§ 25-8-364. FLOODPLAIN MODIFICATION.

(A)

Floodplain modification within a critical water quality zone is prohibited except as allowed under Section 25-8-261 ( Critical Water Quality Zone Development ).

(B)

Floodplain modification outside a critical water quality zone is allowed only if the modification proposed:

(1)

is necessary to protect public health and safety by addressing an existing threat, as determined by the director of the Watershed Protection Department;

(2)

would provide a significant, demonstrable environmental benefit, as determined by a functional assessment of floodplain health as prescribed by the Environmental Criteria Manual;

(3)

is located within a floodplain area classified as in fair or poor condition, as determined by a functional assessment of floodplain health, prescribed by the Environmental Criteria Manual; or

(4)

is necessary for development allowed under Section 25-8-261 ( Critical Water Quality Development ) or 25-8-262 ( Critical Water Quality Zone Street Crossings ).

(C)

All floodplain modifications must:

(1)

be designed to accommodate existing and fully-vegetated conditions;

(2)

encourage sound engineering and ecological practices, prevent and reduce degradation of water quality, and encourage the stability and integrity of floodplains and waterways, as prescribed in the floodplain modification criteria in the Environmental Criteria Manual;

(3)

restore floodplain health, or provide mitigation if restoration is infeasible, to support natural functions and processes as prescribed in the floodplain modification criteria in the Environmental Criteria Manual; and

(4)

comply with the requirements of Chapter 25-7 ( Drainage ), the Drainage Criteria Manual, and the Environmental Criteria Manual.

(D)

If mitigation is required under this Section, it may be satisfied by:

(1)

paying into the Riparian Zone Mitigation Fund a nonrefundable amount established by ordinance;

(2)

transferring in fee simple or placing restrictions on mitigation land approved by the director of the Watershed Protection Department and meeting the following conditions:

(a)

located within the same watershed classification;

(b)

in accordance with the procedures in Section 25-8-26 ( Redevelopment Exception in the Barton Springs Zone ), Subsection (H) (3);

(c)

dedicated to or restricted for the benefit of the City or another entity approved by the Watershed Protection Department director and which the City or other approved entity accepts;

(d)

an amount proportionate to the amount of area within the existing floodplain that is proposed to be modified, as prescribed in the Environmental Criteria Manual; or

(3)

a combination of the mitigation methods described in Subparagraphs (1) and (2), if approved by the director of the Watershed Protection Department.

Source: Ord. 20131017-046; Ord. No. 20160922-048 , Pt. 6, 10-3-16; Ord. No. 20170615-102 , Pt. 23, 6-15-17.