Water Quality Protection Zones Kathryn L. Walker City of Norman City Attorney’s Office

Storm Water Master Plan Began in 2007 after citizen-led development of a scope of work and RFP process Identified Goals Reduce flooding dangers Protect water quality Enhance the environment Advance recreational opportunities (studied separately through the Greenway Master Plan)

Storm Water Master Plan – Methodology Analyzed 36 watersheds – problem areas received more detailed study Hydrologic analyses performed for 307 square miles of drainage area Hydraulic analyses and floodplain mapping developed for almost 400 stream miles (59 miles of detailed stream analysis and 333 miles of approximate stream analysis)

Storm Water Master Plan – Key Points Focus on stream flooding, stream erosion, water quality and local drainage Although existing conditions were reviewed, the identification and evaluation of flooding along major streams focused on future build-out watershed conditions (Norman 2025 land use plan)

Storm Water Master Plan Water Quality - Key Issues Utilizing structural and non-structural water quality controls in new developments including low impact development techniques Providing enhanced maintenance of creeks and storm water detention facilities in existing and new developments Incorporating regulatory floodplain or “Stream Planning Corridors” dedications in new developments Area inundated by the 100 year flood assuming full build-out conditions in those areas with 40 or more acres of drainage area

Sources of Information Publications and Model Ordinances EPA Model Ordinance to Protect Local Resources Protecting Stream & River Corridors, UGA Buffer Protection & Management Ordinance, Baltimore, MD Vegetated Riparian Buffers & Buffer Ordinance, State of South Carolina Ordinances in Other Cities Lenexa, KS San Antonio, TX Austin, TX Overland Park, KS Kansas City, MO Tulsa, OK (regulatory floodplain)

WQPZ – Process for Adoption Public Meeting to review regional approaches and how they would apply in Norman – Dec. 2009 Internal drafting – 1 year Meetings of SW Task Force – 5 + months Planning Commission recommendation – June 2011 City Council adoption – June 2011

WQPZ Regulations - Structure Part of Norman’s subdivision regulations Limited to new applications for Preliminary Plats and Norman Rural Certificates of Survey for developments in the Lake Thunderbird watershed A WQPZ would be designated along each stream to serve as a natural vegetative buffer on new or expired (and not grandfathered in ) plats and certificates of survey

What is a WQPZ? A vegetated strip of land that lies along a Stream or Lake Thunderbird and its adjacent wetlands, floodplains or slopes that is comprised of the stream bed and areas adjacent to the stream bed

WQPZ – How big is it? Base width – the greater of 100 feet in width, measured from top of bank, on each side of the stream; or Designated full build-out floodplain; or Designated FEMA floodplain

WQPZ Base Width – When it Decreases Water quality targets must be met thru approved engineered process (using Wichita/Sedgwick County Stormwater Manual) Phosphorus – 58% removal Nitrogen – 75% removal Must document protection against flooding and bank erosion anticipated from the 1% flood assuming full-buildout in those areas with 40 or more acres of drainage area Base width reduced to 25 feet

WQPZ Base Width – When It Increases Slope of a 25 feet segment is over 20% (increase by 25 feet) Stream is a 2nd order stream with continuous water (increase by 25 feet) Stream is 3rd order and higher (increase by 25 feet)

Significance of WQPZ Designated on plat No structures or septic systems in the zone except structural controls or other enhancing design features Protective covenants required to limit activity in the WQPZ in perpetuity

Other Features Allows for modification of Norman’s current Engineering Design Criteria to accommodate Low Impact Development strategies Drainage easement required to be granted to City for area flooded in a 1% rainfall event Buffer averaging allowed to accommodate unusual development patterns, shallow lots, stream crossings or storm water ponds

Questions?