Lithohydrology: The art and science of moving water through a landscape using dry laid stone work.

Andrea Hurd • May 17, 2023

LITHOHYDROLOGY

Harvesting water through the use of dry laid stone work​



Lithology-- Definition according to Merriam-Webster dictionary:

the study of rocks

the character of a rock formation


Hydrology-- Definition according to Merriam-Webster dictionary:

a science dealing with the properties, distribution, and circulation of water on and below the earth's surface and in the atmosphere

A stone wall surrounded by flowers and plants in a garden.

It’s all in the Design


Understanding the way nature works is the guiding principle for our designs at Mariposa. Our design team considers multiple ways to replicate natural ecological systems in your garden.


One of the ways we use our understanding of natural systems is through the designing and building of garden features out of stone. Our stone features are durable and they are also permeable. We do not use mortar to bind our stonework, rather we employ techniques to build walls, patios and paths that have been proven over centuries to be durable. Dry laid stone work allows water to move through stone structures. Our techniques with stone give us the ability to slow, spread and sink in our gardens to make sure that the water that falls in your garden, stays in your garden.

A wooden fence is surrounded by gravel and a brick walkway.

Water is a resource, not a waste source​


Conventional wisdom dictates that rainwater falling on a roof and property, must be removed away from the property in order to not cause damage to the house foundation. Most often, water is routed out into the street through downspouts from the roof and underground french drains. Downspouts and french drains channel rainwater to a point off of the property, most often routing it into the streets where the water gathers pollution before it enters a storm drain. Storm drain water eventually is delivered into an existing river or creek or into the Bay in the Bay Area. This water is not well suited for natural ecosystems as it introduces unwanted pollution.

A garden being built with bricks , rocks and plants.

Removing the water that would naturally fall on a property is a way of protecting a house from water damage. This action makes the water a source of waste that homeowners feel the need to protect their property from. However, especially during a drought, we see this water as a resource that can be used and stored on the property to keep the plants green and thriving.

With thoughtful design and intentional building techniques, we use stones to move water away from foundations and keep it in the landscape. This is especially important to do in the drought to replenish the groundwater table.

A pile of rocks is sitting on top of a pile of dirt.

Slow it, sink it, spread it​


At Mariposa we build stone features, such as walls, on a foundation filled with drain rock and decorative gravel. This feature is called a "footer" as it is at least one foot deep. A footer can slope in one direction or another, depending on how we want water to move in the landscape. This construction allows us to move, collect and store rainwater in the ground. The drain rock allows the water to gradually move under the ground, away from foundations, houses and other structures that may be damaged by water, slowly sinking into the soil as it goes. When we design our gardens, we are thinking about where to locate our stone features often based on how we want water to move through a property.

A man is kneeling down in front of a pile of wood.
A house is sitting on top of a hill surrounded by trees.

Grading the landscape with dry laid stone features​

We construct stone hardscape features such as dry stacked stone walls and dry laid paths and patios with natural construction methods that are both ecologically friendly and create ways to move water to where we want it in the landscape. Dry laid stone walls have “footers” which are essentially trenches filled with drain rock. Paths and patios are similarly constructed, in that they have a 6' base of drain rock and decorative gravel, allowing them to further slow, sink and spread water.

A person is digging in the dirt in front of a house.

The pan grade, which is the native soil after existing concrete or plants are removed, is graded by hand so that water flows away from the foundation of the house at a slope of at least 2%. Dry laid paths and patios are constructed on top of 3” of drain rock with 3” of decorative gravel above that. The drainage material under the flagstone helps to set the stones in place while allowing water to percolate into the rock and soil below at a rate that avoids puddling or flooding.

A stone patio is being built in front of a house.
By Andrea andrea June 9, 2025
CHECK YOUR SOIL! Isn’t it great to feel the longer and warmer days of late Spring? I love the feeling of going outside and seeing the sun, shining brightly on all of the green leaves and beautiful flowers. It is so wonderful to feel the glow of summer approaching. What a joy to get caught up in that glow, while we watch the gardens grow gorgeously. However, that joy makes it easy to forget that here in the Bay Area, we are entering the months long dry season. Our Mediterranean climate shifts this time of year, which can transform gardens from showing lots of flowering and new green growth, to gardens where soils and plants become dry and damaged. This transition can lead to health issues in the garden over the coming weeks and months. While plants are still thriving from the lovely winter rains, the soils are now drying out. We often don’t realize that the soils are becoming too dry because at this time of year, it takes plants longer to show signs of stress. However, if we know what is about to come, we can stay ahead of the dry season and the damage that hydrophobic soils can do to our garden.
By Andrea andrea May 3, 2025
With the warmer temperatures and longer days, gardens are literally bursting with hope. New leaves unfurl and early blooms emerge under the lengthening days and warming temperatures. April never fails to inspire me with its magical expression in the natural world. Each year, as this phenomenon occurs, I am delighted by the immense force that nature has to replenish and re-emerge anew. Being able to count on the small miracles of leafing out and blooming helps to give stability in an unstable world. Tending a garden is not only therapeutic for our soul, but also will help heal your local environment.
By Andrea andrea April 28, 2025
Spring is an amazing time of year to witness rebirth and transformation in the garden. Buds are swelling, flowers are beginning to bloom and butterflies are starting the procession of early, mid and late seasonal emergence into the garden! All of the subtle and beautiful change that happens day to day draws us gardeners out into the garden to witness the fullness of spring. During March, we see a chorus of changes in the garden, each element playing in harmony. Paying close attention to how your garden is changing and developing during this season can help you to become a better guardian for habitat protection. In Mariposa’s newsletters and articles , we discuss that in order to protect habitat in the winter garden, one must be very careful. Many grown pollinators and butterflies, as well as their dormant eggs gather protection under the leaves and in the dried stems of flowering perennials such as Echinacea (purple coneflower) and Rudbeckia (black eyed Susan).
By Andrea andrea January 11, 2025
How to cultivate life in your garden and provide more habitat for pollinators!
A bunch of orange flowers are growing in a field.
By Andrea Hurd September 18, 2024
As the reality of climate change looms larger, the need for individual action becomes imperative. Our weather is growing hotter, rain patterns are erratic, and fires across the Western US are increasingly more destructive.
A bunch of pink flowers are growing in the grass.
By Andrea Hurd September 12, 2024
Gardening connects us to nature. It also invites us to think like scientists. The garden is our laboratory where experimentation, observation, and evaluation are a part of the process. ​
Two women are standing next to each other holding a certificate.
By Janet Richardson June 21, 2024
We're so excited to announce that we won the California Landscape Contractors Association 2023 Beautification Award for Small Design/Build Installation!
A person is walking along a path next to a lake surrounded by trees.
By Andrea Hurd June 30, 2023
Is the drought over? Do we still need to conserve water in our homes? Can we go back to watering our gardens? Folks who live in Northern California, where we have been experiencing extreme drought conditions for the past several years, want to know.
By Andrea Hurd January 10, 2023
How we prep for planted areas at Mariposa
By Andrea Hurd January 2, 2023
As the drought lingers in California, and concerns about how to save water are at the forefront of our minds, many of us are thinking about how we can best conserve water in the garden.
More Posts