Tucson's Green Stormwater Infrastructure: An Example to Other Cities

Tucson is known for many things: the heat, delicious Mexican food, lovely winters that attract snowbirds (and other birds), outdoor recreation, ranking 48th in school funding, and our friendly small town feel. We have a lot to be proud of too - from our biking trails (the Loop rocks!) to our City of Gastronomy designation.  It may surprise you that Tucson is also known for our innovative water programs. Tucson far surpasses Phoenix in water conservation and rainwater harvesting installations. Our Green Stormwater Infrastructure (GSI) program is still fairly new, yet it is already gaining a reputation as an example for other arid cities. 

Brad Lancaster (who installed the first guerilla curb cuts in the now lush Dunbar-Spring neighborhood) has become a world renowned water harvesting champion. Brad and other water harvesting enthusiasts, including Watershed Management Group, advocated for the city's Green Infrastructure program. On September 4, 2019 the Mayor and Council approved the GSI Program Proposal!

GSI is any constructed landscaping feature that uses stormwater in combination with natural processes to perform ecological services. Those services include managing stormwater (to prevent flood damage), using rainwater to support shade trees and other desert plants to cool our city streets, create a habitat for desert critters and sequester carbon to fight climate change.  

It is recommended that Green Stormwater Infrastructure be installed to irrigate many of the trees that are being planted as a part of Mayor Romero's #Tucson Million Trees program.  

You may have noticed curb cuts directing street water into right of way basins with native plants...

properly maintained right of way basin

Unfortunately, not all GSI installations are good examples.  A series of basins constructed on Stone Avenue had palo verde trees that fell over because they were planted in the bottom of the basin and got root rot. Live and learn. One of the first principles of rainwater harvesting is to observe how the system works and then adjust accordingly.

You may have seen some unsightly basins filled with trash and weeds. One of the issues with the basins is they need to be maintained. They tend to collect trash and invasive weeds like buffel or bermuda grass that block the entrance of the basin and prevent it from working properly.  

A group of water professionals and citizens learn how to monitor GSI

The city is aware and is making strides in correcting the issue. On May 1, 2020, a new Green Stormwater Infrastructure fee was included on utility service statements for residents and businesses within the City of Tucson.

The city's new GSI Program will:

*Provide a funding source for maintaining hundreds of existing GSI features in city neighborhoods
*Support growing more trees and plants on streets, and in parks and public areas using stormwater as a primary water source
*Address and reduce flooding issues on neighborhood streets
*Put rain/stormwater runoff to beneficial use irrigating plants
*Reduce stormwater pollution
*Shade and cool streets, sidewalks, bikeways, and parking areas
*Beautify neighborhoods
*Provide an affordable alternative to building and maintaining expensive underground stormwater infrastructure*

This fee is assessed based on customers’ water use at a rate of 13 cents per Ccf (about $1 per month for the average residential customer), and will raise about $3 million each year to build and maintain projects throughout the city that capture stormwater runoff from public streets and parking lots, and divert it into vegetated water harvesting areas. These kinds of projects are called green stormwater infrastructure, or GSI.

As I mentioned, one of the first principles of rainwater harvesting is to observe how the system works and then adjust accordingly. The city's new GSI system is no exception. There have been some incidents in which city maintenance workers (some outside contractors) weren't aware of how GSI systems work and have unwittingly harmed the system by removing vital native vegetation or over-pruning desert trees. This is very frustrating and disheartening for those who worked hard to install or maintain the systems.

I have attended Low Impact Development (LID) meetings where these issues have been discussed. The city reps listened to our concerns and are doing what they can to solve them. They are working on solutions that include setting up a monitoring system and implementing training for maintenance workers. Dan and I recently participated in both.

Here we are learning how to use the monitoring app on our cell phones.

 

The apps were used to record the type of water harvesting feature (in this case traffic calming chicanes), inflow and outflow, whether or not the inflow is obstructed with sediment, materials it is made out of (rocks or mulch), the kind of vegetation, invasive weeds, if it needs maintenance.  There was also a place to post pics. 

Dan took lots of pictures including this chicane that was overgrown with bermuda grass. 

While Dan was busy taking pics,  I went ahead and picked up some trash. I felt that if we want to be a good example we need to leave the neighborhood better than we found it.  

Dan and I spotted a lot of invasive buffel grass in the basins. I didn't want it to spread throughout the neighborhood, so I decided to pick what I could out by the roots. It was pretty easy to pull out in the soft basin soil. I was careful not to let the seeds disperse since that would totally defeat the purpose, right? So I carefully broke off the stem below them (see pic below) and placed the seeds in a plastic bag I found nearby. Then I sealed the bag tight so they won't fly out when the trash truck picks it up. 

If you decide to do this kind of work, it's recommended that you wear protective clothing like closed toed shoes, a shade hat, light weight long sleeve shirt, long pants, and gloves. (I know. I know. I didn't. But I wish I had.)  Also be mindful of your surroundings, especially traffic. 

While we were checking out one basin, I got a nice surprise. I found some volunteer sorghum. I went ahead and gleaned the seeds to plant in our greywater basin. We've found that sorghum (from the birdseed the squirrels planted in our yard) helps the water to infiltrate better. Not to mention...the birds like it! 

It was great seeing city and county employees (including those from Tucson Water) who had rallied for Green Infrastructure join interested citizens (like me and Dan) on a Saturday morning to see how our green infrastructure is doing.  They really do care! 

And they didn't just leave it there.  After recording the needs of the GSI, the city held excellent maintenance training that included how it works, how to identify useful native plants vs. invasive, and how to properly prune (or not prune) desert trees.  Attendees included city workers, landscapers, U of A maintenance personnel and even some interested parties from New Mexico and Mexico! 

Makes me proud to be a Tucsonan! 

More Information: 

For the Love of Tucson: Creating a Desert Oasis to Combat Climate Change

Horse Purslane Mulch

horse purslane provides living and dry mulch for our yard 

You might remember how our yard transformed into a "glorious habitat for pollinators" after the abundant rain this summer. While some people might call them weeds, we were delighted to have this patch of horse purslane as living mulch to slow down the water (preventing erosion) and allow the water to sink in while nourishing the soil. Our edible forest flourished. Our moringa trees grew crazy big and our jujube produced more fruit than we could eat! 

I pulled out the purslane along our path so it would look intentional.  It's super easy to pull!  

Neighbors complimented us on how lovely our yard looked. 

pile of pulled purslane 

If you pull it before it goes to seed, it makes good compost too - especially if you have a hot compost pile that kills any remaining seeds.  

When the pile started to get brown I broke it up into small pieces to replace the wood chip mulch that was decomposing in our basin. Free mulch! 

The rest of the purslane morphed to burgundy with the season.  

Instead of seeing the beauty in the new shade, I worried what the neighbors might think about it -  especially the purslane that the ants got to. It looked pretty weird without its leaves. So I decided to cut it up into mulch too.

In retrospect, I may have jumped the gun.  I heard that some farmers in Wilcox were using purslane as a cover crop. So I googled, "What does purslane add to the soil?

Purslane grows close to the ground and spreads out to create a thick mat that suppresses other weeds and helps to keep the soil cool and moist. This living mulch can be a great benefit to the garden but also it must be managed.

I guess it would have been better for the soil to leave it in until the roots decomposed into organic matter. After learning that, I waited until the purslane dried up before breaking it into smaller pieces.

Notice the red horse purslane in the foreground and the dried straw-like mulch in the background...

At one Master Gardeners presentation, they mentioned that we don't have a lot of organic matter in our desert soil. Is it any wonder when we dig out all the native plants (weeds), rake up the leaves, and even use Roundup that kills the weeds, the soil, the insects and microbes in it. I hope that one day we learn to value our health and healthy soil above superficial "appearances."

A few years ago, I spent weeks pulling Bermuda grass and invasive Russian Thistle out of the alleyway to make room for edible weeds. I dubbed it my "Alleyway Buffet." So I was happy with the patch of horse purslane that become a habitat for butterflies and other pollinators. I watched in awe as the birds swept down to nosh on the purslane seeds. 

alleyway and the area of our future 3 Sisters Garden

Imagine my shock when I caught a neighbor spraying Roundup in the alleyway behind his house - right across from the children's playground and our 3 Sisters Garden. If he had just waited, it would have dried on it's own in a week or so. I would have been happy to use it as mulch! Instead it's going into the landfill.   

Here I am raking up the poisoned horse purslane (including some in our 3 Sisters Garden where the Roundup had spread when it rained... ) We asked the neighbor if we could spread some gravel that was under our eucalyptus tree behind his yard as a natural weed repellent.

Meanwhile, our front yard basin is covered with a bed of free organic horse purslane mulch. I can't wait to see how it keeps the moisture in the ground when it rains and then breaks up into organic matter for the soil. 

More Information: 

Is Purslane a Friend or Foe of the Garden?

Why We Love Our "Weeds"

When we came home after an 11 day vacation we were amazed how all that rainwater had transformed our front yard into a glorious habitat for pollinators and birds as well as a productive edible forest! 

The moringa trees  in the street side basin were HUGE - even the one that we thought had died in the freeze.

native trees: acacia and desert hackberry 

Our native trees - that we didn't water during the excessive heat warning -  had not only survived but were full and leafy.

The desert hackberry had lots of berries on it for the first time ever.

The small jujubes in another basin were twice their size and the big one was loaded with fruit, some of it ripe and ready to enjoy!  

The whole yard was covered by beautiful horse purslane and native grasses. (I had long since eradicated all the goat heads and other sticker weeds.)   I was concerned that some neighbors with gravel covered yards might call it a "jungle" overgrown with weeds. So the next day I was out there pulling the purslane and the poisonous spurge covering our walking trail.   I wanted to send a message to the neighbors that we had left those weeds there on purpose. I also uncovered some decorative cactuses and wild flowers. I pulled any weeds that were encroaching on the neighbor's yard or on the sidewalk. We try to be good neighbors. 

While I was out there, I saw pollinators flying around (lots of butterflies, a spectacular moth, wasps, and ants.) As I pulled out some yellowing purslane, I discovered a caterpillar on there. 

It was loving the purslane. When I was pulling out the spurge, I saw a trail of little ants going after it. I considered leaving it for them. After all...isn't it better to have them go after spurge than my trees? 

I inspected the soil under the purslane by the butterfly bush and I found a little caterpillar and the mushrooms! I was pleased to see that the weeds were nourishing the soil!

Just when I finished posting the caterpillar pic, a storm raged in. 

This development changed the direction of my story from the frustration I felt when two neighbors sprayed roundup this afternoon. Though I did watch water flow from one of the sprayed areas into the little patch of land where Dan likes to plant a three sisters garden.

And rain from the yard pictured on the left flows all the way down the street to the median where Dan wants to organize a neighborhood garden. The landscaper got the Roundup sprayed just in time to share it with the whole neighborhood. Yeah, yeah...I had to say something. 

But I'm excited to transition to a happier ending.  Documenting the effects of the raging storm on our catchment basins is a great chance to show how the native grasses and horse purslane help prevent flood damage. Check it out! 

See how the native grasses slow down the water to prevent erosion and hold in the water in our street-side basin that is home to our precious moringa trees. 

This picture shows how the native grasses slow down the roof water rushing from the downspout before it hits the smallest jujube tree. Then the horse purslane slows down and sinks in the water before it hits the last two trees. Those so called weeds help nourish the soil and attract pollinators to the flowering trees.

Clearing out the horse purslane on the path allows us to see how the water pools in around the path and then how well it sinks in soon after the rain stops. Dan dug the shallow basin so it slows down, spreads out and sinks in the water (a rainwater harvesting principle). The native grasses and purslane help it slow down and sink in too! 

So you can see why Dan and I love our "weeds." They help to make our basin work properly. And we think they are beautiful. 

Sustainable Maui?

We just got back from a lovely, regenerative vacation on Maui to attend my niece's wedding. Dan and I enjoyed learning about what Hawaiians were doing to become more sustainable and their efforts to restore the island using traditional methods. We took pictures of the massive Banyan Tree planted in 1873 and read about the history of the island at the Lahaina Courthouse Museum. We were delighted to learn how their traditional food systems worked with nature. On an awe-inspiring tour of the King's Garden and waterfall, we saw how they grew the different foods on terraces that climbed the mountain. But my most cherished moments were the quality time we spent with family members we hadn't seen for some time, especially the heartfelt talks with my little sister and mom that ended in tears and warm hugs. 

Since we got back, I have been struggling about whether or not to write this blog. To be honest, I feel guilty. I'm not sure I come across that good in this story. When I heard that most of my family was heading to Maui to attend the wedding, I didn't want to miss out on seeing them. I overlooked my fear of traveling with only a cloth mask to protect me from the dreaded new variant of COVID. (I was somewhat reassured since we had to register proof of vaccination on the Hawaii Safe Travel Pre-clearance app.) But the day after we purchased our tickets to Maui, I saw a post from a Facebook friend musing about why so many of her friends were posting pics of themselves in Hawaii when the Mayor of Maui had issued a statement asking visitors to stay away. 

When we got to Maui, we discovered another motive besides COVID. The Mayor was trying to protect the island. A record number of visitors were escaping the confinement of COVID on this island paradise. A quarter of a million every month!  The streets were crowded with rental cars. Dan said that it reminded him of LA! During our 10-day stay we became increasingly concerned with the environmental impact on the island. 

We had indulged in the privilege that allows those of us who can afford it to have an "experience of a lifetime" at the expense of the sea creatures and reefs. One young man, bobbing in the water next to us, shared what he learned on a his turtle island tour - that you shouldn't disturb or touch the endangered turtles, and then proceeded to grab at a turtle that swam by. 

I know. I know. We were keenly aware that our presence negatively impacted the island (from the pollution and CO2 on the long plane ride, our Lyft to and from the airport, and the diesel-powered snorkeling and wedding boats.) Dan and I did what we could to lessen our impact.  We chose not to rent a car.  We got a senior discount on a pass for the bus and used it. We even rode the bus to the thrift store to get Hawaiian shirts and dresses for ourselves and some family members. On the bus, we went by several sea-bird restoration areas.  

On our first day there, we discovered a cool restoration trail where we learned about how the island in the distance, Kaho'olawe, was a sacred place to the Hawaiians, once used for navigation training. The island people developed an innovative and sustainable lifestyle of fishing and farming. But outsiders brought too many sheep and goats that destroyed the soil with over-grazing. Then the U.S. conducted their bomb tests on the island. Signs showed how the Hawaiian people are restoring the preserve by planting native grasses. 

Kaho'olawe Educational Walking Trail

We were shocked by the amount of trash along the nature trail. We picked up what we could. But it got us thinking. Where was all the trash going? How much of it ended up going out to sea? We saw recycling bins all over the island and signs asking people to consider reducing their plastic consumption. A sign along the highway read, "Landfill full." We were concerned about adding to the trash on the island. So we carried reusable grocery bags and water bottles, and brewed our own tea (instead of buying the bottled variety.) My sister, bless her heart, was doing her best to recycle - unaware that it wasn't all recyclable in Maui. (They only recycle two kinds of plastic bottles.) Dan helped her out by looking up the website on his phone.

There were also signs warning people of the impact of sunscreen on the reefs. So we wore tee-shirts over our swim suits and I used "reef safe sunscreen." (Dan burned.) During the family snorkeling outing, we saw the impact of all those visitors on the reefs in the Marine Life Conservation Area. These were not the colorful reefs we saw at the aquarium. These reefs were gray and dying. Dan started calling our vacation, "The Environmental Disaster Tour of Maui." 

There were several other boats at the Marine Life Conservation Area

Despite efforts to educate the public with signs and displays, the impact of the tourism industry was clear. The side of the island where we were staying is actually a desert. But they have planted tropical trees and flowers to create a paradise for the resorts, using up the island's groundwater (that the farmers on the other side of the island rely on.)  Everyday, shiploads of consumer products are unloaded in the harbor. And planes bring more tourists. Rental cars line the shorelines and scenic routes. Perhaps the best thing we can do to heal the island is follow the Mayor's advice, and stay away. Give their restoration efforts a chance. 

There is a glimmer of hope. In addition to restoration projects, they are installing some sustainable  infrastructure. There are plans for a fleet of electric rental cars and charging stations. Some of the hotels and houses have solar panels and wind turbines line one of the mountains. A solar farm shines in the distance. 

We are thankful for the opportunity to enjoy my family on this beautiful island and learn about important work being done there. We feel a sense of responsibility to the native Hawaiians, so we won't be returning to the islands any time soon. We want to ensure they don't become a paradise lost.

Mahalo Maui! Aloha and blessings on this island in the sun. And congrats to Alexa and Clayton! 

More Information: 

Application of Traditional Ecological Knowledge and Practices of Indigenous Hawaiians to the Revegetation of Kaho‘olawe.

Will Hawai‘i Show the Rest of the Nation the Way to Clean Up the Power Sector?

Maui Launches Stainless-Steel, Zero-Waste To-Go Container Program 

Lessons from the Rain: Connecting with Our Neighbors

I recently posted a pic of the gutters and downspout Dan installed on our neighbor's overhang pouring rainwater into our new cistern. The overwhelming response on Facebook was, "Good neighbors!" And Dave certainly is a good neighbor. But it was also mutually beneficial. Directing that water into the cistern prevented unwanted erosion in his yard. This story not only illustrates the importance of having a good relationship with your neighbors, but also how interconnected we are. 

Nature knows no boundaries. What grows in the neighbors' yard, may end up in ours. This morning I found a branch with pine cones on our side of the fence. We don't have a pine tree. But I benefited by using the pine needles in our compost pit! (If only we could replace our eucalyptus tree with a tree that would drop leaves that would nourish the soil. )

Last night, a gust of wind dropped a branch from our eucalyptus tree onto our neighbor's roof. They say good fences make good neighbors. But if you have one of those "widow makers" it's better to have open communication with your neighbor! A friend shared how his neighbors got mad because he took out a tree that shaded their yard. So we discussed the tree situation with our neighbors over the fence. 

A big downpour (not to mention birds) also spreads seeds. Weeds don't stop on the property line. If allowed to go to seed, they will spread throughout the neighborhood. That's why I sometimes venture into my neighbor's yard and pull out the sticker weeds. And Dave always thanks me.

I recently pulled the native grass that lines Dave's sidewalk and replanted it in our street-side catchment basin. Again, it's mutually beneficial.  (The roots of the native grass work with the woodchip mulch to create a sponge to hold the water longer. The grass also helps prevent erosion from big storms.) 

There is a right of way on our block that is covered with highly flammable, invasive buffelgrass. Just after it rains, I have been known to get out there with my little shovel and pull up what I can by the roots before they go to seed and spread throughout the neighborhood. If I see one popping up in someone's right of way, I simply bend down and pull it out. It's good exercise.

buffelgrass 

My husband likes to call me "The Crazy Weed Lady." Not sure if that has caught on with the other neighbors yet. They might be calling me "Annoying Moringa Woman" or "Edible Weed Gal" or "Water Schlepper."  Anyone who walks their dog past our house may be privy to an unsolicited lecture on the benefits of our rainwater harvesting basins or get a taste of the moringa or purslane growing in our yard. Sure, this might be annoying for some, but others have caught on and implemented rainwater harvesting in their own yards. One neighbor even planted some of our purslane seeds in her yard. I think it's worth it.  

I hope my lessons on edible weeds have kept some people from spraying Roundup. The herbicide some people spray all over their right of way doesn't just stay in their yards either. It is washed down the street in the rain. It sinks into the ground. Roundup has been detected in aquifers! That's a problem because, here in Tucson, we store our drinking water in our aquifer. The aquifer is only 5-8 feet below property near rivers. Watershed Management Group encourages people near rivers to put catchment basins in their yards to replenish the aquifer. 

Rainwater doesn't always stay in one yard either. It often runs into the street or even into a neighbor's yard causing erosion and damage to the foundation of houses. But we can put in catchment basins to slow down, spread out and sink in that water in our yard to use on our native landscaping. If your street is at the bottom of the watershed, neighbors can work together to put in street-side green infrastructure to protect and shade the neighborhood.

We can have beautiful, cooler, green neighborhoods. We just need to take a lesson from the rain and connect with our neighbors. 

Before and After the Rain

Last night we celebrated the long awaited rain by taking a lot of pictures. 

There is always some preparation for monsoon season: clearing debris from the gutters to the cistern, adding more mulch to basins, and  making sure that nothing is obstructing the earthwork channels that direct water to the hummingbird trumpets. 

But this year we have had to deal with the effect of extreme heat followed by flooding on our landscape. A couple weeks ago, a "Tree Stress" alert was issued. We were encouraged to deep water all our trees to survive the excessive heat. Dan was shocked by how much water we used. 

That was followed by a "Flash Flood" warning. And down it came with a fury!

One thing I learned was that I could have held off on deep watering my native trees. I also learned that every drop of water is precious! 

Luckily Dan had already installed a small cistern to harvest the water from our generous neighbor's roof. Thanks, Dave!  . 

It was a delight to see it working well.

Dan tried to get in another cistern before last night's storm. But he only managed to get in the gutters before the downpour started. 

So he grabbed every bucket and pan he could find to catch the water rushing from the downspout. 

This was quite the gully washer! Our new cistern and the blue water barrels filled up.  It filled up our greywater basin...

Our right of way basin was quickly filling up...

Our jujube basin started overflowing...

No worry about mosquitoes... The water in all the basins sunk in beautifully (as planned) by morning! 

After seeing the effects of extreme heat on our plants, we learned that every drop of water counts.  I've gotten in the habit of checking the weather each morning to see if it is going to rain. I try to use up the water in our buckets before the next downpour. I don't want to leave water in the buckets long enough for mosquitos to lay their eggs in there anyway. 

But where to put the water?  

I used my favorite water bucket to deep water my garden and the jujubees (alternating between them so the water could have a chance to sink in and not cause erosion.) A few of the buckets had lids so I left them for later (in case it doesn't rain.) Dan is in the process of installing a bigger cisterns that won't need to be completely emptied before the next rain.  Thank heavens!  All this bucket schlepping is killing me! 

While I was out there, I also did a little damage control.  I made sure that the mulch was three inches away from the trunks of the trees so termites didn't get them. I was  careful not to disturb the white stuff (mycelium) that means that the soil is healthy.  I was also happy to see the little mushrooms around the big jujubee (that also means that soil is good.) Wow! The soil sure loves the rain! 

Checkout how these tiny "weeds" kept the mulch from washing out of the basin! The native grasses that lined our right of way basin also slowed down the storm water to prevent erosion!

The roots of the native grasses and other desert plants work with the wood chip mulch to create a sponge to hold the water longer.  These so-called weeds are a vital part of our earthworks! 

Now we're ready and looking forward to more rain! 

After more rain this happened.