Aquifer Storage And Recovery Feasibility Study

Aquifer Storage And Recovery for City of Buda, Texas Feasibility Summary and Pilot Well Plan November 21, 2017

Presentation • ASR Definition • Desktop Feasibility Summary

• Proposed Pilot Project Scope and Schedule

2

Typical ASR Installation

Raw Water Withdrawal Raw Water Storage Water Treatment Plant

Treated Water ASR Well

Treated Water Storage

3

Seasonal Storage Monthly Demand Annual Average Demand

ASR Recovery

ASR Storage

ASR Storage

J 4

F

M

A

M

J

J

Months

A

S

O

N

D

Recharge

Recovery

ASR Well

ASR Well

Ground Storage

Pump Station

Ground Storage

Distribution System

Edwards Well

5

Desktop Feasibility Scope • Source Water Assessment • Groundwater Assessment

• Permitting Considerations • Application and Feasibility

6

Pump Station

Edwards Well

Distribution System

Source Water Assessment

Source Water Assessment • Compiled existing and planned supplies

• Compiled existing and planned demands • Quantified average day and peak day deficits and assess opportunities for Drought and seasonal ASR applications

8

Average Day 6.0 5.0 4.0 Supply (mgd)

3.0

Demand (mgd)

2.0

Drought Supply (mgd) 1.0 0.0 2010

2020

2030

2040

2050

2060

2070

9

Peak Day 12.0 10.0 8.0

6.0 Supply (mgd) 4.0

Demand (mgd)

2.0 0.0 2010

10

2020

2030

2040

2050

2060

2070

Groundwater Assessment

Hydrogeology • Middle Trinity – Limestone Person Formation

– Dolomite

Kainer Formation

– Fine-grained sand and siltstone

• Lower Trinity – Sandy, pebbly conglomerates – Dolomitic limestone

12

Storage Zone Selection • Middle and lower Trinity similar well capacity • Low density of existing wells in both aquifers

• Similar assumed regional flow velocity in both aquifers • Lower Trinity 500 feet deeper than middle Trinity; more expensive • Middle Trinity