12 C20-2023-030 - Airole Way Site Specific SOS Amendment Presentation.pdf — original pdf

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1905 & 1908 Airole Way Site-Specific SOS Amendment C20-2023-022 Leslie Lilly Environmental Program Coordinator Watershed Protection C I T Y O F A U S T I N W A T E R S H E D P R O T E C T I O N D E P A R T M E N T 1 of 8SOS Amendment • 1 9 9 2 S a ve O u r S p r i n g s ( S O S ) o r d i n a n c e a d o p t e d by c i t i ze n i n i t i a t i ve Pe r 2 5 - 8 - 5 1 5 , va r i a n c e s t o S O S a r e n o t a l l ow e d • S u p e r m a j o r i t y o f C o u n c i l m u s t a p p rove a m e n d m e n t s t o S O S • C o u n c i l Re s o l u t i o n # 2 0 2 3 0 9 1 4 - 0 7 9 o n S e p t e m b e r 1 4 t h, 2 0 2 3 : • “ C o u n c i l i n i t i a t e s s i t e s p e c i f i c v a r i a n c e s a n d a m e n d m e n t s t o t h e L a n d 2 7 D e v e l o p m e n t C o d e, i n c l u d i n g s i t e - s p e c i f i c a m e n d m e n t s t o C i t y C o d e C h a p t e r 2 5 - 2 8 8 , S u b c h a p t e r A , A r t i c l e 1 3 ( S a v e O u r S p r i n g s I n i t i a t i v e ) , a s m i n i m a l l y r e q u i r e d t o 2 9 a l l o w f o r p r o p o s e d d e v e l o p m e n t o f t h e l o t s l o c a t e d a t 1 9 0 5 a n d 1 9 0 8 A i r o l e Wa y.” C I T Y O F A U S T I N W A T E R S H E D P R O T E C T I O N D E P A R T M E N T 2 of 8C 2 0 - 2 0 2 3 - 0 3 0 C I T Y O F A U S T I N W A T E R S H E D P R O T E C T I O N D E P A R T M E N T 3 of 8Site Features • Barton Creek Watershed • Barton Springs Zone • Edward Aquifer Recharge • Not in the Critical Water Quality Zone (CWQZ) and Water Quality Transition Zone (WQTZ) • No Critical Environmental Features (CEF) • Combined area 0.55 acres • Existing Impervious Cover 0.0614 acres or 2,675 sqft C I T Y O F A U S T I N W A T E R S H E D P R O T E C T I O N D E P A R T M E N T 4 of 8SOS Amendment • SOS requirement for impervious cover limited to 15% Net Site Area (NSA) (0.0539 acres or 2348 sqft) • Proposed impervious cover 32.9% Gross Site Area (GSA) (0.1818 acres or 7920 sqft) C I T Y O F A U S T I N W A T E R S H E D P R O T E C T I O N D E P A R T M E N T 5 of 8SOS Amendment • SOS requirement for non- degradation water quality treatment • Proposed water quality controls that will capture the first ½” of runoff from 4,651 sqft of roof area from both lots combined with infiltration area of 2,250 sqft C I T Y O F A U S T I N W A T E R S H E D P R O T E C T I O N D E P A R T M E N T 6 of 8Staff Recommendation Staff recommends approval of the proposed site-specific SOS amendments with the following conditions: Limit impervious cover to 32.9% GSA • • Require water quality treatment of 4,651 sqft of roof area from both lots combined with on-site controls capturing the first ½” of runoff, irrigated within 120 hrs to an infiltration area of 2250 sqft and designed and maintained to Environmental Criteria Manual requirements. • Utilize native plants and trees in landscaping C I T Y O F A U S T I N W A T E R S H E D P R O T E C T I O N D E P A R T M E N T 7 of 8Questions? C o n t a c t I n f o r m a t i o n : L e s l i e L i l l y ( W P D ) l e s l i e . l i l l y @ a u s t i n t e x a s . g o v C I T Y O F A U S T I N W A T E R S H E D P R O T E C T I O N D E P A R T M E N T 8 of 8