Navigating California's Water Efficient Landscape Ordinance

A well-crafted landscape design plan will help make the entire process of compliance much easier to work with - especially when developing the irrigation plan.  In this lecture I'll cover how to approach this plan in a manner that should simplify the work and plans you'll be developing further on. 

At the end of this lecture you'll have a much better understanding of how to select plants based on water conservation and adaptability to the site.

All plants have certain water needs.  In nature plant species grow where they have their requirements met - whether that be moisture, drier slopes, drainage, sun or shade - regardless of where the seed lands.  The plant is happy or it isn't. 

In our landscapes we're making those decisions.  It is critical we understand what each species wants and needs to thrive.   By grouping these plants together into hydrozones, meaning an area of the landscape having plants with similar water needs and root depths, we'll be able to manage water easier and have healthier gardens.  I'll be discussing the Water Use Classification of Landscape Species (WUCOLS IV) document that will give us much of this necessary information.

By grouping plants in this manner it will make the irrigation much easier to design and manage.

in Resources you can download a PDF of an example of how a hydrozones may be sectioned out on a landscape plan.  Actual species are not listed - just low, medium and high hydrozone areas within the landscape. 

At the end of this lecture you'll understand how to use WUCOLS IV and the Sunset Western Garden Book's Climate Zones to better select plants for your design.

Special Landscape Areas are areas of the landscape that are exempt from the water use requirements and calculations, this is what makes them special.  In this lecture I'll cover what defines these special areas.

At the end of this lecture you'll know how to identify SLA's in your landscapes.

A soil management report - or soil analysis - is required under MWELO and this means collecting soil samples and sending them to a lab for testing.  In this lecture we'll look at a typical soil analysis report, it's recommendations and discuss sampling technique.  A copy of the soil analysis is available for download.

In this short lecture I'll go over the criteria and the formula you'll need to use to calculate the maximum allowance of water that can be applied to a landscape.  Residential and commercial allowances will differ in the formula, so we'll look at both applications.

In this video I'll show how to use the updated formula for calculating the Estimated Total Water Use for your project.  At the end of this lesson you'll be able to complete the ETWU calculations for any of your irrigation designs.

Now that you know how to calculate both MAWA and ETWU let's see how to calculate the average and sitewide ETAF.

You've carefully designed a planting plan, now it's time to design the irrigation plan that will effectively water your new landscape.  There are restrictions within MWELO on how and where different applications of irrigation can be used.

Study Section 492.7 of the Ordinance and get ready for a quiz following this lecture!

At the end of this lecture you'll be confident in your ability to understand what your particular irrigation plan will require so that it will comply with the ordinance.

Knowing the precipitation rate of your irrigation system is critical to preventing runoff and proper water management.

In this lecture I'll demonstrate how to calculate precipitation rates for conventional spray irrigation

The soil management report will provide soil texture and may give you infiltration rates as well. 

In the resources for this lecture you'll find a downloadable infiltration rate chart for different soil textures and slopes as well as the formula used to calculate gross precipitation rate for your landscape. 

Once you know the precipitation rate you can adjust the irrigation run-time so runoff does not occur.

At the end of this lecture you'll know how to calculate precipitation rates of the above mentioned applications. 

Just as with conventional irrigation systems, inline irrigation will use precipitation rates for calculating your irrigation run times.  You may be surprised to see that precipitation rates for inline drip are comparable to spray irrigation rates. 

In this lecture I'll cover the formula for calculating the precipitation rate for an inline drip system.   

There's a saying - spray the turf and drip the shrubs.  Drip irrigation can have comparable precipitation rates as spray and be much more efficient.  MWELO designates how spray irrigation can be used in the landscape.  In this lecture I'll cover the restrictions of using spray as defined by the ordinance and tips on using drip irrigation - both point-source and inline drip systems.

At the end of this lecture you'll know which irrigation application you can use based on the landscape plan and the MWELO ordinance.

Reference Evapotranspiration is determined through the California Irrigation Management Information System (CIMIS).  The ETo is described as being the amount of water that both evaporates and transpires from  cool-season turfgrass, maintained at a height of 4 - 6 inches and is very well watered.

Refer to the MWELO document in Lecture One - Resources for ETo listings directly from the WELO ordinance.

At the end of this lecture you'll learn how to use the Reference Evapotranspiration Tables from Appendix A of the Model Water Efficient Landscape Ordinance for creating a weekly Irrigation Schedule for each month of the year.

Irrigation Scheduling is using ETo - our reference evapotranspiration rate - combined with the Plant Factor to determine how many minutes to run the system.  This can be on a daily or weekly rate. 

In this lecture we'll look at the process of creating a weekly irrigation schedule for both the establishment phase of a landscape and for the established landscape as well. 

Individual station run times will be determined by local watering day restrictions and soil infiltration rates so we do not allow runoff to occur.  You'll need to check with your local water agency and be aware of any local water restrictions or designated watering days.  Also, refer to your Soil Management Report for the infiltration rate of the soil to avoid runoff and determine actual run-times for your situation.

In this lecture you'll learn to use your local ETo  to calculate the number of minutes each week your irrigation should run, based on the month of the year.

Unlike conventional spray systems or inline drip irrigation, point source drip systems will use a gallons per day formula to create an irrigation schedule.  In this lecture I'll explain the Base Plant Method used in scheduling individual emitter drip systems.

No matter how well  landscape and irrigation plans are installed they have to be monitored and maintained to be efficient and reliable.  While each landscape will have its own issues, a generalized Landscape and Irrigation Maintenance Schedule will comply with most MWELO projects.  Again, contact your local Planning Dept. or other authorized agency to determine the detail they may want to see in this document.

A sample Maintenance Schedule is available for download from the Resources for this Lecture.

Once the irrigation has been installed it's time for an independent analysis - simply meaning, was the system installed per the plan?  In this short lecture I'll give a brief overview of what an audit is, what it's for and who is qualified to complete it. 

At the end of this lecture you'll know who is authorized to conduct an audit the steps to take to locate a certified irrigation auditor for your project.

While not always easy to implement, having an understanding of graywater use can save water in our landscape.  In this lecture I briefly discuss this option.  Check out the Resources for more info and educational opportunities.

At the end of this lecture you'll know the definition of both of thee terms and what constitutes graywater from a household.

In this lecture I'll cover some ways to keep stormwater on site rather than having it run off the property where there is the potential of polluting our streams and rivers.  Much of this can be accomplished when driveways and walkways are first installed, how the property is graded and what we do with water from the rooftop.  The more we can capture and infiltrate rain and irrigation water back into the soil then the less water we will potentially use.

At the end of this lecture you'll be familiar with some ways to capture rainwater on-site and the concept of the mini-watershed.

Documentation is always part of any government requirement and this is no exception.  Still, this is pretty easy to complete. In this lecture we'll look at the Certificates that need to be filled out, who fills them out and what do you do with them once they're complete.

Example Certificates will be found in the Resources section of Lecture One - within the MWELO document available for download.

At the end of this lecture you know how to complete this essential component of the process.

We've covered a lot of ground in this course - thanks so much for making it all the way through.

In this last lecture I'll offer a quick recap of what I've discussed throughout this class.  In resources you'll find more information and links to websites where you can get further information that may more directly apply to your individual situation.