requirements contracts for engineering design and related services ...

a) General description of all sewers located within the project area;
b) Maps of all existing drainage plans;
c) Maps of existing sewer easements;
d) Maps/sketches of all proposed sewer projects;
e) A discussion of all topographic feature;
f) Proposed mapping or demappings;
g) Outfall locations;
h) Encroachments upon sewer easements, etc.
C. DRAINAGE AND GRADE STUDY, AND DRAINAGE PLAN
1. This study shall provide for:
a) The retention of as many of the existing grades and as many of the existing street systems as possible, provided
the procedures, concepts and criteria used in the design of these grades and street systems are in accordance with
the design parameters of the Department, and of the Bureau of Sewers.
b) The retention of as much of the existing sanitary and storm water sewer systems(s) as possible, provided the
sewers meet the present design criteria of the Bureau of Sewers. The Consultant must consider the age, condition
and capacity of the existing sewer system in preparing the proposed drainage plans(s). In order to evaluate all the
factors relating to this decision, the Consultant will be required to consult with the various Divisions of the Department
of Environmental Protection that may have knowledge of the conditions affecting the sewers.
2. In evaluating the feasibility of revising existing drainage plan(s), the Consultant shall endeavor to accommodate the
recommended changes within the mapped street widths and easements, and legal grade lines of the streets. In instances
where such accommodation proves impractical, the Consultant shall judiciously modify street design proposals to enable
the Consultant to produce a workable drainage plan.
3. Prior to commencing the design of the proposed drainage plan, the Consultant shall consult with the Drainage Section
of the Department of Environmental Protection on the retention of the existing sewer and the proposing of sewers that
slope contrary to the slope of the street, as determined from the final mapped grade.
4. The Consultant is advised that there may be other projects under current or future contracts between other
consultants and the Department that should be considered in the design of this project.
5. When designing the sanitary and storm water sewers for this project, the tributary flow from adjacent areas, outside
the limits of this project, must be included.
6. Previously completed drainage plans that affect the project area must also be considered.
7. With respect to sanitary sewer schemes, the Consultant shall be required to utilize all existing area interceptor sewers
for sanitary sewer drainage.
8. The Design of all Sanitary and Storm Water Sewers shown on the proposed drainage plans shall:
a) Be based upon approved adopted final maps where available, and/or proposed grades and street systems,
or upon otherwise available topographic maps of the area and corresponding final and/or proposed grades.
b) Be related to the prevailing zoning regulations, land occupancy and estimated future population with due
allowance for practical ultimate need when the areas are fully built up.
c) Be related to the probable extent of pervious and impervious surface cover when the areas are fully
developed. Underdeveloped residential, industrial, or commercial areas, parks, Government reservations, and
institutional land shall be treated on an area basis only.
d) Be in conformity with current practices, requirements and design criteria of the Bureau of Water and Sewer
Operations.
NYC Department of Design and Construction
Infrastructure, October 2012
GR-43