Plants Grow Even When We're Not Trying

It's the season where things start growing again. This little guy (who isn't so little anymore) has been steadily growing the past few weeks in the back of our little dump truck. A spring reminder that it's time to check your sprinkler system to make sure your sprinkler controller is set to water enough for the warmer weather that's coming up and to make sure everything is in working order. Call for a tune-up today!

California Super ARk Storm?

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Homeowners are asking what they should be doing to prepare for “the big one” a hypothetical storm-scenario being evaluated by the U.S. Geological Survey that could dump up to ten feet of water on California over 40 days. A popular saying is, “It never rains in Southern California!” But sometimes it does rain, and when it does, the consequences can be devastating.
Flooding of streets and hillside slippage are usually beyond the control of the individual homeowner, but there are steps homeowners can take themselves to reduce damage from rain storms in general, and which become even more significant in the event of “the big one.”.

Our experience is in treating ground-water intrusion problems, primarily for residential properties. In our work, we think of two types of storms of particular concern in Southern California: (1) Hard rain of 1 to 3 days; or (2) Persistent rain, whether hard or not, that persists over weeks at a time with little or no separation between storms. The first type of storm can simply overwhelm clogged or poorly designed drainage around a home and actually flood the home from the water getting too deep. This is a serious threat, but at least it is often visible to the homeowner. The second type of storm may flood the home, but in addition, it saturates the soil, continuously pushing more and more water into the soil. This type of storm saturates the soil to a greater depth, and water begins to move laterally underneath the ground. This is the type of water movement that is usually not visible, and because is it moving laterally underground may take days, weeks, or in some cases months before its effects are seen. This type of water movement can flood underfloor spaces, intrude into basements, saturate soil under slab-floors and footings, and create as much or more damage as a hard but brief rain. Typical home damage from ground-water includes mold and mildew issues under or in the house, actual flooding of floors and underfloor space, settling and/or cracking of foundations and concrete slabs, and warping of hardwood floors. In hillside areas, there is an additional hazard of land-slides.

For either of these two types of storms, there are fundamental principles that can be followed to minimize the hazard and damage to the homeowner. These are spelled out in the International Building Code. The overall idea is that water should not be allowed to pool or accumulate anywhere near the house, especially wood portions of the structure, but extending to all portions of the structure.

Roof Water

In our experience roof-water is the number one culprit to be addressed. The roof water falls represents a fairly large area that is dumped next to the foundation of the house in a relatively narrow area. This concentration can easily saturate the soil and lead to intrusion. Usually the easiest way to address this issue is to install gutters and downspouts, and take the water from the downspouts well away from the house, either over a concrete walk or driveway, or via underground pipe to the street.

The Grade Next to the House.

The building code calls for the grade next to the house to be at least 6 inches below and wood framing, which is usually at the top of the concrete foundation. Even though the wood framing may be covered with stucco, water can penetrate the stucco and cause mold, mildew, and wood-rot that can be very difficult and expensive to remedy.

Next the grade should slope away from the house at the rate of 6 inches over the first ten feet, and then 1/4 of an inch thereafter until reaching a drain device or the storm-drain system. This is a difficult requirement for many homes because they either were never graded this way when they were built, or sidewalks create dams that hold the water back against the house. Many homes have only a five foot side-yard, which means that some sort of physical drain system needs to be provided to get water away from the house. Water collected with such a system needs to be conducted safely to a natural drainage course or a storm-drain system to prevent undermining of the homeowners property and the property of the neighborhood.

On many existing homes it may be impractical to totally conform to these basic rules, so compromises need to be made. Such compromises should be consistent with the basic objective – capture as much water as is practical and get it safely away from the house. In some cases this may require the elimination of narrow planting beds adjacent to the house, or the installation of intensive drainage systems in such planting areas.

Subterranean Water

Subsurface water that builds up in the soil and moves towards the house, especially from a yard or neighborhood that slopes towards the house, may require a subterranean, or “French”, drain. This is basically a trench, usually deeper than the underfloor space or ideally deeper than the foundation, where the bottom is sloped in one direction, perforated pipe is installed along the bottom of the trench, and the trench is backfilled with gravel, with the excavated dirt typically being hauled away. The pipe discharges to an approved drainage system, as in the surface drain systems described above. In some cases, where there is not a suitable gravity route for the water, the water will need to be pumped to where it can then be drained off. The idea of this type of drain system is that water moving underground through saturated soil hits the more permeable gravel and percolates down to the bottom of the trench. There it begins to fill the trench, gets in the perorations of the pipe, and is conducted away from the property. When we get the type of storms where we have persistent, extended rain, the French drain becomes particularly useful for many properties.

Advance Preparation

Once the rains start, there is often little that can be done to prevent water intrusion until the rains stop. Therefore, it is important that homeowners prepare in advance for possible storms. Once appropriate systems are installed, they need to be regularly maintained. Gutters need to be kept clear of leaves and other debris, catch-basins need to be kept clean, sump pumps need to be tested, and blocked pipes need to be cleared. Typically preparations begin in October and November to prepare for the first rain. Sometimes it is important to repeat the maintenance after the first big rain to clear the system of accumulations from the rains. For vulnerable properties, additional maintenance may be required as the rainy season progresses.

While a super storm is not likely to happen, the buzz about it is a good reminder that we do sometimes get heavy rains here in the Los Angeles area and it's a good idea not to wait until it's too late to protect your property.

WHERE HAS ALL THE WATER GONE?

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“It never rains in Southern California”! In seven days starting in mid-December 2010, the Los Angeles area received over seven inches of persistent rainfall, averaging over one inch per day. On a typical 7,500 square foot city lot, that is almost 4,400 cubic feet of water, or roughly 33,000 gallons. Where does that water go? Unless a property is well-drained, too much of that rain-water ends up under the house undermining foundations, seeping through slabs, and flooding crawl-spaces. This in turn contributes to settling of floors and foundations, buckling of wood floors, musty odors, mold and mildew.

When rain hits the ground, it either runs off or soaks in. Soil can only absorb water at a limited rate. In very sandy soil water moves straight down at a high rate. In anything other than very sandy soil, water moves laterally as well as vertically through the soil. Water in saturated soil next to the house is moving towards the dry soil under the house. When the water hits the footings of the house, it percolates down, under the footing, and then comes back up under the house to the same level as the water outside the house.

Uncontrolled roof-water is the most common source of water under the house. Gutters are usually the easiest way to capture and control roof-water. Gutters redirect roof-water into downspouts. But if the downspouts empty the water next to the house, the concentration of water is magnified at the place of discharge and can actually make the threat more severe. Rain-water from gutters needs to be taken away from the house to a safe discharge. This can be done with a paved surface that does not allow the water to flow back towards the house, or with an underground pipe that takes the water to the street or other safe discharge location.

Water that lands on the yard next to the house needs to flow away from the house. If the yard is flat or sloping towards the house, the water will pond and saturate the soil, ending up under the house. To avoid this, the ground should slope away from the house at a rate of ½ inch per foot or more and go into a drainage system or onto yard with slope of 1/4 inch to the foot beyond the first 10 feet. Any water collected in a drainage system needs to be taken to an approved storm-water system, most commonly the street.

Water that soaks into the ground in the yard and neighborhood above the house can work its way downhill towards the house, eventually working its way under the house. When we have prolonged, continuous rains, such as the seven days in December of 2010, soils become saturated and lateral underground movement increases. This is when some water intrusion problems become more visible. The longer the period of continuous or frequent cycles of rain persists, the more likely subterranean water problems are likely to become apparent. These types of problems can sometimes be alleviated by improving the uphill surface drainage on the property, but often a French, or subterranean, drain system with perforated pipe and gravel is the most effective treatment.

Though it does not rain frequently in Southern California, when it does, the rains can create severe problems, especially where provisions for drainage are minimal or poor. In those cases, the answer to the question, “Where does all the water go?” is often, “In or under the house!”

Regular Yard Drain Cleaning And Maintenance

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If you have a yard drainage system that you depend on to carry water away from your house and property when it rains, you should make sure to maintain it. If you don't, you might not find out until it's too late that it's not working the way it's supposed to. Regular maintenance of a yard drainage system, including cleaning of catch basins, swales and drain inlets and snaking or hydro-jetting of drain lines, is very important. Debris, roots and dirt can eventually build up and choke your drainage system. We often find systems that haven't been maintained for years have pipes packed solid with dirt:






We recommend an annual drainage maintenance call before the rainy season. Hammer Company provides this service, which typically includes checking and cleaning all catch basins and drain inlets, snaking or high pressure water jetting of underground drain pipes, and testing to see if water introduced into these drains runs out the discharge as it's supposed to (usually to a curb drain at the street,) and if it does so in a timely fashion. If minor cleaning and drain clearing doesn't get the water draining as it should, we can investigate and/or replace portions of the drain line.

Additionally, sump pits should be regularly cleaned, at least annually, and sump pumps tested to make sure they will activate when you need them to.

A yearly maintenance call can save you a yard flooding incident or even water from getting into your house or garage. The water is much harder to deal with once that's already happened!

Storm Water Mitigation System Inspections

If you live in the City of Santa Monica and have an urban mitigation pit as part of your drainage system, you may be required to have an annual inspection for Best Management Practice (BMP) on an infiltration pit or depression basin. You might receive a letter from the City of Santa Monica that starts out like this:

"Your property has participated in the City's Urban Runoff Management Program through the installation of a Best Management Practice (BMP) device, such as an Infiltration Pit or Depression Basin, when construction work was performed in the recent past (since 1999.) The City's Urban Runoff Pollution Ordinance, SMMC 7.10, requires that most major development or construction projects install a physical structure within the property, in the landscape or under the garage (some commercial and multi-family buildings) or driveway, to capture precipitation from roofs and other hardscapes for infiltration or treatment and release to the street. This program seeks to keep small background levels of pollution found in urban runoff off City streets, where it flows untreated into the Santa Monica Bay, and can cause beach postings and closures. This program also seeks to harvest a local water resource and infiltrate it into the ground for groundwater recharge and potential future extraction as a local water supply, reducing dependence on expensive imported water or to harvest into a cistern for reuse."

What does this mean for you, the property owner? You may be required to have an annual visual inspection of your urban runoff mitigation or infiltration system, and turn in paperwork stating that you have done so. We can perform this visual inspection for you.


Our minimum Stormwater Mitigation System Inspection typically consists of:

1. Visual inspection of first-story gutters and any gutters visible from stair-case accessible upper story rooms or stair-case accessible flat roof. This inspection does not include putting our men on a slopping roof, or on a ladder extending beyond one story. If you want gutters inspected that exceed these limitations, we recommend contacting a gutter-cleaning company with appropriate workers compensation coverage for that work.

2. Where practical and accessible as provided in #1 above, hose-water test first-story downspouts to see if water flows through the spouts.

3. Visual inspection of deck and yard drain-inlets so see if they are clear of debris and silt.




4. Hose-water test of main drain from an accessible clean-out or drain inlet to see if water backs up. Basic inspection is based on one line only. If additional lines are needed and authorized, there would be additional cost. Note: A hose produces only a fraction of the flow of a rain-storm and does not detect less than full obstruction. For a more complete evaluation of drain condition the line would need to be snaked and/or videoed, neither of which is provided for in this basic inspection.




5. Visual inspection and quick clearing of pre-pit screen box (up to 12 X 12 by 18 inches deep. Larger or multiple filtration boxes will require additional time and cost.

6. Hose test of drain pipe from pre-pit screen box to pit. This is to verify that water does not back up into the pre-pit screen box.

7. Open inspection-hole cover at the pit and check for standing water. If the inspection hole access is buried, additional costs will be necessary to locate and access the inspection hole.

8. If overflow pipe inlet is accessible, hose-water test overflow pipe to see that it is clear to the street. Other wise run a tape or snake from the street outlet to see if the pipe is open from the street to the pit. Note: A hose produces only a fraction of the flow of a rain-storm and does not detect less than full obstruction. For a more complete evaluation of drain condition the line would need to be snaked and/or videoed, neither of which is provided for in this basic inspection.

Many single family residences, and some larger properties that are regularly inspected will fall within the minimum fee. The minimum fee covers 2 men for up to one hour. If problems are observed, we will report such problems together with recommendations, and where appropriate, estimate costs for treatment. If in-line filters are used on the site, the minimum charge does not include cleaning or replacing the filters. Depending on site conditions, we usually recommend eliminating multiple in-line filters and small pre-pit filter boxes and replacing them with one, large, serviceable filter and inlet box at the pit itself. Our minimum inspection does not include the cleaning of gutters or drains.

Some infiltration pits have been built with overflow drain pipes at the pit higher than inlet pipes. We do not recommend or approve such designs. Usually, we cannot determine whether or not the overflow pipe is lower than the inlet pipe without conducting a separate video inspection, which we do not include in our basic inspection, and is not typically required by the city.

Please take note that infiltration systems retain water on the site that normally would be conducted off the site. This can introduce unintended consequences of unpredicted proportions, especially where there are below-grade structural components such as basements and footings. Also, this type of inspection typically cannot tell us anything about the condition and capacity of the pit itself, or how effectively it is allowing infiltration into the soil. Also, because of the typical pit design, we cannot tell whether the pit will allow overflow water loads to actually reach the overflow pipe without backing up into the main system. In order to confirm this we would need to run a very large amount of water into the pit and observe its performance, which is not included in this minimal inspection. In inspecting the stormwater mitigation system we only report readily observable conditions and problems. We do not thereby approve or certify the overall suitability of the system for the site.

To order an inspection, please call and schedule it with our dispatcher. Please provide us with any information you may have regarding the location of the pit (or pits), the location of the inspection hole (not all pits have inspection holes), and access to a copy of any available plans or drawings used for construction of the pit. If you wish to have your drain lines snaked, hydro-jetted, or repaired during the process of the inspection, or filters and/or basins cleaned at the time of inspection, or sump-pits cleaned and pumps tested, please indicate so when you order the inspection and increase the budget to provide for additional work that will be charged on a time and material basis with the 2-man crew being billed at $170 per hour. The amount of time it takes to clean drain components can vary widely. Therefore we recommend a minimum of a $500 budget for combined visual inspection and minimal cleaning. If more extensive cleaning and or repair is needed, labor and incidental material for a full day on a job-site typically cost between $1,800 and $2,300. If you anticipate extensive problems with a large or old drain system, you may want to consider authorizing a budget of up to one day at a time for the most efficient use of the crew.

Sprinkler Efficiency Under Mandatory Restrictions In The Los Angeles Area

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High water bills have prompted homeowners to investigate the efficiency of the sprinkler system for their properties. Many homeowners trying to water within regulations or recommended watering levels are observing extensive plant stress, particularly in turf. When turf areas are under-watered they typically exhibit blotchy patterns of stress. Our experience is that such variability becomes manifest as water application is reduced due to multiple factors such as; uneven distribution of water over the area, varying soil conditions, shifting patterns of shade and sun, seasonal fluctuations in evaporation, and variations in weather. Other factors that produce similar symptoms include disease, animal urine, over- or uneven application of fertilizer.

Focusing only on water-related factors, it is necessary to water any given section of plant material to the highest need in that section in order to achieve relative uniformity of appearance. Except for very large areas such as football fields, golf courses, and large floral parks where spacing of sprinkler heads is not dictated by tight or curvilinear plant borders anything approaching optimum sprinkler application efficiency is not possible. Under the best conditions, the efficiency of application of water by sprinklers (or even drip) only approaches 70%. Typical urban and residential properties will be much lower, even with the best design and equipment. Statewide standards for irrigation efficiency have been developed based on ideal spacing of sprinkler heads in the absence of obstructions, imprecise borders, etc.. As a result, adoption of water conservation regulations has an overall fundamental bias against the typical homeowner from the beginning. This bias pushes the homeowner towards watering to the minimum for the least needy portion of a section of plant material, leaving the higher need areas stressed. With water regulations based on this type of standard, most homeowners will be penalized for higher than theoretically "necessary" watering levels to avoid stressing plant material.

However, there is an even more confining element to California state-mandated water regulations and standards -- that is choice of plant material. Even if a sprinkler system was at peak efficiency, much or most of plant material in residential gardens may exhibit severe stress under mandated water regulations or recommendations because most regulations are not based on existing plant materials or homeowner choices of desirable plant material, but on what someone else has decided homeowners should choose. Some people in power positions in the state and some communities have decided that the appropriate flora for Southern California is desert, and that anybody who chooses non-desert plant materials should be penalized with fines or higher water rates if they try to water accordingly. Tiered watering rates make sense when they relate to the increased costs of obtaining more water and are essentially tied to market forces. However, some communities are imposing much higher rates and penalties which are not tied to market forces but political ideology that impose an artificial uniformity of life-style. Under these definitions, a term such as "Excessive Use Charge" does not necessarily denote that a homeowner is being penalized for reckless use of water, but rather that the homeowner is being penalized for attempting to maintain plant material that does not conform with desert ideology.

This is important to understand because with typical home landscaping you can never be good enough to satisfy the standards of the regulatory agencies unless you severely stress or kill the plants. Even then it is important to realize that most water regulations are based on an annual average and do not allow for variations throughout the seasons. For instance, regulations in the City of Los Angeles only allow for watering levels at about 1/2 the summer level for the average landscape throughout the year, including the summer. Thus at this time of year, homeowners attempting to comply strictly with City of Los Angeles restrictions are experiencing severe dieback in their gardens.

With the above limitations in mind, the objective for sprinkler maintenance for existing plant material is to try to eliminate gross imbalance where practical. This will not eliminate plant stress, but will tend to even out the stress. Another measure that may provide practical benefits is to change the sprinkler controllers to ones that either automatically adjust watering times by season, or ones that have a weather sensor that adjusts watering times for daily changes in weather. Here's the rub, however. Under regulatory guidelines, watering times in the summer are about half the normal recommended level to maintain healthy plant material, especially for turf. Improving efficiency will improve, but not remedy that sort of problem. Also, smart controllers are typically designed to meet normal water needs of plants. Smart controllers will always call for watering beyond severe regulatory levels, and therefore have little impact throughout at least half of the year.

New Los Angeles Water Restrictions

Yesterday the LA City Council approved an updated version of the watering restrictions. Under the previous regulations watering was only allowed on Mondays and Thursdays. Under the new revisions you can water up to three times a week, and which days you may water are determined by whether your street number ends in an odd or even number.

Odd numbered addresses can water on Mondays, Wednesdays and Fridays while even numbers can water on Tuesdays, Thursdays and Sundays. If your address ends in a fraction, the number that precedes it determines your watering days.

Additionally, the amount you can water with traditional spray or bubbler heads has been reduced from 10 minutes per watering day per station to 8 minutes. Rotor heads and water-saving rotary style heads may be run for 15 minutes at a time, and twice per watering day per station, a definite increase from before, and an amount much more likely to keep your yard alive. It appears that those are the major changes. The new revisions will go into effect until 5 days after Mayor Villaraigosa signs them into law, probably by Labor Day.


The DWP's fact sheet can be found here.