Proposed Drainage Policy Changes PROPOSED DRAINAGE POLICY CHANGES

Proposed Drainage Policy Changes

PROPOSED DRAINAGE POLICY CHANGES Why are we proposing changes? • Addressing and preventing drainage issues are a community priority • Implementing recommendation from our Drainage Area Master Plan • Improve our Community Rating System (CRS) Classification • General housekeeping items

PROPOSED DRAINAGE POLICY CHANGES Drainage Area Masterplan Recommendations • Comprehensive and sustainable watershed program plan • Multiyear workplan complete • Phase I (policy changes) underway • Required to align with the State Flood Plan • Hydrology updates for current State standard (Atlas 14) • Improvements and changes to floodplain management • Floodplain Administrator to be PE & CFM • Improve FEMA CRS • Improving standards and providing clarity

PROPOSED DRAINAGE POLICY CHANGES Community Rating System (CRS) Recommendations for Improved Rating • CRS provide reduction in flood insurance with higher standards • Investigate potential to achieve improved rating to obtain better benefits for residents • Previous evaluation led to a loss of rating (from a 6 to an 8)

PROPOSED DRAINAGE POLICY CHANGES Drainage & Erosion Control Design Manual

PROPOSED DRAINAGE POLICY CHANGES Chapter 2 - Drainage Policy and Criteria • Add Floodplain Development Requirements • Regulate to the 1% Annual Chance Ultimate Development Flood • Potential CRS 440 points • Add Compensatory – Excavation for floodplain • Potential CRS 130 points

PROPOSED DRAINAGE POLICY CHANGES Chapter 2 - Drainage Policy and Criteria • Update Stream Buffers Requirements Contributing Drainage Area Waterway Classification Set Back Distance from Stream Centerline 64 to 128 acres Peripheral Waterway 50 -feet 128 to 320 acres Minor Waterway 100 -feet 320 to 640 acres Intermediate Waterway 200 -feet > 640 acres Major Waterway 300 -feet

PROPOSED DRAINAGE POLICY CHANGES Chapter 3 – Design Rainfall - *consent item § Update hydrology data to NOAA Atlas 14, Vol Hotel Occupancy Tax Collections $ 4 500 000 $ 4 010 000 $ 4 000 11 Texas statewide precipitation study $3, 996, 000 $3, 400, 000 $ 3 500 000 § New 100 -year (1% AC) 24 -hour rainfall depth $ 3 000 $ 2 428 000 $ 2 500 000 for City of New Braunfels is 13. 1 inches. § Previous 12. 30 inches. $ 2 000 $ 1 500 000 § Currently required for all floodplain permits $ 1 000 $ 500 000 and city capital improvement projects $FY 2018 FY 2019 FY 2020 Estimate FY 2021 Budget § Effective date January 1, 2021

PROPOSED DRAINAGE POLICY CHANGES Chapter 4 – Determination of Design Discharge • Update references for Atlas 14 • Include mitigation for the 50 -year design frequency • Potential CRS 190 points

PROPOSED DRAINAGE POLICY CHANGES Chapter 10 – Detention and Retention Facilities • Update maximum water depths • Update mitigation for 2, 10, 25, 50, and 100 -year peak runoff • Update structure design to include the 50 -year

PROPOSED DRAINAGE POLICY CHANGES Floodplain Ordinance

PROPOSED DRAINAGE POLICY CHANGES Floodplain Regulations – Code Sec. 58 • Sec. 58 -27 – Definitions • Sec. 58 -28 – General provisions • Sec. 58 -29 – Administration • Sec. 58 -30 – Provisions for flood hazard reduction

PROPOSED DRAINAGE POLICY CHANGES Key Floodplain Regulations Changes • Regulatory floodplain established at 1% Annual Chance Ultimate Development • Designate floodplain administrator as the City Engineer • Variance procedures through City Council • Reference to Drainage and Erosion Control Manual • Clarify “no-rise/no-impact” study requirements

PROPOSED DRAINAGE POLICY CHANGES CRS Improvement

PROPOSED DRAINAGE POLICY CHANGES Other needs to improve CRS • Improve elevation certificates • Prerequisite • Outreach projects and Public Protection Information Committee • 130 points • Create a flood information webpage • 262 points • Update floodplain studies • 110 points • Maintain 5/5 Building Code Effective Grading Schedule • Class 6 Prerequisite

PROPOSED DRAINAGE POLICY CHANGES Summary

PROPOSED DRAINAGE POLICY CHANGES CRS Points Comparison 2017 CREDIT 1279 Points POTENTIAL CREDIT WITH CHANGES 2500+ Points

PROPOSED DRAINAGE POLICY CHANGES Next Steps üOctober 29, 2020 – WAC presentation* üNovember 4, 2020 – Planning Commission presentation* • November 23, 2020 – City Council presentation* • Winter 2020/2021 – Stakeholder and community input • Spring 2021 – WAC, Planning Commission, City Council – Action • Summer 2021 – Submit for CRS Modification * Recommended approval of changes to Chapter 3 (Consent Item 3 H)

QUESTIONS?