TEXAS URBAN LANDSCAPE GUIDE
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Texas AgriLife Extension Service Texas Water Development Board Texas Nursery and Landscape Association Texas AgriLife Extension Service Texas AgriLife Extension Service
A supplement to the Best Management Practices Manual produced by the Texas Water Conservation Task Force.

Appendix A
Lower Colorado River Authority
Suggested Conservation and Landscape Guidelines
With Rationale and Talking Points

  1. Landscape irrigation systems shall not be mandatory. (Many HOA’s and POA’s currently require irrigationsystems. Studies have shown a substantial increase in water use associated with automatic irrigation systems, including a 1999 City of Austin study demonstrating a 83% in water consumption in home with in-ground irrigation systems over homes without.)
  2. Landscape irrigation systems, if installed, will be required to include the
    following water conservation features:
    1. Rain and/or moisture sensors (According to Rain Bird, rain sensors can result in at least 15-20% in water
      savings.)
    2. Backflow prevention device installed in accordance with applicable state laws
    3. Pressure reducing valve and/or remote control valves for each station with flow control (Over-pressurized systems cause fogging which can result in up to 25% of water being lost to wind and evaporation)
    4. Pressure reducing valve, for which pressure reducing valve installed in-line at the meter and serving house as well as irrigation system, is acceptable.
    5. Zoning of irrigation system based on plant water requirements. (Mixing different plant types (such as turf with shrubs) in the same irrigation zone results in over or under-watering some of the plants. Because most people water for the “dry-spot,” mixed zones most often result in over-watering)
    6. Multiple cycle controllers with an irrigation water budget feature. (These controllers allow system to “cycle and soak” which decreases runoff. They also allow the system to be easily rescheduled to more closely match seasonal water needs, cutting back on water by 50% in spring and fall relative to summer application.)
    7. Minimization of overspray onto hardscapes by design, maintenance and scheduling practices. Due to overspray, subsurface drip irrigation is encouraged but not required.
    8. Low volume irrigation shall be installed in areas less than 10 feet wide, such as median strips, and parking islands.
      (Narrow areas are extremely difficult to water without overspray (and runoff) using pop-up spray heads. In addition, sprinkler heads adjacent to sidewalks and driveways are often broken or damaged by vehicle and foot traffic. Broken
      heads eliminate the potential for the area to be watered efficiently.)
  3. Contractors installing irrigation systems must provide system design plans to the homeowner. And scheduling recommendations shall be posted in or near the irrigation controller box. (Without basic information about the irrigation system, a new homeowner would have to do an extensive audit of the system to manage it efficiently. Once the pipes are covered in the ground, it becomes very difficult to understand the layout of the system without a design plan.)
  4. Irrigation systems in common areas will be monitored once a month, and any repairs shall be made in a timely manner
    (Sprinkler heads are commonly broken by mowers, pedestrians and other traffic. A system with broken heads cannot operate efficiently, and can result in thousands of gallons of runoff every time the system operates.)
  5. Spray irrigation for each home/business shall be limited to 2.5 times the foundation footprint, with a 12,000 sq foot maximum. The footprint may include both the house and the garage, but not the driveway or patio. (For every 1000 square feet that receives one inch of water (the weekly recommended amount during the summer months), about 600 gallons of water is used. That means that a 12,000 sq foot irrigated area will receive about 7200 gallons of water per week during the summer following the recommended watering schedule. Limiting the area of irrigated landscape to 2.5 times the footprint of the home allows for a more intensively landscaped area around the home without having vast irrigated areas.)
  6. Irrigated ornamental common areas at entryways and intersections shall follow the guidelines outlined below (unless irrigation of reclaimed water is necessary to meet regulatory requirements)
    1. Irrigated landscaped area shall be limited:
    • i. Subdivision entryway landscaping shall not exceed 6000 square
      feet.
    • ii. Landscaping at intersections within the subdivision shall not
      exceed 3000 square feet.
      (This allows for irrigated landscape focal points in the subdivision without vast
      irrigated common areas)
  7. Irrigation of common areas shall occur between the hours of 7:00 PM and 10:00 AM. There shall be NO WATERING between the hours of 10:00 AM and 7:00 PM unless irrigation of reclaimed water during the day is necessary to meet
    regulatory requirements. (Watering between dusk and dawn reduces loss to evaporation which can be as high as 40% during the heat of summer.)
  8. All irrigated and newly planted turf areas will have a minimum soil depth of 6 to 8 inches. Builders and owners will import soil if needed to achieve sufficient soil depth. Soil in these areas may be either native soil from the site or imported, improved soil. Improved soil will be a mix of no less than twenty percent compost blended with sand and loam. Caliche shall not be considered as soil. (In the turf type used in central Texas, the majority of roots grow in the top 4-6 inches of soil. A recent study conducted by TAMU and SAWS tested the drought tolerance of the main turf types during 60 days without water on 4 inches of soil and on unlimited soil depth. All of the turf planted on 4 inches of soil died during the 60 days without water. On deep soil, all of the turf rebounded except some varieties of St. Augustine, demonstrating the importance of soil depth on turf survival and health. Additionally, according to the Irrigation Association, up to a 50% water savings can be achieved by increasing soil depth for a turf area from four inches to eight inches. Compost increases the water holding capacity of soil by about 16,000 gallons per acre foot for each 1% organic matter. This decreases runoff and improves plant health.)
  9. Native soil shall be stockpiled and reused on site.
  10. Topsoil that is added to the site shall be incorporated in a 2 to 3 inch scarified transition layer to improve drainage.
  11. In new homes, no more than fifty percent of the landscape may be planted in turf. (Turf is the most watered component of the landscape. Limiting turf area reduces outdoor water use.)
  12. All new turfgrass installed shall have summer dormancy capabilities. (Turf with summer dormancy capabilities insures that landscapes will survive under mandatory water restrictions.)
  13. Shrubs and flowers should be selected from native and adapted plant list approved by the LCRA or _________ County/City. (Using native and well adapted plants in the landscape reduces the need for supplemental
    water and chemicals.)
  14. Invasive plants listed in this document shall not be used. (“Problems caused by invasive plants cost billions to the global economy every year, mainly from loss of grazing land and reduced crop productivity due to non-native weeds. The cost to the United States alone is an estimated $137 billion a year in management and missed economic gain. Ecologically, they can disrupt ecosystem services and disrupt communities by being spacedominant or through impacts on keystone native species. At their worst, invasive plants have the ability to degrade whole ecosystems, both terrestrial and aquatic.” Source: Wikipedia)
  15. Landscape companies providing maintenance on all common areas and individual landscapes must only use integrated pest management (IPM) to minimize exposure of storm water runoff to chemicals (fertilizers, herbicides and
    pesticides). IPM prohibits routine and “preventive” broadcast application of broad-sprectrum chemical pesticides in the absence of evidence of active pests. IPM techniques include the following:
    1. Accurately identify pest or disease problem before considering treatment
    2. Explore cultural or mechanical controls (i.e. modification of irrigation, pruning, etc)
    3. Look for biological control options (i.e. predatory insects for pest control, Bt for caterpillar control, etc)
    4. Consider chemical control only if other options fail
    5. Utilize least-toxic and targeted chemical controls
    6. Baits are preferable to broad-spectrum chemical application
    7. Follow instructions on chemical labels exactly
    8. Perform periodic monitoring for early detection of potential problems
  16. Landscape companies providing maintenance on all common areas and individual landscapes must only use the following fertilizer practices:
    1. Fertilization of turf areas shall not be required
    2. In turf areas that are to be fertilized, natural or certified organic fertilizers with less than 4% phosphorus shall be used.
    3. Fertilizer shall be applied at a rate of ½ pound of nitrogen per 1000 square feet, not to exceed a total of one pound of nitrogen per 1000 square feet per year. (Phosphorus accumulates in alkaline Central Texas soils, and there is generally not a need to add large amounts of phosphorus in the form of fertilizer. Nitrogen is limited in Central Texas soils and does not accumulate. Although adding small amounts of nitrogen can be beneficial to plants, excess soluble nitrogen runs off or leaches through the soil as a potential pollutant to ground and surface water.)
  17. Builders or property managers must present guidelines for IPM plans and fertilizer practices meeting the deed restriction requirements to home buyers at the time of closing. (These guidelines are contained in Grow Green fact sheets available from LCRA)
  18. As passed by HB 645 in the 2003 Texas Legislative session, the homeowners or property owners association documents (including declaration of covenants, articles of incorporation, bylaws, or any other document of the association which binds members of the association) shall not restrict the property owner from:
    1. implementing measures promoting solid-waste composting of vegetation, including grass clippings, leaves or brush, or leaving grass clippings uncollected on grass;
    2. installing rain barrels or a rainwater harvesting system; or
    3. implementing efficient irrigation systems, including underground drip or other drip systems.
  19. The homeowners or property owners association documents (including declaration of covenants, articles of incorporation, bylaws, or any other document of the association which binds members of the association) shall not
    require:
    1. a defined irrigation schedule specified by the association except if that defined irrigation schedule is mandated by the association’s water supplier in order to curtail outdoor water use.
    2. maintenance of the landscape to a specified level that requires the property owner to irrigate his or her landscape.
    3. installation or maintenance any specific variety or limited choice of varieties of turf grass.
    4. the homeowner to install a minimum percentage of turf in the landscape. (Homeowner association rules should not be in conflict with water conservation measures)
  20. A minimum of two inches of mulch shall be maintained in all shrub and bed areas. (Mulch helps retain soil moisture, moderated soil temperatures, and helps prevent soil erosion)
  21. Encourage rainwater gutters sized appropriately to catch rainwater from the rooftop.
  22. Encourages galvanized metal roofs to facilitate rainwater storage.
  23. Encourage installation of water efficient toilets, dishwashers and clothes washers.
  24. Encourage incorporation of treated effluent/rain water/storm water systems to meet certain irrigation water needs, including common areas.