§ 44. Modification of and changes in contracts. a. The board of
transportation for and on behalf of the city, from time to time with the
consent, in writing, of the bondsmen or sureties of a person, who has
contracted with such board or its predecessors to construct, equip,
maintain or operate any road, may agree with such contractor upon
changes in and modifications of such contract, or of the plans and
specifications upon which such road is to be constructed, but no change
or modifications in the plans and specifications consented to and
authorized pursuant to section twenty-one of this chapter shall be made
without the further consent and authorization provided for in such
section.

b. The board of transportation, from time to time, but only with the
approval of the board of estimate and the mayor, may agree with railroad
companies upon changes in and modifications of the terms and conditions
of any contract under or pursuant to which any railroad, or any part
thereof, has been or is to be constructed, equipped, maintained or
operated, and with like approval such contract may be cancelled and
replaced by a new contract to include the railroads embraced in such
existing contract. The board of transportation may include therein
provision for the acquisition by the city of the railroads or any of
them or portions of any of them and is authorized and empowered on
behalf of the city to accept title thereto or control thereof and to
provide for the payment thereof through amortization or otherwise as the
board of transportation may determine.

c. Any other provision of this chapter to the contrary
notwithstanding, the board of transportation shall not make any new
contract or modify any contract for the construction, equipment,
maintenance or operation of any railroad without the approval or consent
of the board of estimate and the mayor.

d. If any contract for construction or equipment of a railroad or
section thereof has been awarded and a part of the work therein required
to be performed by the contractor has been done or is in process of
being done as to a portion of the route of such road and if another
route for a railroad has been or shall be established by the board of
transportation under section twenty of this chapter and consented to as
provided in section twenty-one of this chapter, which, or a portion of
which, in the opinion of such board should in the public interest be
substituted in place of a portion of the road to be constructed or
equipped under such contract, then the board with the consent of the
board of estimate and the mayor, as soon as the detailed plans therefor
have been prepared as prescribed in section twenty-two of this chapter,
without advertising for proposals, may agree as provided in this
subdivision with such contractor upon changes in and modifications of
his contract for the purpose of making such substitution. Such agreement
in such case may provide, in consideration, among other things, of a
surrender by the contractor of his right to construct or equip a
designated portion of the road or section or road described in his
contract, that such contractor shall complete the construction or
equipment of the remainder of the road or section described in such
contract and shall in place of the portion surrendered construct or
equip a railroad or section of a railroad upon such substituted route
and in accordance with the plans and specifications adopted therefor for
such sum of money as may be provided in such modifying agreement. As
part of the consideration of such modifying agreement, the agreement may
also provide that such contractor shall guarantee to the city, with
proper and sufficient sureties, that in the event that the city shall
enter into such modifying agreement providing for construction of such
substituted route or section thereof by the contractor, the cost to the
city of providing for the construction of any additional section of such
railroad upon such substituted route in continuation of that portion
thereof which is to be constructed by the contractor under such
modifying agreement, shall not be in excess of an amount specified in
such modifying agreement or that if the contract for construction of any
such additional section is to be awarded after advertisement for
proposals under section seventeen of this chapter, that a responsible
bidder for the construction thereof acceptable to the city shall be
obtained at a price not exceeding a specified amount.

e. If any contract for equipment, maintenance and operation of a
railroad has been made and part of the work of construction thereof has
been done or is in process of being done, and if another route for a
railroad has been or shall be established by the board of transportation
under section twenty of this chapter and consented to as provided in
section twenty-one of this chapter, which, or a portion of which, in the
opinion of the board in the public interest, should be substituted in
place of a portion of the road to be equipped and operated under such
contract, for use and operation in connection with or as part of the
route, a portion of which has been in part already constructed or is in
process of construction, then the board with the consent of the board of
estimate and the mayor may agree as provided in this subdivision with
the person having the contract for equipment, maintenance and operation
of such railroad, upon changes and modifications of such contract. Such
agreement in such case may provide, in consideration, among other
things, of the surrender by the contractor of his right to equip,
maintain and operate a designated portion of the railroad described in
his contract, that in place of the portion surrendered, he shall equip,
maintain and operate a railroad or portion of a railroad upon such
substituted route. The rental to be received by the city under such
contract, as changed and modified, representing compensation to the city
for the use of such substituted part of such railroad operated
thereunder necessarily need not be a portion of the income, earnings or
profits from the operation of the railroads combined as provided in
subdivision d or subdivision g of section forty of this chapter equal
annually, if earned, to the interest and one per centum for sinking fund
upon the amount of city bonds issued for the investment of the city in
the construction thereof but may be either a specified sum of money or a
specified part or proportion of income, earnings or profits of such
substituted road, or both a sum of money and a part or proportion of
such income, earnings or profits, or may be such portion of the income,
earnings and profits of the railroads so combined as may be provided in
such modified contract as rental for such substituted railroad and for
the other railroads of the city to be equipped, maintained and operated
under such contract as so modified.