WPTA 2008-001, Stream Crossings




Public Hearing to amend the Water Protection Ordinance to allow stream crossings meeting specific requirements and revise the mitigation plan requirements




Messrs. Tucker, Foley, Davis, Kamptner, Graham, and Brooks, and Ms. Ambler







May 7, 2008


ACTION:     X          INFORMATION:   



  ACTION:              INFORMATION:   











The purpose of this public hearing is to consider amending the Water Protection Ordinance (WPO) by making certain stream crossings that meet specific requirements an allowed use and revising the requirements when other stream crossings may be allowed by the program authority with a mitigation plan.  On March 12, 2008, the Board was presented three options for the treatment of stream crossings of protected stream buffers in the WPO (see Attachment A).  After consideration, the Board directed staff to proceed with developing an ordinance amendment that permits stream crossings where necessary for the lot to be used and developed as permitted in the underlying zoning district and under the applicable regulations of the Subdivision Ordinance.  These stream crossings would be allowed provided that specific requirements have been met.    




Goal 2: Protect the County’s Natural Resources




The proposed text amendment is provided as Attachment B. In addition to the allowed stream crossings, staff is recommending changes that would give the program authority the discretion to allow other stream crossings with a mitigation plan, and that clarify and strengthen the procedural and substantive requirements for mitigation plans.  A discussion of the proposed amendments to sections 17-320, 17-321 and 17-322 follows.


17-320 Allowed Uses:

The proposed amendments to section 17-320 would allow a stream crossing of an intermittent or perennial stream, provided that specific requirements have been met.  The following requirements focus on assuring the stream crossing will not result in excessive stream erosion: 1) proper sizing and installation of the structures for perennial streams (the crossing structures must allow the streambed and streambanks to retain a natural cross-section, a requirement that is consistent with typical State and Federal permit requirements); 2) stabilization measures to assure the stream is restored; 3) keeping the stream disturbance to the minimum necessary for the use; 4) restoration of the disturbed area as soon as reasonably possible; 5) mitigation for the disturbed area through vegetated buffers where possible; 6) the limitation to a single stream crossing under this section; and 7) notification by the owner of any State or Federal permit conditions associated with the crossing prior to County approval. The last requirement provides the program authority the opportunity to review State or Federal approval conditions and to verify that the County is not approving anything contrary to those permit conditions.      


17-321 Types of development allowed in the stream buffer:

Recognizing that a property owner may desire a stream crossing that cannot satisfy all of the requirements of section 17-320, the proposed amendments to section 17-321 would provide the program authority the discretion to permit other stream crossings, including crossings in addition to those allowed by section 17-320, with an approved mitigation plan. 


If an additional stream crossing is sought, the owner must also demonstrate to the program authority that the environmental impacts from the entire road, street or driveway necessitated at a single stream crossing would be greater than the environmental impacts caused by an additional crossing and its associated road, street or driveway if the additional crossing was not allowed.  The relevant environmental impacts to be considered are delineated in the ordinance (Sec. 17-321(4)).


17-322     Mitigation plans if development allowed in stream buffer:

The proposed amendments to section 17-322 would require that mitigation plans for a road, street or driveway encroaching into or crossing a stream buffer be submitted and reviewed with the subdivision plat, site plan or building permit (Sec. 17-322(A)).  This requirement would assure that a building permit dependent upon a stream crossing would not be approved before the mitigation plan has been approved.  In addition, the proposed amendments would authorize the program authority to require design changes to assure that the development meets the purposes of the Water Protection Ordinance and to require ongoing maintenance of the mitigation measures (Sec. 17-322(C)(2) and (C)(3)).  Also, if the owner proposed more than a single stream crossing for a road, street or driveway, the proposed amendments would require that the owner demonstrate that environmental impacts resulting from a single crossing would be greater than those if the additional crossing was allowed (Sec. 17-322(C)(6)) as discussed above.  Finally, the proposed amendments would add criteria for evaluating a mitigation plan (Sec. 17-322(D)(4) and (D)(5)).




No additional impact to the County budget is anticipated.  Allowed stream crossings can be routinely administered as part of permit applications.  For those circumstances that might require a mitigation plan, fees are anticipated to cover the cost of the plan review and inspections.        




Staff recommends approval of WPTA 2008-001, as set forth in Attachment B.    




A - March 12, 2008 Executive Summary: Water Protection Ordinance – Stream Crossings

B – Water Protection Text Amendment

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