Current through Register Vol. 44, No. 14, April 6, 2022
purpose of the water well yield test is to provide evidence that a water well
will produce a sustainable flow rate for an extended period of time and to
quantify that flow rate. Before being put into use, new and redeveloped wells
shall be tested for well yield. The yield test for water well flow rates shall
meet the following performance requirements:
(1) water well yield tests shall be performed
for a period of time adequate to quantify well yield.
(2) water level and flow rate observations
shall be made and recorded, at a minimum, before the start of the yield test,
immediately upon the cessation of water withdrawal, and periodically during
drawdown, and recovery periods. Frequency of measurements shall be made as
necessary for the test method.
water discharged during a yield test shall be discharged in a manner that
avoids short circuiting of the water back into the aquifer.
(4) for wells that have been subjected to
hydrofracturing the yield test shall not commence until redevelopment has been
completed and, as a minimum, until the volume of water pumped/discharged into
the aquifer has been removed from the well.
(5) the well yield determined for new wells
shall be recorded on the Well Completion Report form submitted for that well to
the New York State Department of Environmental Conservation. Data generated
during the yield test shall be provided to the owner of the well, and provided
upon request to the State or local agency(ies) having jurisdiction.
(b) The standard well yield test
(1) A minimum four-hour period
of stabilized drawdown while pumping at a constant flow rate.
(2) During the period of stabilized drawdown
the stabilized water level shall not fluctuate more than plus or minus 0.5 foot
(i.e., within a vertical tolerance of one foot) for each 100 feet of water in
the well (i.e., initial water level to bottom of well) over the duration of
constant flow rate of pumping. Water level measurement may be determined by
steel tape, calibrated pressure gauge attached to an air line terminating at
least five feet above the pump intake, electric sounder, or pressure
(3) The recovery period
shall include observation of the water level in the well after cessation of
pumping from the drawdown level back to at least 90 percent of the initial
water level or for a period of 24 hours, whichever occurs first. If the water
level does not recover to 90 percent after 24 hours, the tested flow rate may
not be sustainable for an extended period of time.
(c) The well yield test requirements set
forth in subdivision 5-B.4(b) may be modified, or an alternative yield test
that meets the minimum performance requirements forth in subdivision 5-B.4(a)
may be used as follows:
(1) where the local
health department having jurisdiction has determine that adequate hydrogeologic
information and uniform conditions exist; or
(2) when an experienced hydrogeologist or
licensed professional engineer directs and certifies the test; or
(3) for facilities planned for well water use
of less than 500 gallons per day, pumping, bailing or air lift test methods may
(4) the well yield of a
flowing artesian well may be determined by direct flow measurement if the
artesian flow rate equals or exceeds the desired water use rate.
N.Y. Comp. Codes R.
& Regs. Tit. 10app 5-B §