CALDWELL COUNTY REGIONAL WATER AND WASTEWATER PLANNING STUDY Prepared for GUADALUPE-BLANCO RIVER AUTHORITY January 2010 C O N S U L T I N G E N G I N E E R S 7 5 5 0 I H 1 0 W E S T , S U I T E 3 0 0 S A N A N T O N I O , T E X A S 7 8 2 2 9 T e x a s P . E . F i r m R e g i s t r a t i o n N o . F - 9 2 9 P r o j e c t N o . 0 9 7 2 . 0 0 0 . 0 0 0 C O N S U L T I N G E N G I N E E R S TABLE OF CONTENTS Page EXECUTIVE SUMMARY ………………………………………………… ES-1 SECTION 1 INTRODUCTION 1.1 Background ………………………………………………..… 1-1 1.2 Purpose and Scope ……….……….……………………….… 1-3 1.3 Project Task ……..………………………………………….. 1-4 1.4 Participants and Sponsors ……………………………………... 1-5 SECTION 2 CALDWELL COUNTY CHARACTERISTICS 2.1 City Limits and ETJ Boundaries ………….………………..… 2-1 2.2 Land Use …..……………………………………………….… 2-3 2.3 Watersheds ……….…………………………………………… 2-3 2.4 Certificates of Convenience and Necessity (CCN) …………… 2-7 2.4.1 Water CCN Utilities …………………………………... 2-7 2.4.2 Wastewater CCN Utilities …………………………….. 2-7 2.5 Climate ……………………………………………………….. 2-10 2.6 Topography …………………………………………………… 2-12 2.7 Transmission System …………………………………………. 2-12 2.8 Impervious Cover …………………………………………….. 2-12 SECTION 3 DATA COLLECTION 3.1 General …..………………………………………………….. 3-1 3.2 Survey ………………………………………………………. 3-1 3.3 Regional Coordination ………………………………………. 3-3 SECTION 4 GROUNDWATER 4.1 Groundwater Sources ………….…………………………….. 4-1 4.1.1 Leona Formation …………………………………….. 4-1 4.1.2 Wilcox Formation …………………………………… 4-3 4.1.3 Carrizo Formation …………………………………… 4-3 4.1.4 Recklaw Formation …………………………………. 4-5 4.1.5 Queen City Sands Outcrop ……………………………. 4-5 4.2 Groundwater Quality ………….…………………………….. 4-5 4.3 Groundwater Conservation Districts ……..……….…………… 4-7 4.3.1 Plum Creek Conservation District (PCCD) ….……….. 4-7 4.3.2 Gonzales County Underground Water Conservation District (GCUWCD) ………………………………... 4-11 SECTION 5 SURFACE WATER 5.1 General …..………………………………………………….. 5-1 5.2 Surface Water Supply Sources …………..………………….. 5-1 5.2.1 Guadalupe River Basin ……………………………… 5-1 TOC-1 Klotz Associates Project No. 0972.000.000 Caldwell County Regional Water and Wastewater Planning Study January 2010 Final Report C O N S U L T I N G E N G I N E E R S TABLE OF CONTENTS CONTINUED Page 5.2.2 Colorado River Basin ……………………………….. 5-3 5.3 Surface Water Supply Uses .………………………………… 5-5 5.4 Surface Water Rights …………………..…………………... 5-5 SECTION 6 POPULATION 6.1 Population Projections …………….…....…………………… 6-1 6.2 Texas State Data Center …………….….………………….. 6-1 6.3 Texas Water Development Board ………..………………… 6-2 6.4 Population History and Growth Estimates …………………..... 6-4 6.5 Population Consensus ………………………………………... 6-5 SECTION 7 FACILITIES INVENTORY 7.1 Water Facilities Inventory …………...………………………. 7-1 7.1.1 Aqua Water Supply Corporation …………………….. 7-3 7.1.2 City of Lockhart ………………………………………. 7-4 7.1.3 Creedmoor Maha Water Supply Corporation .……… 7-4 7.1.4 City of Luling ...……………………………………… 7-4 7.1.5 County Line Water Supply Corporation …………… 7-5 7.1.6 Goforth Special Utility District ………………………. 7-5 7.1.7 Gonzales County Water Supply Corporation .………. 7-6 7.1.8 TriCommunity Water Supply Corporation ………… 7-6 7.1.9 Martindale Water Supply Corporation ………………. 7-7 7.1.10 Maxwell Water Supply Corporation ……………….. 7-7 7.1.11 Polonia Water Supply Corporation ………………….. 7-8 7.1.12 City of San Marcos ………………………………… 7-8 7.2 Regional Water Wholesalers ………………………………… 7-8 7.2.1 Canyon Regional Water Authority ………………… 7-8 7.2.2 Guadalupe Blanco River Authority ………………… 7-9 7.3 Wastewater Facilities Inventory …………………………… 7-10 7.3.1 The City of Lockhart/ GBRA ……………………… 7-10 7.3.2 The City of Luling …………………………………… 7-12 7.3.3 Turner Crest Village Wastewater Company, LLC … 7-13 7.3.4 Mustang Plaza ……………………………………… 7-13 7.3.5 Sweetwater Utility, LLC …………………………… 7-13 7.3.6 Additional State Wastewater Permits ……………….. 7-14 SECTION 8 WATER DEMANDS 8.1 Historical Water Use ……….………..………………………. 8-1 8.2 TWDB Water Use Projections ....…....………....................... 8-3 8.3 Development of Water Demands …...……………………… 8-7 8.4 Conservation Measures ……………………………………… 8-11 TOC-2 Klotz Associates Project No. 0972.000.000 Caldwell County Regional Water and Wastewater Planning Study January 2010 Final Report C O N S U L T I N G E N G I N E E R S TABLE OF CONTENTS CONTINUED Page SECTION 9 WASTEWATER FLOWS 9.1 General ………………………………………………………… 9-1 9.2 Wastewater Flow …………..………....................................... 9-1 9.3 Wastewater Loads …………………………………………… 9 - 3 SECTION 10 WATER QUALITY 10.1 General ….……………………………………………………. 10-1 10.2 City Ordinances ……………………………………………… 10-1 10.3 United States Environmental Protection Agency (USEPA) ….. 10-2 10.3.1 The National Pollutant Discharge Elimination System (NPDES) ……………………………………………… 10-2 10.4 Texas Commission on Environmental Quality (TCEQ) ……… 10-2 10.4.1 The Texas 303(d) List ………………………………… 10-3 10.4.2 Texas Pollutant Discharge Elimination System (TPDES) 10-3 10.4.3 Source Water Protection …………………………….. 10-4 10.5 Total Maximum Daily Loads (TMDL) Program …………….. 10-4 10.6 Plum Creek Watershed Protection Plan …….……………….. 10-4 10.6.1 E.coli Potential ………………………………………. 10-6 10.7 Seasonal Loading Impacts ………..………………………….. 1 0 - 6 SECTION 11 WATER SUPPLY OPTIONS 11.1 Regional Water Plans ………………………………………… 11-1 11.1.1 GBRA Mid-Basin Project ……………………………… 11-3 11.1.2 Hays Caldwell Public Utility Agency Supply Project (HCPUA) ……………………………………………. 11-4 11.1.3 Lower Guadalupe Water Supply Project for GBRA Needs …………………………………………………. 11-6 11.1.4 Lockhart Reservoir …………………………………… 11-6 11.1.5 Recycled Water Programs ……………………………. 11-6 11.1.6 Surface Water Rights …………………………………. 11-7 11.1.7 Local Carrizo ………………………………………….. 11-7 11.1.8 Local Storage ………………………………………….. 11-8 11.1.9 The Simsboro Aquifer ………………………………… 11-10 11.1.10 Weather Modification ……………………………… 11-10 11.1.11 Rainwater Harvesting ………………………………... 11-11 11.1.12 Water Conservation Strategy ………………………... 11-11 11.1.13 Desalination ………………………………………….. 11-12 11.2 Conclusions ………….……………………………………….. 11-12 SECTION 12 REGIONAL WATER PLANNING 12.1 General ……………………………. …………………………. 12-1 12.2 Water Supply Sources ...…………………………...………...... 1 2 - 2 TOC-3 Klotz Associates Project No. 0972.000.000 Caldwell County Regional Water and Wastewater Planning Study January 2010 Final Report C O N S U L T I N G E N G I N E E R S TABLE OF CONTENTS CONTINUED Page 12.3 Conceptual Planning …..……………………………………… 12-4 12.3.1 Source Development …………………………………. 12-4 12.3.2 Distribution …………………………………………… 12-7 12.4 Water System Cost Estimates ………………………………… 12-9 SECTION 13 REGIONAL WASTEWATER PLANNING 13.1 Introduction ………………………..………………………….. 13-1 13.2 Existing Wastewater Collection Systems ……………………… 13-1 13.3 Wastewater System Planning …………………………………. 13-3 13.4 Wastewater Collection System Service Areas ………………… 13-3 13.5 Wastewater Collection System Options ………………………. 13-6 13.5.1 On-Site Sewage Facilities (OSSF)/ Septic Systems ……. 13-6 13.5.2 Regional Treatment Facilities …………………………. 13-7 13.5.3 Decentralized Treatment Facilities ……………………. 13-7 13.5.4 Package Treatment Facilities …………………………. 13-8 13.6 Proposed Wastewater Collection Facilities …………………… 13-10 13.6.1 Option 1 – Regional Facilities ………………………… 13-11 13.6.2 Option 2 – Decentralized/ Package Treatment Systems 13-11 13.6.3 Option 3 – Combined Facilities ………………………. 13-12 13.7 Proposed Regional Wastewater Facilities …………………….. 13-12 SECTION 14 REGIONAL WATER QUALITY PROTECTION PLAN 14.1 Introduction ………………………………………………...…. 14-1 14.2 Caldwell County Watersheds …….…………………………… 14-1 14.3 Water Quality Concerns and Sources of Impairment …….…… 14-2 14.4 Water Quality Standards ……………………………………… 14-3 14.5 Impairment Locations …………………………………………. 14-5 14.6 Recommended Load Reductions ……………………………… 14-6 14.7 Proposed Management Measures …………………………….. 14-6 14.7.1 Urban Stormwater Management Measures …………… 14-7 14.7.2 Water Quality Development Ordinances and Policy …. 14-8 14.8 Structural BMPs for Discharges from Developed Land ……… 14-9 14.8.1 Infiltration Systems ……………………………………. 14-9 14.8.2 Detention Sedimentation Basins ………………………. 14-9 14.8.3 Vegetative Filter Strips ……………………………….. 14-10 14.8.4 Vegetative Swales …………………………………….. 14-10 14.8.5 Riparian Buffers ……………………………………… 14-10 14.8.6 Rain Gardens …………………………………………. 14-10 14.9 Agricultural Best Management Practices …………………….. 14-11 14.10 Public Education/ Outreach ….………………………… …… 14-13 TOC-4 Klotz Associates Project No. 0972.000.000 Caldwell County Regional Water and Wastewater Planning Study January 2010 Final Report C O N S U L T I N G E N G I N E E R S TABLE OF CONTENTS CONTINUED Page 14.11 Municipal Practices and Good Housekeeping ………………………. 14-13 14.12 Implementation Recommendations for the CCRWQPP ……………. 14-14 14.12.1 Point Discharge Load Reductions ………………………… 14-14 14.12.2 Stormwater Filter Strips Along Streams …………………. 14-20 14.12.3 Water Quality Remediation Associated with Impervious Cover ……………………………………………………. 14-21 14.12.4 OSSF Annual Inspection and Certification …………….. 14-22 SECTION 15 REGIONAL WATER QUALITY IMPLEMENTATION 15.1 General ……………………………………………………….. 15-1 15.2 Stormwater Management Implementation …………………… 15-1 15.3 Development of Ordinances ………………………………….. 15-3 15.4 Regional Agreement ………………………………………….. 15-3 15.5 Funding ………………………………………………………… 15-3 SECTION 16 SUMMARY OF RECOMMENDATIONS FOR WATER AND WASTEWATER FACILITIES 16.1 Introduction ………………………..………………………….. 16-1 16.2 Recommended Regional Water Supply Facilities …………… 16-1 16.3 Recommended Regional Wastewater Treatment Facilities …. 16-4 TOC-5 Klotz Associates