,500 |
93,000 |
98,500 |
104,000 |
110,000 |
115,500 |
121,500 |
48 |
40,000 |
60,000 |
74,000 |
78,000 |
83,000 |
88,000 |
93,500 |
99,000 |
104,500 |
110,500 |
116,000 |
122,000 |
49 |
40,000 |
60,000 |
74,500 |
78,500 |
83,500 |
88,500 |
94,000 |
99,500 |
105,000 |
111,000 |
116,500 |
122,500 |
50 |
40,000 |
60,000 |
75,500 |
79,500 |
84,000 |
89,000 |
94,500 |
100,000 |
106,000 |
111,500 |
117,500 |
123,000 |
51 |
40,000 |
60,000 |
76,000 |
80,000 |
84,500 |
90,000 |
95,000 |
100,500 |
106,500 |
112,000 |
118,000 |
123,500 |
52 |
40,000 |
60,000 |
76,500 |
80,500 |
85,000 |
90,500 |
95,500 |
101,500 |
107,000 |
112,500 |
118,500 |
124,000 |
53 |
40,000 |
60,000 |
77,500 |
81,000 |
86,000 |
91,000 |
96,500 |
102,000 |
107,500 |
113,000 |
119,000 |
124,500 |
Axle Spacing |
Number of Axles |
- |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
13 |
Feet |
Maximum Gross
Weight - Pounds |
54 |
40,000 |
60,000 |
78,000 |
82,000 |
86,500 |
91,500 |
97,000 |
102,500 |
108,000 |
113,500 |
119,500 |
125,500 |
55 |
40,000 |
60,000 |
78,500 |
82,500 |
87,000 |
92,000 |
97,500 |
103,000 |
108,500 |
114,500 |
120,000 |
126,000 |
56 |
40,000 |
60,000 |
79,500 |
83,000 |
87,500 |
92,500 |
98,000 |
103,500 |
109,000 |
115,000 |
120,500 |
126,500 |
57 |
40,000 |
60,000 |
80,000 |
83,500 |
88,000 |
93,500 |
98,500 |
104,000 |
109,500 |
115,500 |
121,000 |
127,000 |
58 |
40,000 |
60,000 |
80,000 |
84,500 |
89,000 |
94,000 |
99,000 |
104,500 |
110,000 |
116,000 |
121,500 |
127,500 |
59 |
40,000 |
60,000 |
80,000 |
85,000 |
89,500 |
94,500 |
99,500 |
105,000 |
111,000 |
116,500 |
122,000 |
128,000 |
60 |
40,000 |
60,000 |
80,000 |
85,500 |
90,000 |
95,000 |
100,500 |
106,000 |
111,500 |
117,000 |
122,500 |
128,500 |
61 |
40,000 |
60,000 |
80,000 |
86,000 |
90,500 |
95,500 |
101,000 |
106,500 |
112,000 |
117,500 |
123,500 |
129,000 |
62 |
40,000 |
60,000 |
80,000 |
87,000 |
91,000 |
96,000 |
101,500 |
107,000 |
112,500 |
118,000 |
124,000 |
129,500 |
63 |
40,000 |
60,000 |
80,000 |
87,500 |
92,000 |
97,000 |
102,000 |
107,500 |
113,000 |
118,500 |
124,500 |
130,000 |
64 |
40,000 |
60,000 |
80,000 |
88,000 |
92,500 |
97,500 |
102,500 |
108,000 |
113,500 |
119,000 |
125,000 |
130,500 |
65 |
40,000 |
60,000 |
80,000 |
88,500 |
93,000 |
98,000 |
103,000 |
108,500 |
114,000 |
120,000 |
125,500 |
131,000 |
66 |
40,000 |
60,000 |
80,000 |
89,500 |
93,500 |
98,500 |
103,500 |
109,000 |
114,500 |
120,500 |
126,000 |
132,000 |
67 |
40,000 |
60,000 |
80,000 |
90,000 |
94,000 |
99,000 |
104,500 |
109,500 |
115,000 |
121,000 |
126,500 |
132,500 |
68 |
40,000 |
60,000 |
80,000 |
90,500 |
95,000 |
99,500 |
105,000 |
110,500 |
116,000 |
121,500 |
127,000 |
133,000 |
69 |
40,000 |
60,000 |
80,000 |
91,000 |
95,500 |
100,500 |
105,500 |
111,000 |
116,500 |
122,000 |
127,500 |
133,500 |
70 |
40,000 |
60,000 |
80,000 |
92,000 |
96,000 |
101,000 |
106,000 |
111,500 |
117,000 |
122,500 |
128,000 |
134,000 |
71 |
40,000 |
60,000 |
80,000 |
92,500 |
96,500 |
101,500 |
106,500 |
112,000 |
117,500 |
123,000 |
128,500 |
134,500 |
72 |
40,000 |
60,000 |
80,000 |
93,000 |
97,000 |
102,000 |
107,000 |
112,500 |
118,000 |
123,500 |
129,500 |
135,000 |
73 |
40,000 |
60,000 |
80,000 |
93,500 |
98,000 |
102,500 |
107,500 |
113,000 |
118,500 |
124,000 |
130,000 |
135,500 |
74 |
40,000 |
60,000 |
80,000 |
94,500 |
98,500 |
103,000 |
108,500 |
113,500 |
119,000 |
124,500 |
130,500 |
136,000 |
75 |
40,000 |
60,000 |
80,000 |
95,000 |
99,000 |
104,000 |
109,000 |
114,000 |
119,500 |
125,500 |
131,000 |
136,500 |
76 |
40,000 |
60,000 |
80,000 |
95,500 |
99,500 |
104,500 |
109,500 |
115,000 |
120,000 |
126,000 |
131,500 |
137,000 |
77 |
40,000 |
60,000 |
80,000 |
96,000 |
100,000 |
105,000 |
110,000 |
115,500 |
121,000 |
126,500 |
132,000 |
137,500 |
78 |
40,000 |
60,000 |
80,000 |
97,000 |
101,000 |
105,500 |
110,500 |
116,000 |
121,500 |
127,000 |
132,500 |
138,500 |
79 |
40,000 |
60,000 |
80,000 |
97,500 |
101,500 |
106,000 |
111,000 |
116,500 |
122,000 |
127,500 |
133,000 |
139,000 |
80 |
40,000 |
60,000 |
80,000 |
98,000 |
102,000 |
106,500 |
111,500 |
117,000 |
122,500 |
128,000 |
133,500 |
139,500 |
81 |
40,000 |
60,000 |
80,000 |
98,500 |
102,500 |
107,500 |
112,500 |
117,500 |
123,000 |
128,500 |
134,000 |
140,000 |
82 |
40,000 |
60,000 |
80,000 |
99,500 |
103,000 |
108,000 |
113,000 |
118,000 |
123,500 |
129,000 |
134,500 |
140,500 |
83 |
40,000 |
60,000 |
80,000 |
100,000 |
104,000 |
108,500 |
113,500 |
118,500 |
124,000 |
129,500 |
135,500 |
141,000 |
84 |
40,000 |
60,000 |
80,000 |
100,000 |
104,500 |
109,000 |
114,000 |
119,500 |
124,500 |
130,000 |
136,000 |
141,500 |
85 |
40,000 |
60,000 |
80,000 |
100,000 |
105,000 |
109,500 |
114,500 |
120,000 |
125,000 |
131,000 |
136,500 |
142,000 |
86 |
40,000 |
60,000 |
80,000 |
100,000 |
105,500 |
110,000 |
115,000 |
120,500 |
126,000 |
131,500 |
137,000 |
142,500 |
87 |
40,000 |
60,000 |
80,000 |
100,000 |
106,000 |
111,000 |
115,500 |
121,000 |
126,500 |
132,000 |
137,500 |
143,000 |
88 |
40,000 |
60,000 |
80,000 |
100,000 |
107,000 |
111,500 |
116,500 |
121,500 |
127,000 |
132,500 |
138,000 |
143,500 |
89 |
40,000 |
60,000 |
80,000 |
100,000 |
107,500 |
112,000 |
117,000 |
122,000 |
127,500 |
133,000 |
138,500 |
144,000 |
90 |
40,000 |
60,000 |
80,000 |
100,000 |
108,000 |
112,500 |
117,500 |
122,500 |
128,000 |
133,500 |
139,000 |
145,000 |
91 |
40,000 |
60,000 |
80,000 |
100,000 |
108,500 |
113,000 |
118,000 |
123,000 |
128,500 |
134,000 |
139,500 |
145,500 |
92 |
40,000 |
60,000 |
80,000 |
100,000 |
109,000 |
113,500 |
118,500 |
124,000 |
129,000 |
134,500 |
140,000 |
146,000 |
93 |
40,000 |
60,000 |
80,000 |
100,000 |
110,000 |
114,500 |
119,000 |
124,500 |
129,500 |
135,000 |
140,500 |
146,500 |
94 |
40,000 |
60,000 |
80,000 |
100,000 |
110,500 |
115,000 |
119,500 |
125,000 |
130,000 |
135,500 |
141,500 |
147,000 |
95 |
40,000 |
60,000 |
80,000 |
100,000 |
111,000 |
115,500 |
120,500 |
125,500 |
131,000 |
136,500 |
142,000 |
147,500 |
96 |
40,000 |
60,000 |
80,000 |
100,000 |
111,500 |
116,000 |
121,000 |
126,000 |
131,500 |
137,000 |
142,500 |
148,000 |
97 |
40,000 |
60,000 |
80,000 |
100,000 |
112,000 |
116,500 |
121,500 |
126,500 |
132,000 |
137,500 |
143,000 |
148,500 |
98 |
40,000 |
60,000 |
80,000 |
100,000 |
113,000 |
117,000 |
122,000 |
127,000 |
132,500 |
138,000 |
143,500 |
149,000 |
99 |
40,000 |
60,000 |
80,000 |
100,000 |
113,500 |
118,000 |
122,500 |
127,500 |
133,000 |
138,500 |
144,000 |
|
