A petition to amend the Zoning District Boundary
Map shall require the filing of a fee of $150, sufficient to cover
the costs of advertising the City Council and Planning Board public
hearings and processing the petition.  The required fee is to be paid
to the City Clerk at the time of filing.  All petitions for such action
filed with the City Clerk shall be accompanied by a reproducible plan
(and 16 copies) and a report including a metes and bounds description
of said property.  A petition to amend the Zoning Ordinance shall be
accompanied by a report and filing fee in an amount of $150 as above
noted.  All plans and reports shall be the sole responsibility of the
petitioner.  Amendments filed by the City of Haverhill municipal government
shall be exempt from the fee. 

Amendment of this chapter may be initiated by submission
to the City Council of a proposed ordinance amendment by the City
Council, the Board of Appeals, the Planning Board, an owner of land
which is to be affected by the amendment, by petition of 10 registered
voters of the City or by the Merrimack Valley Planning Commission. 
The City Council shall, within 14 days of receipt of the amendment,
submit it to the Planning Board for public hearing.  The City Council
shall hold a public hearing on the proposed amendment within 65 days
after the amendment is submitted to the Planning Board by the Council. 

The Planning Board shall hold a public hearing on
the amendment within 65 days from the date the amendment is submitted
to the Board.  The recommendations of the Planning Board shall be transmitted
to the City Council no later than 21 days from the closing of said
hearing of the Board. 

After the Planning Board hearing and report, or after
21 days shall have passed after the hearing without submission of
a report by the Planning Board, the City Council may consider and
act upon the amendment.  The City Council may adopt, reject or amend
the proposed amendments within 90 days of the Planning Board's hearing. 
The amendment shall receive at least 2/3 of all members of the City
Council voting for its passage to be enacted, provided further that,
if there is filed with the City Clerk, prior to the final action of
the City Council, a written protest against the amendment stating
the reasons and duly signed by owners of 20% or more of the area of
land to be affected by such amendment or of the area of land immediately
adjacent extending 300 feet therefrom, no amendment shall be enacted
by the Council except by a three-fourths vote of all members.  Upon
failure of the Council to vote to adopt any proposed amendment within
90 days after such hearing, no action shall be taken thereon until
after a subsequent public hearing is held with notice and report as
above provided. 

No proposed zoning amendment which has been unfavorably
acted upon by the City Council shall be considered by the City Council
within two years after the date of such unfavorable action unless
the adoption of such proposed ordinance was recommended in the final
report of the Planning Board. 

No claim of invalidity of any zoning amendment arising
out of any possible defect in the procedure of adoption or amendment
shall be made in any legal proceeding, and no state, regional, county
or municipal officer shall refuse, deny or revoke any permit, approval
or certificate because of any such claim of invalidity unless within
120 days after adoption of an ordinance legal action is commenced
and notice specifying the court, parties, invalidity claimed and date
of filing is filed, together with a copy of the petition, with the
City Clerk within seven days after commencement of the actions. 

Any petition to amend this chapter which has been
submitted to the City Council may be withdrawn without prejudice by
the petitioner prior to the publication of the notice of a public
hearing thereon before the City Council, but thereafter be withdrawn
without prejudice only with the approval of the City Council.  A petition
withdrawn with prejudice shall be considered as unfavorably acted
upon. 

Except as hereinafter provided, a Zoning Ordinance
amendment shall not apply to structures or uses lawfully in existence
or lawfully begun or to a building or special permit issued before
the first publication of notice of the public hearing on such ordinance
by the Planning Board, but shall apply to any change or substantial
extension of such use, to a building or special permit issued after
the first notice of said public hearing, to any reconstruction, extension
or structural change of such structure and to any alteration of a
structure begun after the first notice of said public hearing to provide
for its use for a substantially different purpose or for the same
purpose in a substantially different manner or to a substantially
greater extent except where alteration, reconstruction, extension
or structural change to a single- or two-family residential structure
does not increase the nonconforming nature of said structure. 

Construction or operations authorized by a building
or special permit issued prior to the first publication of notice
of the public hearing on such ordinance amendment by the Planning
Board shall conform to any subsequent amendment unless the use or
construction is commenced within a period of not less than six months
after the issuance of the permit and in cases involving construction,
unless such construction is continued through to completion as continuously
and expeditiously as is reasonable in the judgment of the Board of
Appeals. 

A definitive plan, or a preliminary plan followed
within seven months by a definitive plan, when submitted to the Planning
Board for approval under the Subdivision Control Law, and written
notice of such submission has been given to the City Clerk before
the effective date of amendment the land shown on such plan shall
be governed by the applicable provisions of the Zoning Ordinance in
effect at the time of the first such submission while such plan or
plans are being processed under the Subdivision Control Law, and,
if such definitive plan or an amendment thereof is finally approved,
for five years from the date of the endorsement of such approval. 

When a plan referred to in § 81P of Chapter
41 has been submitted to the Planning Board and written notice of
such submission has been given to the City Clerk, the use of the land
shown on such plan shall be governed by applicable provisions of the
Zoning Ordinance in effect at the time of the submission of such plan
while such plan is being processed under the Subdivision Control Law,
including the time required to pursue or await the determination of
an appeal referred to in said section and for a period of three years
from the date of endorsement by the Planning Board that approval under
the Subdivision Control Law, is not required, or words of similar
import. 

The invalidity, unconstitutionality or illegality
of any provision of this chapter or boundary shown on the Zoning Map
shall not have any effect upon the validity, constitutionality or
legality of any other provision or boundary.