HomeMy WebLinkAbout2024-03-08-water-conservation-design-standards
5450 N. Riverside Drive Fort Worth, Texas 76137
Starting January 1, 2024, all TCCD projects shall comply with the "Water Conservation Design Standards for State
Buildings and Institutions of Higher Education Facilities" prepared by SECO, dated April 2020. The following
document provides the SECO standards for your reference.
In addition, before beginning construction of a new state building or state-supported higher education facility,
a water conservation compliance certification form must be completed and submitted to the SECO to document
compliance with the standards. A copy of this form is included in the separate file named “50-811 Water
Conservation Compliance Cert.”
Send completed forms to:
State Energy Conservation Office
Attn: John Kyere
111 E. 17th St., Suite 610D
Austin, TX 78701
For more information, contact John Kyere, 512-463-4867.
Water Conservation Design Standards
For State Buildings and Institutions
of Higher Education Facilities
Effective: January 1, 2021 Published: April 2020
STATE ENERGY CONSERVATION OFFICE
TEXAS COMPTROLLER OF PUBLIC ACCOUNTS
111 East 17th Street, Room 314
Austin, Texas 78701
Water Conservation Design Standards
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ACKNOWLEDGEMENTS
The State Energy Conservation Office (SECO) wishes to thank the tireless representatives of various state
agencies and higher educational institutions that provided technical, policy and regulatory advice during the
development of the updated Water Conservation Design Standards. SECO would like to acknowledge the
members, as well as their respective organizations, for their time and invaluable input.
The Water Conservation Standards Work Group includes:
Robert Barrera, University of Texas System
Frederick Beebe, Texas Department of Transportation
Joseph Bougard, Texas Military Department
Tarek Bou-Saada, The Health and Human Services Commission
Andee Chamberlain, Texas Parks and Wildlife
Debra Durda, Texas Department of Criminal Justice
Shirley Ellis, Texas A&M University, Energy Systems Laboratory
Bill Hoffman, H.W. Hoffman & Associates, LLC
Sally Kachoris, Texas Workforce Commission
Tim Loftus, Texas State University
Pat Mazur, The University of Texas at Austin
Doug Powell, The University of Texas System
Rene Rodriguez, The University of Texas at Austin
Farshad Shahsavary, Texas Facilities Commission
John Sutton, Texas Water Development Board
Eddy Trevino, State Energy Conservation Office
Bahman Yazdani, Texas A&M University, Energy Systems Laboratory
Fred Yebra, State Energy Conservation Office
Water Conservation Design Standards
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Table of Contents
BACKGROUND ............................................................................................................................................... 1
INTRODUCTION ............................................................................................................................................. 1
PURPOSE OF WATER CONSERVATION STANDARDS...................................................................................... 1
IMPLEMENTATION OF THE WATER CONSERVATION STANDARDS ............................................................... 2
OVERVIEW .................................................................................................................................................... 2
DEFINITIONS ................................................................................................................................................. 3
ABBREVIATIONS ............................................................................................................................................ 4
1.0 IRRIGATION AND LANDSCAPE DESIGN ................................................................................ 5
STANDARDS FOR IRRIGATION ...........................................................................................................................5
STANDARDS FOR LANDSCAPE DESIGN .............................................................................................................. 5
2.0 HEATING, VENTILATION AND AIR CONDITIONING ............................................................... 7
STANDARDS FOR HEATING, VENTILATION AND AIR CONDITIONING ................................................................ 7
STANDARDS FOR COOLING TOWERS .............................................................................................................. 8
STANDARDS FOR STEAM BOILERS................................................................................................................... 9
3.0 REFRIGERATON AND WATER TREATMENT ........................................................................ 9
STANDARDS FOR REFRIGERATION .................................................................................................................. 9
STANDARDS FOR WATER TREATMENT ........................................................................................................... 9
4.0 RAINWATER HARVESTING, RECLAIMED WATER, RECYCLED WATER, AND REUSE ............ 10
STANDARDS FOR RAINWATER HARVESTING ................................................................................................... 10
STANDARDS FOR RECLAIMED WATER, RECYCLED WATER AND REUSE ......................................................... 11
5.0 PLUMBING FIXTURES AND PUMPS .................................................................................... 11
STANDARDS FOR PLUMBING FIXTURES .......................................................................................................... 11
STANDARDS FOR PUMPS ...................................................................................................................................................... 11
6.0 LAUNDRY ............................................................................................................................ 12
STANDARDS FOR LAUNDRY.............................................................................................................. 12
7.0 FOOD SERVICE .................................................................................................................... 12
STANDARDS FOR WAREWASHING ................................................................................................................. 12
STANDARDS FOR GARBAGE DISPOSALS ........................................................................................................ 13
STANDARDS FOR STEAMERS, STEAM TABLES AND COMBINATION OVENS ................................................. 13
8.0 METERING .......................................................................................................................... 14
STANDARDS FOR METERING ......................................................................................................................... 14
9.0 VEHICLE SERVICES AND WASHING..................................................................................... 15
STANDARDS FOR VEHICLE SERVICES ............................................................................................................. 15
STANDARDS FOR VEHICLE WASHING ........................................................................................................... 15
10.0 LAB FACILITIES .................................................................................................................... 15
STANDARDS FOR LAB FACILITES INCLUDING PHOTOGRAPHY AND MEDICAL ............................................... 15
11.0 POOLS, SPAS AND SPECIAL WATER FEATURES STANDARDS FOR POOLS AND SPAS .......... 16
STANDARDS FOR SPECIAL WATER FEATURES ................................................................................................ 17
REFERENCES ................................................................................................................................ 18
Water Conservation Design Standards
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BACKGROUND
In 2001, the 77th Texas Legislative session directed SECO to develop a set of water efficiency standards
for state-funded buildings (Tex. Gov. Code §447.004). With help from the Texas Water Development
Board and the City of Austin Water Conservation Office, SECO developed the Texas Water Guidelines in
2002. In 2011 and 2016, the guidelines were revised and titled the Texas Water Conservation Design
Standards. This is the third revision of those standards.
The Standards shall be followed for new state facilities and major renovation projects as defined by
Texas Administrative Code Rule §19.33 (Tex. Admin. Code §19.33). The Standards should also be
considered when purchasing new equipment, making modifications to existing systems, or equipment
that equals more than half the original purchase price of the equipment. The Standards should also be
considered when upgrading existing equipment that works but is nearing the end of its life expectancy.
A systematic approach should be used when examining water use and using the Standards. The final
goal of the Standards is to balance water, wastewater, energy and related costs to achieve the lowest
life cycle costs when purchasing new equipment, replacing old equipment or making modifications to
existing equipment.
INTRODUCTION
Many communities in Texas have investments in water conservation and efficiency. These investments
have resulted in reductions in per capita demand and water supply system efficiency. Significant
opportunity still exists for greater water-use efficiency that will result in economic, public health and
environmental benefits.
Texas’ economy is directly linked to its natural resources. Water is a critical natural resource that is
affected by rainfall and development. Seasonal rainfall varies significantly from year to year.
Development and weather can severely deplete water supplies.
Water conservation and efficiency is critical to ensuring the state’s long-term economic health. It is
becoming increasingly important as water demand rises.
PURPOSE OF WATER CONSERVATION STANDARDS
These Water Conservation Design Standards set targets for water conservation and water-use
efficiency. These Standards also provide guidance on effective conservation measures to meet the
statewide goals identified in Texas Government Code §447.004.
Water conservation is a strategy or combination of strategies for reducing the volume of water
withdrawn from a water supply source, for reducing the loss or waste of water, for maintaining or
improving the efficiency in the use of water, for increasing the recycling and reuse of water and for
preventing the pollution of water. In this document the terms water conservation and water efficiency
are used interchangeably.
The Standards focus on water conservation best management practices (BMP). BMPs are efficiency
measures that save a quantifiable amount of water, either directly or indirectly, and can be
implemented within a specific time frame. The Standards are achievable, implementable and practical
measures that should be used in the planning, construction and renovation of buildings used by state
agencies and higher education institutions.
Water Conservation Design Standards
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IMPLEMENTATION OF THE WATER CONSERVATION STANDARDS
The Water Conservation Design Standards shall be followed in all new construction and major
renovation activities. These Standards should be considered in all programs affecting the planning and
management of Texas’ water resources. The Standards and recommendations outlined in this
document reflect the most current technical and operational knowledge about water-use efficiency.
OVERVIEW
The Standards’ goals are to:
1. Implement water conservation in all new state‐owned buildings to accurately account for water use
and demonstrate water saving techniques and concepts to the public.
2. Integrate water conservation and efficiency measures into all aspects of state‐owned buildings
including: major renovation projects; purchase of new related equipment to replace existing
equipment; modifications to existing systems; and upgrades to existing equipment.
3. Maximize the efficiency of public water supply systems.
4. Promote public awareness of the long-term economic and environmental benefits of conserving
water.
Water Conservation Design Standards
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DEFINITIONS
Alternative onsite water- means rainwater, air-conditioner condensate, foundation drain water,
storm water, cooling tower blowdown, swimming pool backwash and drain water, reverse osmosis
reject water, or any other source of water considered appropriate by the Texas Commission on
Environmental Quality (TCEQ).
Automatic shut‐off device - an active system that stops the flow of water automatically when a leak is
detected or a programmable system that stops the flow of water when the equipment is not in use.
Blowdown – the portion of the circulating water flow in a heat transfer process that is removed
in order to maintain the amount of dissolved solids and other impurities at an acceptable level.
Closed loop system- a system that has no contact with the outside environment.
Economic feasibility study - a cost benefit analysis of a system based on the expected life, cost,
maintenance and materials of the system as compared with the cost of water saved. For automatic
implementation, the cost benefit analysis will yield a breakeven point of no more than one-third the
expected life of the system, which shall be a maximum of 30 years.
EPA ENERGY STAR - a joint program of the U.S. Environmental Protection Agency (EPA) and the U.S.
Department of Energy (DOE) helping to save money and protect the environment through energy-•‐
efficient products and practices.
EPA WaterSense - an EPA-sponsored partnership program that seeks to protect the future of the nation's
water supply by promoting water efficiency and enhancing the market for water-efficient products,
programs and practices.
Graywater - wastewater from clothes-washing machines, showers, bathtubs, hand-washing lavatories,
and sinks that are not used for disposal of hazardous or toxic ingredients. Graywater does not include
wastewater that has come in contact with toilet waste; from washing of material, including diapers,
soiled with human excreta; or from sinks used for food preparation or disposal.
Make‐up water - the water feed needed to replace that which is lost in a heat transfer process by
evaporation or leakage in a closed loop system.
Non‐potable water - water that is not suitable for drinking.
Once through cooling - water that is pumped through heat exchange equipment and then discharged
into the environment.
Potable water - water that is fit for consumption by humans and other animals.
Rainwater harvesting - the capture, diversion, and storage of rainwater for a variety of purposes
including landscape irrigation, drinking and domestic use, aquifer recharge and storm water abatement.
Reclaimed water - water from domestic or municipal wastewater that has been treated to a quality
suitable for beneficial use.
Recycled water - water, which as a result of treatment of waste, is suitable for a direct beneficial use or
a controlled use that would not otherwise occur.
Reuse is defined as treated wastewater that can be used for beneficial purposes.
Self‐closing - a device, usually in a faucet or nozzle, which must be turned on by the user by pushing or
pulling and is turned off when the user releases the handle or tap.
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Water Conservation Design Standards
ABBREVIATIONS
BMP – Best Management Practices
EPA – Environmental Protection Agency
F – Fahrenheit
cfm – cubic feet per minute
gpd – gallons per day
gpf – gallons per flush gpm – gallons per minute gr - grains
psi – pounds per square inch
RO - reverse osmosis
SECO – State Energy Conservation Office
TCEQ – Texas Commission on Environmental Quality
TWDB – Texas Water Development Board
IMEF – Integrated modified energy factor, in (cu ft/kWh/cycle)
IWF – Integrated water factor, in (gal/cu ft/cycle)
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Water Conservation Design Standards
1.0 IRRIGATION AND LANDSCAPE DESIGN
STANDARDS FOR IRRIGATION 1. Automatic irrigation systems shall comply with TCEQ’s Water Code 12 Texas OCCUPATIONS CODE
CHAPTER 1903, and 30 Tex. Admin. Code Title §344 and all local requirements.
2. Landscape irrigation systems of 2,500 square feet or greater shall be separately metered (see
Section 8.0 Metering)
3. Irrigation shall employ drip, trickle, micro, low-arching, multi-stream rotational or other water-
conserving technology where possible.
4. Adjustable flow control valves shall be provided on circuit remote control valves.
5. Automatic irrigation systems shall be equipped with a flow meter that stops system operation
to prevent unintended waste of water from damaged or malfunctioning components.
6. Automatic irrigation systems shall be equipped with a controller capable of dual or multiple
programming. Controllers shall have multiple cycle start capacity and flexible calendar
programming, including the capability by day of the week or day to night interval watering. An
economic feasibility study shall be conducted to assess whether the U.S. Environmental
Protection Agency’s WaterSense certified weather-based irrigation controllers will be installed.
7. Automatic irrigation systems shall be equipped with soil moisture sensors and rain and freeze
sensor shut-off devices. Moisture sensors shall be coordinated with landscape design to
ensure effective use.
8. Pressure regulating devices shall be required where water supply static pressure exceeds
manufacturer’s recommended operating range. This component should be installed at the
control valve.
9. Serviceable check valves shall be required where elevation differential may cause low head
drainage adjacent to paving areas.
10. Sprinkler head spacing shall be designed for head-to-head coverage or heads shall be spaced as
per manufacturer’s recommendations and adjusted for prevailing winds. The system shall be
designed for minimum run-off and for a distribution uniformity of at least 65 percent.
11. Sprinkler heads shall not spray water directly on buildings or hardscape areas. The pop-up head
limit shall not be less than four (4) inches.
12. Sprinklers shall not be placed along curbs, in parkways or planting islands less than six feet
wide.
13. An economic feasibility study shall be conducted to assess whether an alternate site-specific
source of non-potable water shall be explored and implemented.
14. Appropriate signage and purple colored pipe is required and shall identify non-potable water
use for irrigation system operation.
STANDARDS FOR LANDSCAPE DESIGN
1. To maximize water retention, all projects designs shall include soil analysis and specifications
appropriate to the geographic region. All landscape planting selections must be appropriate for
the soil as analyzed and amended if required. Selection of native plants for landscaping that are
adaptable to the existing soil conditions is encouraged to minimize the use of soil amendments.
2. Acceptable topsoil shall be free of weeds, stones larger than one inch in diameter and a
minimum of 30 percent organic matter. Up to 20 percent washed sand may be added to clay-
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Water Conservation Design Standards
type soils. Salvaged topsoil obtained from construction areas on site is encouraged to
minimize or avoid importing topsoil from off site. Turfgrass and planting bed areas shall have
a minimum top soil depth as recommended by the regional Texas AgriLife Extension Service.
3. Irrigated turfgrass shall not exceed 50 percent of landscaped areas. Exceptions: dedicated
athletic fields, golf courses and driving ranges.
4. Turfgrass selection shall be determined by facility need and geographic and climatic conditions
and the ability to survive on only normal rainfall. Drought tolerant turfgrass should be
considered.
5. Non-turf planted areas shall have a minimum of two inches or more of mulch and cover soil
surfaces to minimize soil moisture evaporation. To minimize water use, during the
establishment of new plantings, fall installation of landscape is highly recommended, with
winter and spring installations acceptable. Summer installation is strongly discouraged.
6. Plants recommended by the regional Texas AgriLife Extension Service shall be considered
desirable.
7. Invasive plants shall not be used. Invasive plants are defined as not native to the project
site and that cause or likely to cause environmental harm. At a minimum, the list of
invasive species for a project site includes plants in city, county, and regional lists and
state and federal noxious weeds laws. A list of invasive can be found here:
TexasInvasives.org
8. Plants having similar water needs shall be grouped together and selected based on use, soil
conditions, sun and shade conditions, adaptability to geographic and climatic conditions and
the ability to survive normal rainfall or minimal irrigation.
9. Planning to preserve native plants and protection of native plants during construction is
encouraged. Such plants include, but are not limited to:
a. Plants that are threatened or endangered
b. Specimen plants or exceptional examples of a particular species
c. Plants that readily survive relocation and are useful in new or existing landscapes
d. Native trees larger than 6” caliper size
10. The landscape design shall be coordinated with the storm water design to ensure that the
maximum amount of water is retained on the property through the use of storm water BMP's
such as berms, swales, terraces, rain gardens and proper contouring of landscape. Use of roof
rainwater on landscape without damage to landscape (erosion, stagnant water, etc.) is
encouraged and should be considered. Coordinate irrigation moisture sensors in areas where
roof rainwater is used for irrigation.
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Water Conservation Design Standards
2.0 HEATING, VENTILATION AND AIR CONDITIONING
The following standards are based on modern green codes and current state statutes.
Cited standards include:
1. Water Efficiency Standards (ANSI-IAPMO) – 2017 chapters 4 – 7.
2. ASHRAE 181.1 – 2017 chapter 6.
3. International Green Construction Code (ICC) – 2018 chapter 6
4. SECO Water Conservation Design Standards committee
STANDARDS FOR HEATING, VENTILATION AND AIR CONDITIONING
1. Performance and procedural standards will be followed for maximum energy and water
conservation allowed by the latest and most cost-effective technology that is consistent with
the requirements of public health, safety and economic resources, as stated in Texas
Government Code §447.004.
2. Once-through cooling is prohibited for all heating, ventilation, refrigeration and cooling equipment.
3. An economic feasibility study shall be conducted to assess whether harvesting and delivery of
condensate water can be accomplished through gravity drainage or pumping, if condensate
drainage would need to be treated before reuse and any other cost impact.
4. Closed loop, water-cooled equipment shall be used where possible with the exception of open-
cell cooling towers.
5. An economic feasibility study shall be conducted to assess whether hybrid towers and/or
geothermal (ground coil) heat pump units, combined heat and power systems using desiccant
systems for HVAC dehumidification, and the use of air-cooling Variable Refrigerant Volume
systems should be installed.
6. Where installed, leak detection and control devices shall comply with IAPMO IGC115. Leak
detection with control devices shall not be installed where they isolate fire sprinkler
systems.
7. Reclaimed (recycled) or on-site treated nonpotable water used for industrial and
commercial cooling or air-conditioning shall be approved for use by the water/wastewater
utility and the Authority Having Jurisdiction.
a. A drift eliminator shall be used in a cooling system, utilizing alternate sources of water,
where they aerosolized water may come in contact with employees or members of the
public.
b. A biocide shall be used to treat the cooling system recirculation water where the
recycled water may come in contact with employees or members of the public.
8. When examining the cost benefit analysis of dry versus wet cooling, all additional costs of
cooling tower use shall be considered, including:
a. Energy needed to pump water in the chilled water and cooling tower loops;
b. Cost of water and wastewater;
c. Cost of cooling tower water treatment;
d. Cost of labor to operate the towers;
e. A 30-year projection of future water, wastewater and electricity costs;
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Water Conservation Design Standards
f. Capital replacement costs associated with cooling towers compared with dry cooling;
g. Impact of a discharge with a high total dissolved solid content on the environment
including pretreatment and Total Maximum Daily Loading (TMDL) implications, and
h. The benefits of redundant systems offered by the use of many smaller air-cooled or
ground-cooled systems.
STANDARDS FOR COOLING TOWERS
1. Cooling towers shall be fitted with conductivity controllers, overflow sensors, make-up meters,
and blowdown meters to manage make-up water. For cooling towers of 100 tons or more, the
make-up, and overflow meters and overflow alarm shall be connected to the building’s Central
Energy Management System or Utility Monitoring Dashboard.
2. Cooling tower basins shall be constructed of 304 stainless steel or more corrosion resistant
material such as 316 stainless or ceramic materials.
3. The quality of the water recirculating in the cooling tower system shall determine the set point for
blowdown. The following table provides the concentration levels for basins constructed of 304
stainless steel. The blowdown set point should be set at no lower than 90 percent of the controlling
parameter. The controlling parameter is the constituent level which is reached first based on the
water quality analysis. For example, if the conductivity of the makeup water is low but silica is 27
ppm, the cycles of concentration would be limited by silica to no more than five cycles of
concentration based on silica. Where the manufacture allows higher concentrations, these higher
numbers shall be used for setting the blowdown concentrations.
4. Where a contractor company (rout operator) is retained to manage the water treatment for the
cooling tower, the contract shall specify that the following water quality parameters are met.
Controlling Parameters
Parameters for 304 Stainless Steel Tower Basins
Property Concentration
Conductivity (micro-ohms) <4,000
Chlorides (ppm) <400
Calcium Hardness (CaCO3 –ppm) <600
Silica (ppm) <150
Sulfates <250
Langelier Saturation Index (LSI) +2.8
5. For cooling towers of 100 tons or more, the make-up, and overflow meters and overflow alarm shall
be connected to the building’s Central Energy Management System or Utility Monitoring Dashboard.
6. Provide cooling tower with drift eliminators minimize water loss. Cooling towers shall be
equipped with efficiency drift eliminators that achieve drift reduction to 0.002 percent of the
circulated water volume for counter flow towers and 0.005 percent for cross-flow towers.
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Water Conservation Design Standards
AIR CONDITIONING CONDENSATE RECOVERY SYSTEMS 1. For buildings located in warm-humid climate zones (ASHRAE Climate Zones 1A, 2A, 3A) and have
250,000 square feet or more of air-conditioned space, a system to collect air conditioning
condensate for beneficial reuse shall be installed.
STANDARDS FOR STEAM BOILERS
1. Facility heating water systems shall be used unless a steam heating system is economically feasible.
2. Steam boilers shall be equipped with conductivity controllers to control blowdown and makeup
meters on the cold-water supply to the boiler.
3. Steam condensate return systems shall be installed for all steam boilers.
4. Steam boilers shall be fitted with blowdown heat exchangers to transfer heat to feed water.
Where heat recovery can be used beneficially to heat boiler make-up water or for other
purposes, boiler blowdown from steam boilers exceeding 15 psi and 3.4 million BTU’s per hour
(100 HP) shall be directed to a heat recovery system that reduces the temperature of the
blowdown discharge to below 140 degrees Fahrenheit without using tempering water.
STANDARDS FOR WATER HEATING BOILERS (WATER HEATERS WITH MORE THAN 0.5 MILLION BTU’S PER HOUR)
1. The cold-water feed for all water heating systems of 0.5 million BTU’s or more of capacity shall
be equipped with an easily accessible water meter.
2. For water heating systems (boilers) of 1.0 million BTU’s of capacity or more, the cold-water makeup
meter shall be connected to the building’s Central Energy Management System or Utility Monitoring
Dashboard.
3.0 REFRIGERATON AND WATER TREATMENT
STANDARDS FOR REFRIGERATION
1. Use of Domestic Water for once through cooling of equipment is prohibited.
2. Water-cooled refrigeration systems shall be supplied by a re-circulating system.
3. All ice machines shall meet EPA ENERGY STAR certification standards.
STANDARDS FOR WATER TREATMENT
1. Water softeners shall be equipped with demand-initiated regeneration control systems. If
water softening is used, regeneration shall be controlled by actual hardness or by a flow
volume control that is based on the hardness of the water to be softened. Softeners that use
timers for recharging are prohibited.
2. Central reverse osmosis or nano-filtration systems shall reuse reject water for landscape
irrigation or other beneficial purposes where the quality of the reject water allows. (Beneficial
purposes include but are not limited to the following: other process use, cooling tower make-
up, toilet or urinal flushing, vehicle rinse, laundry and aesthetic fountain make-up).
3. Central reverse osmosis systems shall have at a minimum 75 percent recovery rate.
4. Central distillation systems shall recover 85 percent of feed water.
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Water Conservation Design Standards
5. Point-of-Use Reverse Osmosis Water Treatment Systems installed in residential occupancies
shall be provided with automatic shut-off valves to prevent discharge when there is no call for
producing treated water. Reverse osmosis water treatment systems shall be listed to meet
NSF/ANSI Standard 58.
4.0 RAINWATER HARVESTING, RECLAIMED WATER, RECYCLED WATER, AND REUSE
1. Rainwater harvesting, recycled water and reuse systems shall comply with all state and local
laws regarding public safety and health as stated in the Tex. Gov. Code §447.004 and TCEQ
Chapter 210 – Use of Reclaimed Water, Subchapter C.
2. Treated graywater and alternate on-site reclaimed system technologies, including rainwater
harvesting, condensate collection, or cooling tower blowdown, or a combination thereof, for
non-potable indoor use and outdoor water-use shall be incorporated into the design and
construction of each new building with a roof measuring at least 10,000 square feet. Alternative
on-site water is defined as rainwater, air-conditioner condensate, foundation drain water,
storm water, cooling tower blowdown, swimming pool backwash and drain water, reverse
osmosis reject water, or any other source of water considered appropriate by the Texas
Commission on Environmental Quality (TCEQ).
3. Additional alternative onsite water sources can include, but are not limited to: rainwater, storm
water ponds, reverse osmosis and nano-filtration reject water, foundation drain water, pool
backwash water, pool water discharged to maintain water quality, graywater, wastewater
treatment effluent and steam condensate that is not returned to the boiler.
4. Provide SECO with the documentation of the appropriate analysis that determines if
incorporating the design standard is not economically feasible. This shall apply to available
alternative on-site water sources.
STANDARDS FOR RAINWATER HARVESTING
1. Structures connected to the public water supply and containing a rainwater harvesting system
for indoor use shall comply with 30 Tex. Admin. Code § 290(d) and all local requirements.
2. An economic feasibility study shall be conducted to assess whether harvesting and delivery can
be accomplished through gravity drainage or pumping, or if rainwater would need to be treated
before reuse, as well as any other cost impact.
3. Monthly rainfall rates and expected run-off capture shall be analyzed to size the catchment
area and the storage capacity to meet water demand through the longest expected interval
without rain. Reference: TWDB’s The Texas Manual on Rainwater Harvesting, Third Edition,
Chapter 4: Water Balance and System Sizing to determine storage capacity and Appendix B:
Rainfall Data for average precipitation rates.
4. Plumbing and installation guidance for installing a rainwater harvesting system can be found in
“Rainwater Catchment Design and Installation Standards”, from the American Rainwater
Catchment System Association and the American Society of Plumbing Engineers.
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Water Conservation Design Standards
STANDARDS FOR RECLAIMED WATER, RECYCLED WATER AND REUSE
1. On-site reclaimed, recycled and reuse water systems shall be designed, installed and
implemented according to 30 Tex. Admin. Code § 210 and shall comply with local requirements.
2. On-site graywater reuse systems shall be designed, installed and implemented according to 30
Tex. Admin. Code § 285 (h), and shall comply with local requirements.
5.0 PLUMBING FIXTURES AND PUMPS
STANDARDS FOR PLUMBING FIXTURES
1. All plumbing fixtures, toilets, urinals, faucets and showerheads shall comply with state
plumbing standards as administered by the Texas Commission on Environmental Quality
(TCEQ) as well as EPA’s WaterSense Performance Standards, where applicable.
2. Water closets with flush-o-meter valve or tank-type toilets shall have a flow rate no greater
than 1.28 gpf. All toilet fixtures shall be rated for 1,000 grams or 1.28 gpf as certified by the
latest Maximum Performance Test.
3. Flush urinals shall have a flow rate no greater than 0.5 gpf for floor-mounted urinals and a flow rate
of 0.125 gpf for wall-mounted urinals.
4. Faucets in public lavatories shall be fitted with aerators that have a flow rate no greater than 0.5 gpm
where the pressure is greater than 25 psi. Lavatory faucets in public restrooms shall be self‐closing or
shall be equipped with automatic shut‐off devices.
5. Showerheads used for non‐medical purposes, as in dorms, locker rooms, etc., shall have a flow
rate no greater than 2.0 gpm.
6. All drinking water fountains shall have self-closing valves.
7. All water pipes subject to freezing conditions shall be installed with appropriate freeze
protection devices.
8. Special plumbing fixtures other than those mentioned above shall be chosen based on water
and energy efficiency and functionality.
9. Signage requesting that leaks and other plumbing problems be promptly reported to the
appropriate building management authority shall be placed in each restroom, locker room,
kitchen, laundry, pool and other high water-use area. The signage shall be labeled with a phone
number to report such problems.
10. Non-potable water may be used for flushing in new buildings in compliance with plumbing codes
and/or ordinances as applicable.
STANDARDS FOR PUMPS
1. Water pumps shall have a mechanical seal, unless prohibited by code meeting the
requirements of the International Plumbing Code.
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Water Conservation Design Standards
6.0 LAUNDRY
STANDARDS FOR LAUNDRY
1. Commercial grade and residential clothes washing equipment, including coin or card operated
washers, shall meet EPA ENERGY STAR certification standards.
Project Type Current Criteria Levels
(as of February 5, 2018)
ENERGY STAR Residential Clothes Washers, Front-loading (> 2.5 cu-ft) IMEF > 2.76
IWF < 3.2
ENERGY STAR Residential Clothes Washers, Top-loading (> 2.5 cu-ft) IMEF > 2.06
IWF < 4.3
ENERGY STAR Residential Clothes Washers (< 2.5 cu-ft) IMEF > 2.07
IWF < 4.2
ENERGY STAR Commercial Clothes Washers, Front-loading IMEF > 2.20
IWF < 4.0
Source: U.S. Environmental Protection Agency, ENERGY STAR Program, 2018.
2. Clothes washers that have double dump valves and equipment of 150 pounds capacity or
greater shall be equipped so that the final rinse water can be reused in the first flush wash.
3. An economic feasibility study shall be provided to evaluate whether the use of ozone and
water reclamation systems is feasible.
4. Lint capture systems shall use dry capture or wet systems that minimize water use by only
using reclaimed or other on-site water sources.
5. Large commercial and industrial tunnel washers are not covered by specific codes and
regulations. Manufacturers shall use best practices to maintain the highest water efficiency
technology available.
7.0 FOOD SERVICE
STANDARDS FOR WAREWASHING
1. Fill and dump warewashing equipment is prohibited.
2. All warewashing equipment shall meet EPA ENERGY STAR certification standards.
3. Kitchen prerinse-spray valves shall be self-closing and shall meet the federal standards listed in the
table below. (EPA WaterSense discontinued their labeled standard for pre-rinse spray valves since
the federal standard is now ≤1.28 which matches the latest WaterSense specification.)
Table 7.1 Water and energy conservation standards for commercial prerinse-spray valves.
Product Class Maximum Flow Rate (gpm)
Product Class 1 (</=5.0 ozf) 1.00
Product Class 2 (>5.0 ozf and </=8.0 ozf) 1.20
Product Class 3 (>8.0 ozf) 1.28
Source: U.S. General Services Administration, Regulations.gov, 2016.
4. Dipper wells shall be equipped with flow restrictors and shall have a flow rate no greater
than 0.2 gpm.
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STANDARDS FOR GARBAGE DISPOSALS
1. Facilities shall consider composting as a method of food waste disposal.
2. Where food waste devices are installed, they shall meet the following requirements:
a. Pulpers and Mechanical Strainers. The make-up water use for the pulpers or mechanical
strainers shall not exceed 2 gpm. A flow restrictor shall be installed on the water supply to
limit the water flow. However, water can be recirculated within the pulper or strainer
system.
b. Food Waste Disposers. The water use for the food waste grinder shall not exceed the 8 gpm
under full load condition and 1 gpm under no-load condition. Flow restrictors shall be
installed on the water supply to limit the water flow rate to a maximum of 8 gpm. A load
sensing device shall be installed to monitor current demand and regulate water flow.
c. Time Out and Shut Off. Pulpers, mechanical strainers, and food waste disposers shall have
a time out system with push button to reactivate. The maximum allowable run time cycle
shall be 10 minutes.
d. Sink Drain Outlets. Where a strainer or basket is installed, they shall be readily
removable.
e. Strainer Baskets. Strainer (scrapper) baskets shall either fit over a sink compartment or be
attached to a drain system. The strainer baskets shall be readily removable for emptying.
STANDARDS FOR STEAMERS, STEAM TABLES AND COMBINATION OVENS
1. Steamers shall meet EPA ENERGY STAR Certification standards. Boilerless type steamers shall
consume not more than 2.0 gallons per compartment. All Boiler type steamers shall consume
not more than 1.5 gallons per pan per hour.
2. Combination ovens shall not use water in the convection mode except when utilizing a
moisture nozzle for food products in the oven. The total amount of water used by the moisture
nozzle in the convection mode shall not exceed a half a gallon per hour per oven cavity. When
operating in the steamer mode, combination ovens shall use no more than 1.5 gallons per hour
per pan.
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Water Conservation Design Standards
8.0 METERING
STANDARDS FOR METERING
1. Pursuant to Tex. Gov. Code §447.009, state agencies and institutions of higher education shall
report water usage to SECO on an annual basis by means of the Energy and Water
Management Plan (EWMP) and the Energy Star Portfolio Manager.
2. All buildings intended for daily occupation or for water-using equipment operation shall be
metered separately.
3. All meters required to be used by this Section shall be capable of remote monitoring for
data storage and reporting.
4. A separate meter or sub-meter shall be provided for the following:
a. Domestic water supply serving, all cooling towers greater than 100 tons, evaporative
cooling systems and fluid coolers installed in new buildings;
b. Any single-use or equipment that consumes more than 20 percent of the total water use at
a facility or does not produce wastewater;
c. Subtenant space greater than 50,000 square feet, or water consumption that exceeds 500
gpd, or space occupied by a commercial laundry, cleaning operation, restaurant, food
service, medical office, dental office, laboratory, beauty salon or barbershop;
d. Car washes, aquariums or equivalent projects within a building using more than 1,000 gpd;
e. Indoor and outdoor swimming pools and in-ground spas with make-up water supply
lines;
f. Make-up water to closed loop hydronic, chilled water greater than 50 tons or hot
water recirculation system used for space heating (500,000 Btuh);
g. Cold water make-up to water heating boilers of more than 500,000 Btuh;
h. Cold water make-up to steam boilers that draw more than 100,000 gallons annually or
having a capacity greater than 500,000 Btuh;
i. Make-up water supply to an evaporative cooler having an air flow exceeding 30,000
cubic feet per minute airflow;
j. Industrial processes consuming more than 1,000 gpd on average;
k. Aquaculture and fish research facilities and systems using more than 500 gallons of
potable water per day;
l. Landscape irrigation systems of 2,500 square feet or greater; and
m. All green roof systems or roof spray systems regardless of the water source.
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Water Conservation Design Standards
9.0 VEHICLE SERVICES AND WASHING
STANDARDS FOR VEHICLE SERVICES
1. New facilities shall provide secondary containment to catch spills, leaks and drips from stored
liquids and solvents.
2. Shop floors shall be sealed.
3. All hoses and water using equipment shall have auto shut-off and solenoid valves installed.
4. All facilities shall use pressure washers instead of hose-type cleaning.
STANDARDS FOR VEHICLE WASHING
1. In bay and conveyor car and large vehicle wash facilities shall be provided with equipment to
recycle and reuse at least 50 percent of the water recirculated for washing the vehicles.
2. Reject water shall be piped to a reclamation system and used for pre-soak, undercarriage,
and/or initial wash.
3. Conveyor and drive-through type washes shall use no more than 15 gallons of make-up water
per vehicle washed for automobiles, pickup trucks and small vans and shall have water
recirculation systems.
4. Conveyor and drive-through type washes shall have a flow rate no greater than 40 gallons per
vehicle washed for buses and tractor-trailer rigs.
5. Water softener recharge cycle timers are prohibited. Recharge cycles shall be controlled by
instruments that measure volume of water treated or the actual quality of the water softened.
6. Deionizing equipment shall be used for water softening instead of reverse osmosis treatment.
7. Chamois wringer faucets shall be self-closing unless the RO reject water is used for vehicle
washing in the recirculation system.
8. In-bay hand held spray wash equipment, including spray wands and foaming brushes, shall
have a flow rate no greater than 3.0 gallons per minute and shall be equipped with trigger
shut-off valves.
9. All pressure wash equipment shall be equipped with unloader valves.
10. All pressure wash equipment shall be equipped with weep holes or other devices to allow for
drainage and pressure surges.
10.0 LAB FACILITIES
STANDARDS FOR LAB FACILITES INCLUDING PHOTOGRAPHY AND MEDICAL
1. Use of Domestic water for once-through cooling / process application for any laboratory (such
as electron microscopes or rotary evaporators), medical or photographic equipment is
prohibited.
2. Lab equipment shall employ automatic control valves that allow water flow only when the
equipment is actually in use.
3. Dry hood scrubber systems shall be used where applicable. If a wet hood scrubber system must
be used, then a water recirculation system shall be equipped to the system.
4. Perchloric and fume hood wash-down systems shall be installed with self-closing valves.
5. Steam sterilizer discharge of condensate or hot water shall be fitted with water tempering
devices that blends cooler water with the discharge in order to not exceed 140 degrees F
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Water Conservation Design Standards
before it enters a sanitary waste drain. This discharge shall comply with International Plumbing
Code Chapter 8: Section 803 – Indirect/Special Wastes. The tempering water source must have
an automatic shut-off device when the temperature of the condensate or hot water discharge
of the steam sterilizer falls below 140 degrees F.
6. Steam sterilizers shall be equipped with a mechanical vacuum instead of a Venturi-type
vacuum that uses water.
7. Sterilizers shall be installed with a re-circulating cooling system or the condensate shall be
recovered for other onsite uses.
8. Dry vacuum pumps shall be used unless prohibited by local fire and safety codes that
address explosive, corrosive, or oxidative gases. Other exceptions include:
a. A teaching laboratory where aspirators are used for less than 24 hours a year; or
b. A laboratory such as a microelectronics laboratory where fumes are so corrosive that the
use of a dry vacuum pump is not feasible. In these cases, the system shall be equipped
with a water recirculation system.
9. Reverse osmosis or nano-filtration reject water shall not exceed 60 percent of feed water and
should be used as scrubber feed water or for other beneficial uses on site.
10. Digital imaging shall be used for new radiography, x-ray and photo processing.
11. All new film processor units for x-ray frames greater than six inches shall use a film processor
water-recycling unit. Units less than or equal to 6 inches is exempt.
12. Pipette washers shall use an automatic type with programmable wash/rinse cycles vs manually
operated.
11.0 POOLS, SPAS AND SPECIAL WATER FEATURES
STANDARDS FOR POOLS AND SPAS
1. Pools and spas shall be equipped with re-circulating filtration equipment and shall sub-meter
the make-up water.
2. Pools with capacity of 50,000 gallons of water or less shall use cartridge filter systems or
regenerative coated media filters. Per IGCC 2018, for filters with removable cartridges,
only reusable cartridges and systems shall be used. For filters with backwash capability,
use only pool filter equipment that includes a pressure drop gauge to determine when
the filter needs to be backwashed and a sight glass enabling the operator to determine
when to stop the backwash cycle.
3. In-ground pools with splash troughs shall drain back into the pool system.
4. Where practical, pools and spas shall be covered when not in use.
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Water Conservation Design Standards
STANDARDS FOR SPECIAL WATER FEATURES
1. Water used for start-up and make-up water in new ornamental fountains or other new
ornamental water features shall be supplied by alternative on-site water or municipally
reclaimed water delivered by the local water utility acceptable to the Authority Having
Jurisdiction. If alternative on-site water or municipally reclaimed water is not available
within 500 feet of the building project site, potable water is allowed to be used for water
features with less than 10,000-gallon capacity.
2. New ornamental fountains or other new ornamental water features greater than 3,000
gallons shall be equipped with meters and leak detection devices that shut water feature off
if a leak greater than one gallon per hour is discovered.
3. New ornamental fountains or other new ornamental water features shall be installed with a re-
circulating system
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Water Conservation Design Standards
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Water Conservation Design Standards
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