1482                               Laws of Maryland                         Ch. 534

§ 11-803. When local authorities may and shall alter maximum
limits.

(a)    Whenever local authorities in their respective jurisdictions
determine on the basis of an engineering and traffic investigation
that the maximum speed permitted under this article is greater or
less than is reasonable and safe under the conditions found to exist
upon a highway or part of a highway, the local authority may deter-
mine and declare a reasonable and safe maximum limit thereon
which

(1)    Decreases the limit at intersections;

(2)    Increases the limit within an urban district but not to more
than 50 miles per hour; or

(3)    Decreases the limit outside an urban district, but not to less
than 35 miles per hour.

Provided that such local authorities, without an engineering and
traffic investigation may conform a posted maximum speed limit
which was lawfully in effect on the date prior to the effective date of
this part, to a different maximum lawful speed limit specified in
section 11-801 (b).

(b)    Local authorities in their respective jurisdictions shall deter-
mine by an engineering and traffic investigation the proper maxi-
mum speed for all arterial streets and shall declare a reasonable and
safe maximum limit thereon which may be greater or less than the
maximum speed permitted under this Article for an urban district.

(c)    Any altered limit established as hereinabove authorized shall
be effective when appropriate signs giving notice thereof are erected
upon the street or highway.

(d)    Any EXCEPT IN BALTIMORE, ANY alteration of maxi-
mum limits on State highways or extensions thereof in a municipality
by local authorities shall not be effective until the alteration has been
approved by the State Roads Commission.

§ 11-804. Minimum speed regulation.

(a)    No person shall willfully drive a motor vehicle at such a slow
speed as to impede the normal and reasonable movement of traffic
except when reduced speed is necessary for safe operation or in com-
pliance with law.

(b)    Whenever the State Roads Commission or local authorities
within their respective jurisdictions determine on the basis of an
engineering and traffic investigation that slow speeds on any part of
a highway impede the normal and reasonable movement of traffic,
the Commission or the local authority may determine and declare a
minimum speed limit below which no person shall drive a vehicle
except when necessary for safe operation or in compliance with law.

(c)    It is unlawful to operate upon a public highway any vehicle
or combination of vehicles, which is designed to be and is operated
at a speed of 25 miles per hour or less, unless the rearmost vehicle
displays a "slow-moving vehicle emblem," except upon vehicles used
by a utility, whether publicly or privately owned, for the construction,
maintenance, or repair of its own facilities or upon vehicles used by