Current through Register Vol. 39, No. 6, September 16, 2024
(a) This Rule shall apply only to a dam
operated by a small power producer, as defined in
G.S.
62-3(27a), that diverts
water from 4,000 feet or less of the natural stream bed. The length of the
bypassed reach shall be measured from the toe of the dam to the point where the
diverted water re-enters the natural channel, following the centerline of the
natural channel.
(b) The minimum
release for a hydroelectric project subject to this Rule shall be determined
according to the procedures described in Subparagraphs (1)-(5) of this
Paragraph. If at any time the inflow just upstream of the dam is less than the
minimum flow required in the bypassed reach, then the minimum flow may be
reduced to a level equal to this inflow.
(1)
If the aquatic habitat in the bypassed reach is rated poor, then the minimum
release to the bypassed reach shall be determined as follows:
(A) If the 7Q10 is less than or equal to 10
percent of the mean annual daily flow, then the minimum release to the bypassed
reach shall be the 7Q10 flow.
(B)
If the 7Q10 is greater than 10 percent of the mean annual daily flow, and there
are no existing point source discharges of wastewater to the bypassed reach,
then the minimum release to the bypassed reach shall be 0.8 times the
7Q10.
(C) If the 7Q10 is greater
than 10 percent of the mean annual daily flow, and one or more existing point
source discharges of wastewater enter the bypassed reach, then the minimum
release to the bypassed reach shall be the 7Q10 flow.
(2) If the bypassed reach does not have an
aquatic habitat rating of "poor," is not on a special case stream, and is
located in the piedmont region, as defined in Rule .0501(h) of this Section,
then the minimum release to the bypassed reach shall be determined as follows:
(A) If the 7Q10 is less than or equal to six
percent of the mean annual daily flow, then the minimum release to the bypassed
reach shall be 3.0 times the 7Q10 flow.
(B) If the 7Q10 is greater than six percent
of the mean annual daily flow, and less than or equal to 10 percent of the mean
annual daily flow, then the minimum release to the bypassed reach shall be 2.2
times the 7Q10 flow.
(C) If the
7Q10 is greater than 10 percent of the mean annual daily flow, then the minimum
release to the bypassed reach shall be 1.2 times the 7Q10 flow.
(3) The minimum flow determined by
the procedures described in Subparagraphs (1) and (2) of this Paragraph may be
adjusted downward by the Department if that adjustment would not result in
significant loss of aquatic habitat. This adjustment may be based on factors
including:
(A) the type of aquatic habitat
present in the bypassed reach;
(B)
the length of the bypassed reach.
(4) If the applicant or owner disputes the
minimum flow determined by the procedures described in Subparagraphs (1) and
(2) of this Paragraph, he may undertake a site-specific field study, as defined
in Rule .0501(j) of this Section, subject to the review and approval of the
Department. The final minimum release required will not exceed the amount
determined by the procedures described in this Section.
(5) The minimum flow for a dam on a special
case stream, or on a stream located in the mountain region, as defined in Rule
.0501(h) of this Section, which does not exhibit poor aquatic habitat; shall be
determined by a site-specific instream flow study, as defined in Rule .0501(j)
of this Section. This study shall be conducted by the applicant or his
consultants, and shall be subject to approval by the Department.
(c) A dam operated by a small
power producer, as defined in
G.S.
62-3(27a), which was
operating to produce power as of October 13, 1994, and which is not under the
jurisdiction of the Federal Energy Regulatory Commission, shall not be required
by this Rule to increase its minimum flow above the amount required on October
13, 1994.
Authority
G.S.
143-215.24;
143-215.25;
143-215.31;
143-215.32;
143-215.33;
143-215.36;
Eff.
December 1, 1994;
Amended Eff. April 1, 1995;
Pursuant
to G.S.
150B-21.3A, rule is necessary without
substantive public interest Eff. December 23,
2017.
