Defining xeriscape and vegetable garden for water conservation ordinance

[Suburb Repairman]

I am revising our city's water resource management & conservation ordinance. I'm considering adding some requirements for builders to provide a xeriscape option, and to require that at least one of their model homes is xeriscaped. At the same time, I'm also working on an incentive program for converting existing yards to xeriscape. My problem is in how to define it--Xeriscape is one of those things that I know when I see it, but I'm not quite sure how to define it from a regulatory perspective. It is also complicated a bit because xeriscape varies a bit between climates & regions.

Also, we are wanting to exempt vegetable gardens from portions of our outdoor watering restrictions. Again, I find myself in a quandry of trying to define what consistutes a vegetable garden.

Some help with those definitions, along with any suggestions of places with good xeriscape conversion incentives is appreciated.

[ColoGI]

I am revising our city's water resource management & conservation ordinance. I'm considering adding some requirements for builders to provide a xeriscape option, and to require that at least one of their model homes is xeriscaped. At the same time, I'm also working on an incentive program for converting existing yards to xeriscape. My problem is in how to define it--Xeriscape is one of those things that I know when I see it, but I'm not quite sure how to define it from a regulatory perspective. It is also complicated a bit because xeriscape varies a bit between climates & regions.

Also, we are wanting to exempt vegetable gardens from portions of our outdoor watering restrictions. Again, I find myself in a quandry of trying to define what consistutes a vegetable garden.

Some help with those definitions, along with any suggestions of places with good xeriscape conversion incentives is appreciated.

Good for you.

I did that at one place where I worked and you'll want to make sure you can do the 'requirement' part before you get the department in the local paper. Surprising how knee-jerk the Realtors and some of the cheap/lazy/dumb developers can be.

Nevertheless, our fair town incentivizes turf removal/sf via the water bill and requires certain plant material goes in place. I've removed ~550 sf of turf on our parcel. I'd be happy to pass along their program paperwork via PM if you wish. Caveat: we have a tiered rate structure that makes the typical indoor use the first tier, then the second tier begins the irrigation portion, then the third tier is for the incorrigible gutter flooders. The tiered structure makes it easy to get a pricing signal - if I still had the landscape business I'd be busy 24/7 doing xeriscape conversions. Might be hard to get conversions without pricing signals or good incentives, depending on what color your county is (red-blue-purple)

I'd define xeriscape as plant material that survives with a maximum of x amount of supplemental water, be it 1/2"/wk or whatever your Co Extension Agent recommends. Usually these are natives or adapted varieties/species, and it is likely your Co Extension Agent has a list for you to build on. You'll want to ensure the conversion doesn't turn into rock, and therefore ensure that you define the conversion must be x% of live plant material, be it ground cover that covers x% after y years, or shrub canopy that covers z% after a years or whatever your PD thinks will fly. But you don't want all rock. You also want to ensure no Astroturf-type material, as it leaches certain chemicals into receiving waters and increases stormwater runoff (as well as increases urban heat island). I also think bare mulch-wood chips is OK for a while as long as plant material eventually grows over it, and is maintained at a minimum depth of x inches (whatever you can get to fly). Bare dirt not covered by at least two layers of leaves (leaf area index of at least 2) is not OK (most groundcovers meet this definition).

As far as defining veggie gardens, get some feedback from your inspectors as to their expertise so you don't make it confusing or hard to enforce. It may be as simple as 'an area behind a critter fence that is clearly dedicated to cultivation and regular food production and may contain beneficial plants' (consider that some beds may be empty to treat disease or laying fallow for some reason, making 'currently cultivated' problematic). My yard has a defined space for veggies that is a raised bed, and it may undergo periodic cultivation and contains mostly annual plants grown for food purposes. Some of my plants are to attract pollinators, trap harmful insects, and/or attract other beneficial insects such as ladybugs or wasps, so not all plants in the space are for food production. Again, your Co Extension Agent may have an appropriate definition for your area, especially if you have no critters that wander the streets looking for easy meals.

Keep at it to pass this. This is the kind of fight that you want to pick to fight and win. More power to you.

[Tarf]

Most places I work that have this sort of requirement either do so as part of a guideline (unenforceable), or they have an ordinance in place that regulates water use as part of conceptual landscape plans (and requires annoyingly detailed calculations of water consumption to demonstrate compliance).

You can see an example of one by Googling Riverside County's Ordinance 859. Hope that helps.

Edit: BTW, the above is in regards to new development. Don't have anything for you in terms of converting existing landscaping.

[wahday]

You can look at what we do in our area as far as incentives to convert existing yards here. There is a pdf link there to an approved plant list as well. The plants are listed by what area of our city they are most appropriate for as well as their water use (they use a fairly vague description of water use and don't reveal how they arrived at that, but was probably some requirement of water per unit of time).

Also, look at this page that has additional info on how they define xeriscape, what the goals of this and other programs are, etc.

The term xeriscape is derived from the Greek word xeros meaning dry, combined with landscaping, thus xeriscaping. The term was coined by the Front Range Xeriscape Task Force of the Denver Water Department in 1981. The goal of a xeriscape is to create a visually attractive landscape that uses plants selected for their water efficiency. Properly maintained, a xeriscape can easily use less than one-half the water of a traditional landscape. Once established, a xeriscape should require less maintenance than turf landscape.

We also make a distinction here between "xeriscape" and "zero-scape" which is the dreaded rock field already mentioned. While reducing water use, rock fields here add a significant amount to the heat island effect and especially to the microclimate around the home itself, resulting in increased mechanical cooling and cost to the homeowner (not to mention diminishing the range of comfortable outdoor spaces). Its already plent hot here in the summer without adding to that.

My own house is on a drip irrigation system and uses appropriate xeric plants, some of which are native, some not. Yucca, yarrow, lemon balm, rosemary, oregano, lavendar, English lace and honeysuckle are the main plants we have around the yard - its a pretty small urban lot. After becoming established, many of these plants require minimal irrigation to be healthy and vibrant. We also have 5 barrels we catch water from. THe main challeneg I find with these is that they are not connected to the automated drip system and so I tend to not take the time to manually go around with a bucket and water plants instead of using the drip. I use it for vegetable gardening, but depending on the year, that is sometimes on the drip system as well.

We also have guidelines for developers, but you would have to acccess our code to find out what they are. You can find the zone code from the main City website. Tedious, but worth it to find the language.

As something of an aside, I recently bought a book by Brad Lancaster who has pioneered the use of captured runoff. Most of his examples are from the American Southwest and its just astounding what can be achieved. When I say captured runoff here, what I mean is not catching water in containers, but using the earth itself to capture and retain runoff from roofs, streets and other hardscapes. Through the use of swales, berms, in-ground organic "sponges" and more, one can support a surprisingly lush landscape. There is a museum close to my work that has done this and even created a lovely little wetland all from natural runoff. Birds, insects, cattails and more thrive there and this in a place that can go 3-6 months without precipitation. Its pretty remarkable and I fantasize about whole cities requiring these techniques be used in all new development in drylands areas. The water savings and resulting cooling green would be truly astounding.

[dw914er]

Most places I work that have this sort of requirement either do so as part of a guideline (unenforceable), or they have an ordinance in place that regulates water use as part of conceptual landscape plans (and requires annoyingly detailed calculations of water consumption to demonstrate compliance).

You can see an example of one by Googling Riverside County's Ordinance 859. Hope that helps.

Edit: BTW, the above is in regards to new development. Don't have anything for you in terms of converting existing landscaping.

All California cities have a water conservation ordinance pursuant to AB 1881, which covers both new residential projects as well as the significant rehabilitation of yards on existing projects. Cities could either adopt the sample "Model Ordinance," or provide more strict regulations (cities such as the desert communities, or agencies under the Metropolitian Water District of Southern California did this). The list is cities and their ordinances are located here:

ftp://ftp.water.ca.gov/Model-Water-E...al-Ordinances/

The approach focuses on irrigation efficiency, which I kind of prefer. Elements such as turf can be beneficial, and if you can make your irrigation system efficient enough to have turf, then more power to you. Furthermore, if you mix the wrong grouping of plants in the wrong spot, even if they are native plants, you can still waste water. Some of the calculations though can be a bit shoddy, depending on who does them. It certainly helps to have someone on staff who is well versed on landscape and irrigation and can understand what is going on. I certainly agree that a distinction should be made in regards to xeriscape and zero-scpae. You can be water wise, and have a beautiful lawn.

However, you usually have to provide some sort of incentive for homeowners before they'll change their exisiting yards. Water rates, in general, are cheap enough that they won't bother. I've seen retail water districts team up with manufacters, (or landscape contractors, etc) to give discounted plants, weather based controllers, or rotory nozzel sprinklers, etc.