March 2015

This mailer has been provided as an avenue of dispersing information related to landscape architecture in hopes of fostering greater understanding and collaboration between professions. Topics address issues that affect the built environment within which we live.
Respecting the Seriousness of California Drought Conditions
Author: Chad Kennedy, Landscape Architect, ASLA

Several weeks ago I walked the garden path of a neighbor's backyard oasis viewing an immaculately manicured landscape adorned at every corner with colorful blossoms announcing that spring had come to California. Lush plants, white noise from a water fall and a well maintained koi pond melded into an atmosphere quite unlike the surrounding Central Valley California landscape. Though quite enjoyable, I couldn't shake the uneasy feeling over how much water is required to maintain gardens like this across the State. Facing low water levels in California reservoirs and extreme drought conditions for the third year in a row, it is discomforting to observe so much water being used to maintain high water use landscapes, water over sprayed onto sidewalks by ill-designed or ill-maintained irrigation systems and irrigation systems operating when the ground is already wet from rain or fog. Though these situations still occur, California residents have actually come a long way in their awareness and respect for the value of water in the Golden State.

Public Awareness
The mid-march numbers published on the snow pack reveal how alarming the drought condition is, with a staggering state average at thirteen percent (13%) of normal.1The best option for minimizing the effects of this drought is to make significant changes in water consumption through adjustments at the individual level. Interestingly, it appears that efforts at this level to educate and raise awareness on water savings have been fairly productive. A local study was recently released reporting that 95% of residents recognize the severity of current drought conditions and more than 82% of residents now believe water conservation is important. Similarly 90% of all respondents to the study noted they would be willing to make changes "significant changes" to limit water use.3 This awareness is just the first of many steps however as laws and ordinances are now being created to govern and manage water use. In recent years the Water Efficient Landscape Ordinance and the 20x2020 Water Conservation Plan have both been enacted at the state level. This past month, the State Water Resources Control Board published additional restrictions on water. Not all of them relate to landscape water consumption, but there are a few, including two day a week watering allowances and 48 hour bans on irrigation after rain events.2 There are sure to be many more of these restrictions to come. In the meantime everyone can do their part to minimize landscape water use by examining their personal practices for irrigation and planting.

Irrigation Systems
The key to wise irrigation is efficiency! If the irrigation system is designed and installed with a focus on efficient coverage, water savings can be substantial. Unfortunately, most traditional overhead sprinkler systems will only be 60-70% efficient at best leaving a great deal of room for improvement. Below are a few ideas for improving irrigation system efficiencies and ultimately saving a lot of water.

  • Replace Spray Nozzles with High Efficiency Nozzles: There are many spray nozzles on the market now that spread water more evenly across the landscape resulting in less puddles and fewer dry spots. Some nozzles will also apply water at slower rates giving water more time to infiltrate the soil, resulting in a reduction of wasteful runoff.

  • Adjust for 100% Coverage: Spray between heads should reach each other from opposite sides of the landscape area. As distribution of water from nozzles is not equal throughout the sprayed area, this will improve coverage and eliminate dry spots.

  • Spot Irrigate When Needed: Don't run the whole system to "green up" isolated dry spots. Use a quick coupler and hose to add just a bit more water to those specific areas and you will have a healthier landscape while using less water.

  • Use Weather Based Controllers: For very reasonable up-front cost, a weather based automatic controller can be installed with most irrigation system. These controllers (in tandem with a small weather sensor) measure three crucial weather statistics in real time: temperature, solar radiation and rainfall. This data is then combined with regional historic weather data to automatically adjust watering times in an attempt to match estimated rates of water loss from the landscape (evapotranspiration). These systems are also designed to shut down watering during storms and resume when additional application of water is needed. This can be one of the most cost-effective water conservation tools available!

  • Install Point Source Irrigation: Low flow irrigation systems can be upwards of 90% efficient as the water is applied directly to the soil and root zone of the plant and not broadcast across the entire landscape. Less water is lost to wind, misting, evaporation and runoff. Most irrigation systems can be retrofitted easily with commercially available kits.

  • Install Flow Sensors and Master Valves: The simple addition of a flow sensor and a master valve on the system will halt irrigation in the event that a break or vandalism occurs within the irrigation system.

  • Perform Regular Irrigation Audits: As is the case with everything, an irrigation system needs proper maintenance to maintain efficiencies and coverages. Irrigation systems typically run during times not readily observed, often resulting in slow response times to easily fixed items such as nozzle replacement, arc adjustment and broken heads. Regular visits by certified irrigation auditors who are trained to spot areas of concern and provide recommendations for repair will return system efficiencies and avoid long-term over-application of water.

  • Schedule to Save: Scheduling watering cycles to occur between dusk and dawn is a great conservation method. Water will not evaporate as quickly at lower night time temperatures leaving more time for filtration into the soil. Additionally, splitting irrigation times into several intervals (also known as Soak Cycles) allows water to percolate into the soil gradually, reducing water runoff that otherwise might occur.

Planters and Lawns
Irrigation adjustments may be the most dramatic and immediate method of water conservation, but just as important are adjustments in planters and lawns.

  • Choose Appropriate Species: If the opportunity exists to replace plants or start fresh, plant selection can be an effective method of water conservation. Choose low water use plants (possibly, but not necessarily, native or drought tolerant). The main idea is to use as little water as possible to sustain an aesthetic landscape. There are many plants that do not require constantly moist soil in order to look amazing and flower prolifically. Choose plants that do well in the area, are hardy to the region, are matched to the pH of the soil, and are located per their solar exposure needs.

  • Install 3" of Organic Mulch: Three inches of mulch applied to the surface of planting beds will limit the amount of evaporation from the surface and will keep soils moist. As a plus, the mulch will inhibit the growth of weeds. Though inert mulches are also effective, the use of organic mulch will add nutrients to the soil as it breaks down, will hold more moisture, will improve the levels of organic material, and in turn, enhance soil buffering capacities.

  • Use Inert Materials: The use of boulders, cobbles and gravels can be an attractive way to limit the amount of living landscape requiring irrigation. Less area to irrigate equals water savings.

  • Irrigate Less (yes, it is okay!): Most landscapes are irrigated far too frequently. In most cases, trees need watering only a few times a month, shrubs once a week, and grass only a couple times a week. This may be true, however, the majority of landscapes have been trained to frequent watering routines and will need to be weaned from their dependency on shallow water availability. Slowly cut back the frequency of irrigation to stimulate downward growth of roots and the plant will perform better when infrequent watering and drier conditions occur.

  • Limit Fertilizers: Additional fertilizer, particularly on grass, causes more rapid growth and higher rates of metabolism. This requires water! Limit addition of nutrients to maintain healthy plants with as little fertilizer as possible.

Listed above are just a few suggestions for responsible use of water in the landscape. Though conditions of California drought are concerning, there is much that can, and is, being done to respect the serious situation we are in. My neighbor, despite her lush landscape, is aware of the need to conserve water and is currently planning an artificial grass replacement for her thirsty blue grass lawn. One step at a time, the battle of water conservation awareness is being won. Visit our website to read more articles, learn more about this topic, or browse information about other facets of landscape architecture.

1-California Department of Water Resurces: California Data Exchange Center. Snow Course Measurements for March 2015. Accessed March 2015.
2-Martineau, Pamela. State Board Mandates Outdoor Watering Restrictions Statewide as Drought Worsens. Association of California Water Agencies. Accessed March 2015. Updated March 17, 2015. 3-Metz, David and Curtis Below. Key findings froma recent survey on Water Conservation in California. Fairbank, Maslin, MAullin, Metz & Associates. Accessed March 2015.

Funding Opportunities

Due date: April 30, 2015

Olympic Club Foundation Grant - The Olympic Club Foundation supports and encourages participation by Bay Area youth in amateur athletics. The Foundation provides grants up to $20,000 to organizations that demonstrate the capabilities to provide high quality youth athletic programs and that have a history of achievement in those programs. The Foundation will consider capital improvements as well as equipment and program expenses so long as the grant directly benefits the youth programs. For additional information on this and other funding opportunities, please visit our resource center.

Media Updates

CPRS Conference 2015

O'Dell Engineering's Associate Landscape architect spoke with the Society for Disabilities at this year's CPRS California and Pacific Southwest Recreation & Park Training Conference in Sacramento California. The featured session title was "Recreation Programs & Resources for Special Needs." It was a fun speech on adaptive technology and recreation full of hands-on experiences and creative thinking challenges.

Project Updates

Earlimart Neighborhood Park, Earlimart, CA

O'Dell Engineering staff have just begun work on the Earlimart Neighborhood Park, a joint project between Tulare County and the Earlimart School District. This proposition 84 funded park is a long awaited project that the community has been working on for years. The team is excited to begin working on it.

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