TWCA Annual Convention: Securing the Water Future of the Greater Houston Region, Turco, Chang, Evans, and Vinson
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Securing the Water Future of the Greater Houston Region: A Collaborative Effort to Meet
the Region's Projected Growth and Future Water Demand while Reducing Rates of Subsidence
March 3, 2016
Mike Turco -- Harris Galveston Subsidence DistrictJun Chang, P.E. -- City of Houston
Mark Evans -- NHCRWAAlia Vinson -- Allen Boone Humphries Robinson LLP
A Brief History of Subsidence and Groundwater Regulation
• Groundwater served as the primary source water for the rapid growth of the Houston Regional Area over the last century.
• Nearly a century ago, development of the Goose Creek Oilfield, a shallow play near Baytown, TX resulted in nearly 3 feet of Subsidence in that
area.
• Goose Creek Oilfield was the first documentedcase linking shallow fluidwithdrawal from the GulfCoast Aquifer System and subsidence.
Groundwater Use and Subsidence
Groundwater Use and Subsidence• Prior to WWII groundwater use due to industrial and
petrochemical development near Baytown and Texas City were the primary contributors to subsidence.
• After WWII as groundwater useincreased to support rapid industrial and municipal growth.
• As a result of the growing subsidence risk to major elementsof the Houston Economy, includingthe Port of Houston, Industry, NASA Johnson Space Center, and the Texas Medical Center, in 1975 the Texas Legislature created the Harris-Galveston Subsidence District.
Brownwood - 1944
Brownwood - 1953
Brownwood - 1978
Brownwood - 2002
Brownwood - 2016
Subsidence Impacts
• Following the creation of the District, groundwater regulation began nearest the coast in the ACE
• By the early 1990’s subsidence rates in the ACE had generally reduced to near zero, however, rates of groundwater level decline and subsidence were increasing in areas further inland.
• The 1992 District regulatory plan expanded the area required to reduce groundwater usage to all of Harris County.
Regulating Groundwater to Stop Subsidence
Groundwater Regulation and Alternative Supplies
Groundwater Regulation and Alternative Supplies
Groundwater Regulation and Alternative Supplies
1915-2001 Subsidence Harris County
Groundwater Level Change in the Evangeline Aquifer 1977-2015
Subsidence 2000 – 2010
• Areas 1 and 2 – Fully Converted• Area 1 GW Reduced to 10% or
less of TWD• Area 2 GW Reduced to 20% or
less of TWD• Area 3
• GW Reduced to 70% or less of TWD 2010
• GW Reduced to 40% or less of TWD 2025
• GW Reduced to 20% or less of TWD 2035
• Exemptions: Agricultural Irrigation
2013 Regulatory Plan
1
3
2
Collaborative Regional Water Planning
Past Successes:Visionary Planning
• Overall Water Supply Area: 1,550 square miles• Four Counties• Water Customers Served: 4.6 million• Provide Surface Water to the Four Regional Water Authorities:
North Harris County Regional Water Authority West Harris County Regional Water Authority Central Harris County Regional Water Authority North Fort Bend Water Authority
Houston’s Water Supply Overview
Historical Projects - Storage
1969 – Lake Livingston Storage: 1.7Million Acre-feet
• 806 MGD 1954 – Lake Houston
Storage:160,000 Acre-Feet• 198 MGD
1973 – Lake Conroe Storage: >416,00 Acre-feet
• 60 MGD
Houston – Water Treatment
East Water Purification Plant 350 MGD
Southeast Water Purification Plant 200 MGD
Northeast Water Purification Plant 80 MGD
Houston Raw Water Resources
Surface Water Supply by Source
Lake Conroe6%
Lake Houston16%
Lake Livingston78%
Current Production by Source
Ground Water20%
Lake Houston16%
Lake Livingston64%
Houston’s Current Water Supply
Surface Water Supply = 1,551 Million Gallons/Day
Lakes & Rivers
Reuse
Bayous
Ground
Challenges of Developing New Water Supplies: The 2025 Conversion
Phased groundwater reduction mandate for NW Harris Co. area
• 2010 – 30% (achieved)• 2025 – 60%• 2035 – 80%• Disincentive Fee - $7/1000 gallons
How Can These Challenges Be Overcome?
• Regional cooperation among governmental entities to swiftly develop water projects together
• The City of Houston, the North Harris County Regional Water Authority, the West Harris County Regional Water Authority, the Central Harris County Regional Water Authority, the North Fort Bend Water Authority, and the Coastal Water Authority have worked together to develop and finance the water supplies needed to meet future water demands and to comply with Subsidence District requirements.
• Regular communication between the Subsidence District and these entities keeps the regulators informed of the status of projects and compliance with the Regulatory Plan.
Future Water Supplies
• Luce Bayou Interbasin Transfer Project – Raw water supply transfer from Trinity River to Lake Houston
• Northeast Water Purification Plant (NEWPP) Expansion -- Treated water supply from Lake Houston
• Transmission Lines from NEWPP• Internal Distribution Systems
Luce Bayou Facts
• Transfer of Trinity River Water• Capacity 500 MGD• ~ 26 miles of pipeline/canal• RW Pump Station• ~Cost $350 Million• Coastal Water Authority sponsored,
participants include COH, WHCRWA,NHCRWA, NFBWA and CHCRWA
Luce Bayou
• Phased expansion of City’s Northeast Water Purification Plant
• Increases from 80MGD to 400MGD
More Treatment Capacity Needed
Northeast Water Purification Plant Expansion
• Project sponsored by the City of Houston but jointly funded by WHCRWA, NHCRWA, CHCRWA, and NFBWA
• Project costs estimated at $1.28B• Sized to meet 2040 water
demands
Northeast Transmission Line• Project sponsored by the City, but jointly funded
by NHCRWA and CHCRWA (short segment #1 of the line (2200 ft) is also funded by WHCRWA and NFBWA).
• Estimated cost is $445M.• 108 inch water line approx. 12 miles long (to
NHCRWA).
Northeast Transmission Line
• Sample formatSurface Water Supply Project
Transmission Line• Project managed by the WHCRWA, but
jointly funded by WHCRWA/NFBWA• Estimated cost is $600M• 96-inch water line approximately 39 miles
long
Surface Water Supply Project
• Sample formatNHCRWA
Distribution System
• Sample formatWHCRWA Internal
Distribution Projects
Continued Challenges: Funding Regional Projects
• Sample formatState Water Implementation Fund
for Texas (SWIFT)• The SWIFT was created by HB4
• Constitutional amendment (Prop 6) passed on November 5, 2013
• $2 billion was transferred from the Rainy Day Fund
• Fund projects in the State Water Plan
• Only political subdivisions and nonprofit water supply corporations are eligible for funds
• At least 20% for water conservation and reuse projects
• At least 10% for serving rural and agricultural needs
Funding For Regional Water Projects
• The City and the four regional Water Authorities have already spent more than $2.5B to comply with Subsidence District conversion requirements.
• The City and the four regional Water Authorities are expected to spend >$3B of additional infrastructure by 2025 (including NEWPP Expansion, Luce Bayou, Transmission Lines, and Distribution Lines).
Funding For Regional Water Projects (continued)
• Additional costs are expected to meet 2035 requirements and beyond.
• Capital costs are financed using tax-exempt bonds.
• The Water Authorities do not have taxing authority and debt service is paid for by GRP (groundwater pumpage) fees and surface water fees.
TWDB SWIFT Funding• The Texas Water Development Board
SWIFT/SWIRFT programs have facilitated the development of these regional water projects.
• The SWIFT program’s first round of funding in 2015 provided funding for all qualified projects that applied.
• All of the projects described in this presentation received some SWIFT funding, which allowed bonds to be sold to the TWDB for these projects at low-interest rates saving millions of dollars over the life of the bonds.
What’s Next?: Long Term Planning
Long-Term Water Supply Strategies
• Reuse• Additional Surface Water• Importation of Groundwater• Desalination• Conservation
Contacts
Mike TurcoHGSD
1660 West Bay Area Blvd.Friendswood, TX 77546mturco@subsidence.org
(281) 486-1105
Mark Evans NHCRWA
3648 Cypress Creek Pkwy. Houston, Texas 77068mevans@nhcrwa.com
(281) 440-3924
Jun ChangCity of Houston611 Walker Street, 25thHouston, Texas 77002
jun.chang@houstontx.gov(832) 395-2464
Alia VinsonABHR
3200 SW Fwy, Suite 2600Houston, Texas 77027
avinson@abhr.com(713) 860-6449
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