WHY DID MISSOURI CITY ADOPT A JOINT WHY DID MISSOURI CITY ADOPT A JOINT GROUNDWATER REDUCTION PLAN?GROUNDWATER REDUCTION PLAN?

A subdivision in Baytown, located in Harris A subdivision in Baytown, located in Harris County, has been turned into a park and is now County, has been turned into a park and is now underwater because of the sinking of the land. underwater because of the sinking of the land.

Why Reduce Groundwater Usage?Why Reduce Groundwater Usage? To prevent subsidence contributing to:• Flooding • Rising waters resulting from storms or hurricanes• Lowering of groundwater capacities

What is subsidence?When pumping large amounts of groundwater from underground aquifers, the clay compacts and the elevation of the land surface sinks.

What does subsidence look like?What does subsidence look like?Examples of subsidence in the Greater Houston area

1 ft.

2 ft.

3 ft.4 ft.

5 ft. 6 ft.

Showing drop in ground elevation

7 ft. 8 ft.

9 ft.

10 ft.

Missouri City Joint Groundwater Reduction PlanMissouri City Joint Groundwater Reduction Plan

The City of Missouri City, in partnership with other entities, prepared a joint Groundwater Reduction Plan (GRP) to comply with Fort Bend

Subsidence District requirements for reduction of groundwater use.

Fort Bend Subsidence District •1989: Created for the regulation and withdrawal of groundwater to prevent subsidence.

•1998: The Texas Water Development Board certified FBSD’s Groundwater Management Plan, which set 5 goals:

1. Provide for the efficient use of groundwater 2. Control and prevent waste of groundwater3. Control and prevent subsidence4. Address conjunctive surface water management5. Address groundwater natural resources issues

Groundwater vs. Surface WaterGroundwater vs. Surface WaterGroundwater and surface water are linked together through the hydrologic cycle

Groundwater Surface water 1. Once polluted very hard and expensive to clean 1. Once polluted can be cleaned and fairly

inexpensive 2. Sources diminishing 2. Few effects on the environment 3. Adverse effects on the environment 3. Ability to be expanded for larger demand (for example, subsidence)

The end product will be similar for all drinking waterGroundwater and surface water both have to meet the same federal and state quality standards for drinking water

Groundwater Reduction Goals for Groundwater Reduction Goals for Missouri CityMissouri City

The City of Missouri City and its partners will meet the following Subsidence District

requirements:

• January 2013: Will reduce and maintain groundwater withdrawals to no more than 70% of participants’ total water demand.

• January 2025: Will reduce and maintain groundwater withdrawals to no more than 40% of each participants’ total water demand.

Who Will be Converted to Surface Water? Who Will be Converted to Surface Water? • The Missouri City Joint GRP established the most cost-effective

method of meeting the Subsidence District requirements

• January 2013 : Convert entities in the City’s southern portion (Sienna Plantation) to meet 30 % reduction

• As the 60% reduction requirement approaches in 2025, convert

additional entities, generally moving northward on the system.

(Picture: Initial converting entities)

Surface Water Source and TreatmentSurface Water Source and Treatment

• Initial Surface Water Supply– Brazos River

• Surface Water Treatment Plant• Initial capacity of 10 million gallons per day of drinking

water– Built-out capacity of over 30 MGD

Cost to Implement Missouri City Joint GRP Cost to Implement Missouri City Joint GRP • Phase 1

– 10 MGD surface water treatment plant and transmission pipelines to Sienna Plantation Water Plants 1 &2

• Pumpage fee for all participants• At a cost per 1,000 gallons of water used• Fees determined each year through budgeted annual costs and projected

water use• At budget year end, a “true-up” will assure no single entity bears any

more risk than any other participating entity

Detailed Project Cost

Cost Comparison Cost Comparison • “The Do Nothing Option”

– If the Joint GRP plan was not being implemented, the Fort Bend Subsidence District would implement a fee of $3.50/1,000 gallons pumped.

• The Current Pumpage Fee– Effective July 1, 2009, the pumpage fee is $1.10/1,000 gallons pumped.

• The Estimated Future Pumpage Fee– The estimated future pumpage fee after plant construction is approximately

$2.35/1,000 gallons pumped.

Estimated GRP Plan Savings to Participants:

$1.15 per 1,000 gallons pumpedor

$11.50 per month for the average home

SourcesSources• Information

– Subsidence Districts• www.subsidence.org/

– Fort Bend Subsidence District» www.fbsubsidence.org/

– Harris Galveston Subsidence District» www.hgsubsidence.org/

– Missouri City Joint Groundwater Reduction Plan • Pictures

• www.csr.utexas.edu• www.subsidence.org• www.ruf.rice.edu

• Other Related Links• geochange.er.usgs.gov/sw/changes/anthropogenic/subside/• asthecourtturns.blogspot.com/2009/02/is-fort-bend-sinking.html• www.twdb.state.tx.us/wrpi/rwp/rwp.htm