The provisions contained in this article, together with the
Town drainage report, maps and charts appended thereto, which are
hereby incorporated in this article, are for the purpose of achieving
and maintaining an adequate, efficient and balanced drainage and flood
prevention system coordinated with existing and projected land uses
and in compliance with minimum protection levels to be integrated
with all public works planning, open land uses, conservation objectives,
watershed management and any community-inspired proposals designed
to promote the public welfare, but not prejudicial to or inconsistent
with the primary purpose of adequate drainage and flood hazard prevention
requirements.
Before final Planning Board approval of a development plan,
the developer shall submit drainage plans with a report containing
sufficient data for the Town Engineer to check the feasibility of
the drainage system as proposed by the developer. The following data
shall be included:
A. Hydrologic (at all critical points within the development):
(1) Tributary drainage area delineated on the map.
(5) Design flow and protection level.
B. Hydraulic:
(1) The plan and profile of all drainage systems shall be provided.
(2) Sizes and types of drainage improvements, including special structures,
typical sections, easements, width, right-of-way and fencing.
(3) When required, supporting calculations for upstream and downstream
channel capacities as they affect water surface levels and backwater
within the development. Such calculations shall be supported by such
additional survey information as may be required to determine profile
and cross-section of the upstream and downstream channel reaches of
the development under consideration.
(4) A development grading plan prepared to suitable contour intervals
with grading details to indicate proposed street grades and elevations,
building site elevations and surface elevations at critical points
throughout the development (similar to the F.H.A. type grading plan).
In order to ensure the proper performance of the work to be completed under plans as approved under §
143-16 above, the Town may require a cash deposit or a performance bond issued by an acceptable bonding or surety company.
The approval of plans for proposed drainage systems and flood
hazard prevention requirements shall not constitute a representation,
guaranty or warranty of any kind or nature by the Town of Lewiston
or by an officer or employee thereof of the safety, operation, adequacy
or intent of the proposed facilities, and shall create no liability
upon or cause for action against such public body, officer or employee
for any damage that may result from construction pursuant thereto.
The provisions of §§
143-10 through
143-18 hereof are intended to apply primarily to runoff of natural waters in subdivisions and other developments of land use occurring after the enactment of this article and are not intended to repeal or amend the provisions of Local Law No. 8-1966, being Chapter
340 of the Code of the Town of Lewiston, except to the extent that the provisions of this article are inconsistent therewith, in which case the provisions hereof shall govern.
Before issuing any building permit within the Town of Lewiston,
the Building Inspector shall review the application to determine whether
the site is located within any flood hazard area or is reasonably
safe from flooding. If he shall find that the site is subject to flood
hazard, he shall require that the construction be designed and anchored
as to prevent flotation, collapse or lateral movement, that the construction
materials used and the method of construction are resistant to flood
damage, and that adequate drainage is provided to reduce exposure
to flood hazards.