City of Abilene Master Drainage Plan City Council

City of Abilene Master Drainage Plan City Council Presentation October 25, 2018 Abilene Master Drainage Plan – City Council – October 25, 2018 1

What Flooding Costs Abilene § Property Damage • • Residential Commercial Contents Damage § $18 M average annually § Vehicle Damage § Potential Loss of Life § • • • Residents Visitors First Responders Channel Erosion § Water Quality § Buttonwillow Creek during July 2015 Flood 2 Abilene Master Drainage Plan – City Council – October 25, 2018

Current Status City has an effective channel maintenance program § Only General Obligation bond funding for capital projects § Increase in stormwater utility fee in 2016 generates $350, 000 § Initiated Master Drainage Plan to: § 1. 2. § Develop an updated list of drainage projects Lay out Road Map Series of Storm Water Stakeholder meetings 3 Abilene Master Drainage Plan – City Council – October 25, 2018

Storm Water Stakeholders Committee 4 Abilene Master Drainage Plan – City Council – October 25, 2018

Master Drainage Plan Process Review Existing Data Stakeholde rs Meeting #1 Creek Visit Stakeholde rs Meeting #3 CIP for Top 10 Problem Areas City Staff Workshop Draft 20 Problem Areas Stakeholde rs Meeting #2 Identified 46 Problem Areas Site Reconnaissan ce Final 20 Problem Areas CIP for Top 8 Problem Areas Scored 20 Problem Areas Meeting with FW USACE Draft Road Map City Council Presentatio n Project Specific Criteria Financial Analysis Abilene Master Drainage Plan – City Council – October 25, 2018 5

All Problem Areas § 46 Locations • • § 10 Stakeholder 3 FIS Profiles 3 City Staff 30 Creek Visits Watersheds • • 9 Elm Creek 15 Catclaw Creek 5 Little Elm Creek 13 Cedar Creek 2 Rainey Creek 1 Lytle Creek 1 Elm & Cedar 6 Abilene Master Drainage Plan – City Council – October 25, 2018

Top 20 Problem Areas § Watersheds • • • 2 8 3 6 1 Elm Creek Catclaw Creek Little Elm Creek Cedar Creek Elm & Cedar 7 Abilene Master Drainage Plan – City Council – October 25, 2018

Problem Area Ranking Criteria Structural Flooding Roadway Inundation Repetitive Losses 8 Abilene Master Drainage Plan – City Council – October 25, 2018

Top 10 Problem Areas 9 Abilene Master Drainage Plan – City Council – October 25, 2018

Refinement of CIP Solutions § Input from City Council Workshop in November 2017 • Elm Creek Diversion Channel (not the Detention Pond #2) • $80 million total project ($20 million local match, mostly ROW) • Next step is preliminary investigation to determine boundaries • Position for FEMA grant funding (HMGP or PDM) » Letter from USACE to confirm not interested in moving forward » Calculate B/C ratio using FEMA’s BCA Tool • Downtown Railroad Underpasses is a lower priority • Lowered from priority #3 to #8 • Investigate closer outfall for Treadaway / S 27 th Street • Outfall is concrete lined ditch along north side of S 27 th Street • Minimize additional property acquisition • Elm Creek Diversion Channel corridor • Detention on Little Elm Creek and Buttonwillow Creek Abilene Master Drainage Plan – City Council – October 25, 2018 10

Road Map to Reduce Flood Risk Little Elm at S 7 th St ek e r C on m l E ersi l Div anne Ch Reduced Flood Risk act p r Im he g i H Lake Abilene Operations ac p r Im we Lo Current Conditions Catclaw at S 11 th / S 7 th Buttonwillow Crossings t Treadaway at S 27 th St Downtown Railroad Underpasses Curry Lane Detention Pond Buttonwillow Detention Elm Detention at Southwest Dr Abilene Master Drainage Plan – City Council – October 25, 2018 11

Summary of CIP Solutions 12 Abilene Master Drainage Plan – City Council – October 25, 2018

Sequencing of CIP Solutions § Additional phasing & prioritization of Top 10 CIP projects • § Based on project specific details Project Specific Criteria: Calculated a score for each project phase § Sequenced CIP phases based on § • • Highest total point score Completion of previous project phases Abilene Master Drainage Plan – City Council – October 25, 2018 13

Projects on Higher Impact Road 14 Abilene Master Drainage Plan – City Council – October 25, 2018

Projects on Lower Impact Road 15 Abilene Master Drainage Plan – City Council – October 25, 2018

Projects on Lower Impact Road 16 Abilene Master Drainage Plan – City Council – October 25, 2018

Financial Analysis § Developed Financial Model for Stormwater Fund • Forecasts revenues and expenditures out to 2048 • Assumes 2% inflation on personnel / maintenance / supplies • Annual input of • Residential & Commercial Rates • Customer Count (growth) • Collections Rates • Sequential implementation of CIP program • Assumes 3% inflation • Cash as you go • Bond financing (> $1 million) • 4. 5% with 3. 5% soft costs • Tool for City staff to update and maintain going forward 17 Abilene Master Drainage Plan – City Council – October 25, 2018

Duration of Road Map Journey § § Evaluated rates required for 3 Scenarios: • Scenario 1 = Complete CIP projects in 10 years • Scenario 2 = Complete CIP projects in 20 years • Scenario 3 = Complete CIP projects in 30 years Because City currently has limited stormwater CIP funds, all 3 Scenarios require stormwater rate increases 18 Abilene Master Drainage Plan – City Council – October 25, 2018

Scenario 1 – Complete CIP in 10 Years § Projects identified in CIP are completed by 2028 § 20% rate increase in 2019, 16% to 10% rate increases needed in other years Abilene Master Drainage Plan – City Council – October 25, 2018 19

Scenario 1 – Complete CIP in 10 Years § Example: Tier 3 Residential Customer • Total bill increase of 219% (or $7. 13 / month) by 2028 $10. 07 $3. 25 20 Abilene Master Drainage Plan – City Council – October 25, 2018

Scenario 1 – Complete CIP in 10 Years § Total revenue requirement of $7. 984 million in 2028 21 Abilene Master Drainage Plan – City Council – October 25, 2018

Scenario 1 – Complete CIP in 10 Years § 2 to 5 project phases per year, completed in 2028 * Blue highlight indicates debt funded project phases Abilene Master Drainage Plan – City Council – October 25, 2018 22

Scenario 2 – Complete CIP in 20 Years § Projects identified in CIP are completed by 2038 § 15% rate increase in 2019, 10% to 5% rate increases needed in other years Abilene Master Drainage Plan – City Council – October 25, 2018 23

Scenario 2 – Complete CIP in 20 Years § Example: Tier 3 Residential Customer • Total bill increase of 95% (or $2. 94 / month) by 2028 $6. 19 $3. 25 24 Abilene Master Drainage Plan – City Council – October 25, 2018

Scenario 2 – Complete CIP in 20 Years § Total revenue requirement of $5. 442 million in 2028 25 Abilene Master Drainage Plan – City Council – October 25, 2018

Scenario 2 – Complete CIP in 20 Years § 2 project phases per year, completed in 2038 * Blue highlight indicates debt funded project phases Abilene Master Drainage Plan – City Council – October 25, 2018 26

Scenario 3 – Complete CIP in 30 Years § Projects identified in CIP are completed by 2048 § 10% rate increase in 2019, 3% to 2% rate increases needed in other years 27 Abilene Master Drainage Plan – City Council – October 25, 2018

Scenario 3 – Complete CIP in 30 Years § Example: Tier 3 Residential Customer • Total bill increase of 39% (or $1. 28 / month) by 2028 $4. 53 $3. 25 28 Abilene Master Drainage Plan – City Council – October 25, 2018

Scenario 3 – Complete CIP in 30 Years § Total revenue requirement of $3. 593 million in 2028 29 Abilene Master Drainage Plan – City Council – October 25, 2018

Scenario 3 – Complete CIP in 30 Years § 1 or 2 project phases per year, completed in 2048 * Blue highlight indicates debt funded project phases Abilene Master Drainage Plan – City Council – October 25, 2018 30

Stormwater Utility Rates - Residential 10 Year = $10. 07 20 Year = $6. 19 30 Year = $4. 53 Current 31 Abilene Master Drainage Plan – City Council – October 25, 2018

Stormwater Utility Rates - Residential 10 Year = $10. 07 20 Year = $6. 19 30 Year = $4. 53 Current 32 Abilene Master Drainage Plan – City Council – October 25, 2018

Next Steps Receive City Council input on 3 Scenarios § Finalize Draft Report § City Council Adoption § Questions / Discussion 33 Abilene Master Drainage Plan – City Council – October 25, 2018