March 2, the California Water Board has updated the proposed regulations for measurement of surface water diversions. You have to move fast to beat the comment deadline!
The notice is required to be given “…at least five working days prior to submission of a proposed emergency action to the Office of Administrative Law (OAL). Then, “After the submission of the proposed emergency to OAL, OAL shall allow interested persons five calendar days to submit comments on the proposed emergency regulations as set forth in Government Code section 11349.6. This document provides the required notice.” I haven’t called to check, but this could mean there are only 4 more days, until either March 6 (Sunday) or March 8 if “days” are M-F.
The definition of qualified persons is expanded, which will greatly help people with small diversions to comply at less cost, and sooner! Instead of just engineers, now contractors and “professionals” may install and certify measurement devices. The deadlines are stretched out somewhat – the biggest diversions (equivalent to 1.40 cubic feet per second 24-7-365, or 5.60 cfs for 90 days straight) and storage over 1,000 acre-feet per year haveto be done by January 1, 2017 – less than 10 months. The diversions equivalent to 0.14 – 1.40 cfs year-round, get six more months, to 7/1/2017. The smallest diversions, 0.014 cfs year-0.14 cfs year-round, get until January 2018. That makes sense – the Board gets the most bang-for-the-regulations with the large diversions.
In addition, the Board gives some estimated costs, which helps to plan for the expenditures. It can be expensive, but when done right, devices can last 10, 20, even 40 years in some cases:
That’s all for now. If someone already passed along comments that represent your water right interests, that’s great. If not, you have a few days to make your own comments.
This is an update and correction to the December 24 post, “Weirs – Planning, Building, & Measuring Flows“. In that post explaining the essentials of installing a weir box, I had said to excavate the pad 4” deep and fill with base rock. It should have said, excavate 8″. I’m sure you already figured out why: the weir bottom is about 4″ thick, so the weir floor would have been above the bottom of the ditch. By excavating 8″, and then filling with 4″ and compacting a level pad of 3/4″-minus road base, when the weir is placed the floor of the weir will be level with the bottom of the ditch. That way, the weir is not too high, where flow will undercut the base, and it is not too low, requiring extra boards to get a still pool upstream of the weir. The weir box in this photo is set – all it needs is for the water to be shut off, sides backfilled, and boards put in for easy measurement.
The important factor in figuring out where the weir gets placed along the ditch, is that the ditch needs to be straight upstream of the weir box. You can see in the photo above that the weir is located in a straight section of the ditch. When the box is placed in alignment with the straight ditch, the approaching water does not have to make a turn. Water going around a bend rolls toward the outside of the bend, and rolling or turbulent water might give a false reading of depth over the weir boards.
How long does the straight section of ditch have to be? The wider the weir, the longer the length of the ditch has to be straight. For a 1.0 foot-wide (1.0′) weir, which would pass a maximum of 1.0 cubic feet per second (cfs) if it worked as a suppressed weir, the minimum distance should be about 10′. For a wide weir box of 6.0′, the upstream distance should be 70′ or 80′.
How high do the boards have to be to provide an essentially still pool upstream of the weir? Remember the rule that the static head going over a weir, or the height of water that climbs up a 1/2″ engineering ruler held face-on to the flow, should be a maximum of 0.45′. A suppressed weir, with the flow width going from wall to wall as it goes over the weir, has to be 3 times that 0.45′, or 1.35′. 2 2″ x 8″ boards stacked up will get this height. If the weir is contracted, or cut into the board, then the board height only has to be twice the static head, or 0.90′. A 2″ x 12″ would take care of this. However, to be sure, never use less than 2 2″ x 8″ boards.
One more thing – the weir has to keep from collecting dirt or sand behind the boards. That means the boards may have to be lifted up every so often so the sediment can flush out. Weeds have to be kept down all around the weir so they don’t affect the flow of water. In the same way, sticks and grass have to be kept off the tops of the boards for the weir to work correctly.
The All Water Rights Blog has most or all of the information needed for a farmer or rancher to install a simple measuring device that is compliant with the recent regulations of the State Water Resources Control Board. I’ll have a couple of free ebooks by June, on how to install pre-cast weirs and orifices, as well as how to use them correctly, and report flows from small diversions to the Water Board. Actually, the ebooks will apply to larger diversions, too, except for the necessary pressure transducer needed to report hourly (and some day, 15-minute) flows to the Board.
There are certainly more complicated devices that require help, such as cast-concrete
Parshall and other flumes, mag-meters, acoustic Dopplers, or full-on gaging stations on rated sections of streams or ditches.
However, most diverters can (and many do) comply with the law with relatively simple devices. That’s it for now, I just wanted to get the word out on this.
Oh, and there will be an ebook some time around August, which has a working title of “Practical And Applied Water Rights In California – The Non-Attorney Book For Diverting Your Water”. That book will be more complete and will cost something, yet to be determined. Let me know what YOU want to see included in a book like this.
Weirs are the least expensive permanent measurement device you can install. Materials will cost the diverter in the range of $300 to $2,000; hiring the backhoe to set it in place probably costs more than the materials, unless the diverter already has a backhoe or crane.
The weir below was precast by Briggs Manufacturing in Willows. The weir is a cast concrete, 3-sided box with board slots for 2″ lumber. It’s pretty simple, and relatively easy to install. This particular weirneeded metal wing-walls to keep the dirt on the sides from washing out. Note that there are two board slots on each side, one for the boards to slide in, and the other to help make sure a nappe or air gap is created as water flows over the boards.
Step one is determining if there is enough fall in head from upstream to downstream. A weir needs 0.7 feet (0.7′), or 8.4 inches (8.4″) of fall to be sure it will work correctly. The 0.7′ figure is because the pool of water needs to be a maximum of 0.45′ above the top of the weir boards on the upstream side. Then, the water in the ditch downstream of the weir needs to be at least 0.25′ below the top of the boards so the water flows freely, separating from the boards and having an air gap on the downstream side. 0.45′ + 0.25′ = 0.70′.
The photo above shows a ruler in tenths of a foot, held vertically on top of the weir boards. This is called “sticking the weir”. When the ruler is turned face-on to the flow, the water will climb up to the same level as the flat pool upstream of the boards. It’s physics – standing water has an energy level equal to the height of the water surface. Moving water has both potential and kinetic energy, so the energy level or line is above the surface of the
water. Moving water stalls behind the face of the ruler, giving the height of the water if it were standing still. That is the water depth that has to be measured for weirs. The photo is showing a water level of 0.31′ – it wobbles up and down just a little – so we know this weir is flowing at about 0.6 cfs per foot of width.
If the ditch is very flat and shows no ripples when flowing, it’s probably too flat, and an orifice or a flume will be needed instead of a weir. Future posts will discuss those measurement devices, and others too.
Step 2 is figuring out how big a box is needed. Fortunately, there is an easy rule. 1.0′ feet of width is needed for every cubic foot per second (cfs) that will be diverted. For example, if the diversion will be a maximum of 3 cfs, then the diverter will need a 3′ wide weir. If in doubt, get the next larger size since the cost is not much more. The reason for this rule is that a weir can be accurate to plus or minus 5%, well within the accuracy needed for diversions in the field. If the pool upstream of the weir boards is more than 0.45′ over the top of the boards (or less than about 0.1′ over the top of the boards), the accuracy of the weir is worse than the standard.
Measurement devices need to be planned and operated correctly to assure the diverter (and ditch-tender, and neighbors, and the State Water Resources Control Board, andpossibly 10 other state and federal agencies, and possibly even the Superior Court in the very worst case) that the flow measurement is correct. It’s like a truck speedometer – they can get less accurate over time. It’s no problem if they read faster than the driver is actually driving, but if they read slower, the driver is in danger of unknowingly speeding and getting a ticket. Ouch.
The actual installation process is fairly simple to describe. Get 1 to 4 yards of 3/4″ minus road base rock delivered on site, trucked from the gravel plant. To save a lot of hassle, skip the forming up and pouring a concrete weir, and just callBriggs Manufacturing and order a weir to be delivered on site. Dig a shallow, level (flat), square hole in the bottom of the ditch, about 8″ deep, and 1′ longer and wider than the bottom of the weir. Shovel base rock into the hole about 2″ deep, and compact it. Rent a gas-powered thumper, or use the bucket of the backhoe. Pour another 2″ and compact it. Use a level and make sure the top of the base rock is level side to side, and along the ditch. Since it packed down during compacting, add the last 1″ and compact it, so the top of the road base is about 4″ below the bottom of the ditch upstream and downstream.
The installer needs to make sure to have a piece of 1″ steel bar that is about 1′ longer than the the width of the weir box. There is one hole through the top of each side of the weir – stick the rod through that and hook onto it with a chain to lift the weir. Set it in place, and make sure it is sitting level. The installer might have to gently press down on one side with the backhoe to get it completely level. Now the floor of the weir will be at the level of the bottom of the ditch. Remove the steel bar, and fill the weir box inside about 2′ deep with some dirt.
Next, install the wing-walls, if needed. These will keep the material on the outsides of the weir from washing out in a steeper ditch. Then backfill with the remaining road base on the sides, compacting it for each 6″ of depth. If thenative soil holds water well, it could be used instead of base rock to backfill, saving a little bit of money. Remember the dirt that was placed 2′ deep inside the weir? This will keep the weir weighted down so it does not move during backfilling. Also, it will keep the sides from being slightly bent in by the pressure of compacting the backfill. The reinforced concrete weir boxes are strong but the walls can be bent in with enough force.
That’s it! The weir box is installed and ready to go. New weir boards, usually 2″ x 6″ or 2″ x 8″, should be cut about 1″ shorter than the width inside the board slots. For example, a 3′-wide weir will have board slots about 2″ deep. The full width from inside of board slot, to inside of the opposite board slot, is 3′-4″. The boards should be cut about 3′-3″ long. That way, when they swell a little bit, they won’t get impossibly stuck.
Happy measuring! Good night to all, Merry Christmas, and blessings in the New Year.
What is “water rights engineering”? It is not litigating as an attorney, since I am not a lawyer. It could include design and construction of dams, diversion works, pipelines, pumps, and other water-related work.
Concerning water rights, land ownership may change after a water right is defined. Parcels are split so children can each have a part of the original ranch, or because the owner needs income, and a panoply of other reasons. What happens to the original water right?
Well, it depends. In many court adjudications, or decrees, the irrigation water right gets split up by how much of the original place of use is in each smaller parcel. Decrees may also have rights for other uses like domestic (household) use, stock water, storage in a pond or lake, instream fisheries, frost protection, industry, fire protection, and from years past, filling the water tanks in a train steam engine.
What kinds of water rights are there and where do they come from? More on that later.
Water laws are changing at lightning speed because California is in a historic drought. Groundwater law was passed requiring local agencies to be formed to manage groundwater. In 2012, I thought that would take 20 years to happen. The drought accelerated it to 2 years.
Surface water laws were passed in 2009, greatly increasing penalties for not reporting diversions, for misreporting, for overdiverting – in short, for evading, lying, and stealing. Suddenly tens of thousands of diverters who had been ignoring the State Water Resources Control Board started to worry. How do I report, am I in hot water if the Board sends me a letter, how do I figure out what my water right is?
” (i) On and after July 1, 2016, the measurement of a diversion of 10 acre-feet or more per year shall comply with regulations adopted by the board pursuant to Article 3 (commencing with Section 1840) of Chapter 12 of Part 2. “
That doesn’t sound too bad. But what does CWC 1840 say?
” 1840 (a) (1) Except as provided in subdivision (b), a person who, on or after January 1, 2016, diverts 10 acre-feet of water per year or more under a permit or license shall install and maintain a device or employ a method capable of measuring the rate of direct diversion, rate of collection to storage, and rate of withdrawal or release from storage. The measurements shall be made using the best available technologies and best professional practices, as defined in Section 5100, using a device or methods satisfactory to the board, as follows:
(A) A device shall be capable of continuous monitoring of the rate and quantity of water diverted and shall be properly maintained. The permittee or licensee shall provide the board with evidence that the device has been installed with the first report submitted after installation of the device. The permittee or licensee shall provide the board with evidence demonstrating that the device is functioning properly as part of the reports submitted at five-year intervals after the report documenting installation of the device, or upon request of the board.
(B) In developing regulations pursuant to Section 1841, the board shall consider devices and methods that provide accurate measurement of the total amount diverted and the rate of diversion. The board shall consider devices and methods that provide accurate measurements within an acceptable range of error, including the following:
(i) Electricity records dedicated to a pump and recent pump test.
(ii) Staff gage calibrated with an acceptable streamflow rating curve.
(iii) Staff gage calibrated for a flume or weir.
(iv) Staff gage calibrated with an acceptable storage capacity curve.
(v) Pressure transducer and acceptable storage capacity curve.
(2) The permittee or licensee shall maintain a record of all diversion monitoring that includes the date, time, and diversion rate at time intervals of one hour or less, and the total amount of water diverted. These records shall be included with reports submitted under the permit or license, as required under subdivision (c), or upon request of the board.
(b) (1) The board may modify the requirements of subdivision (a) upon finding either of the following:
(A) That strict compliance is infeasible, is unreasonably expensive, would unreasonably affect public trust uses, or would result in the waste or unreasonable use of water.
(B) That the need for monitoring and reporting is adequately addressed by other conditions of the permit or license.
(2) The board may increase the 10-acre-foot reporting threshold of subdivision (a) in a watershed or subwatershed, after considering the diversion reporting threshold in relation to quantity of water within the watershed or subwatershed. The board may increase the 10-acre-foot reporting threshold to 25 acre-feet or above if it finds that the benefits of the additional information within the watershed or subwatershed are substantially outweighed by the cost of installing measuring devices or employing methods for measurement for diversions at the 10-acre-foot threshold.
(c) At least annually, a person who diverts water under a registration, permit, or license shall report to the board the following information:
(1) The quantity of water diverted by month.
(2) The maximum rate of diversion by months in the preceding calendar year.
(3) The information required by subdivision (a), if applicable.
(4) The amount of water used, if any, for cannabis cultivation.
(d) Compliance with the applicable requirements of this section is a condition of every registration, permit, or license.
(Amended by Stats. 2016, Ch. 32, Sec. 98. Effective June 27, 2016.) “
Now THAT has a punch. There are exceptions in following paragraphs, but the Board now wants “continuous monitoring”, meaning one of the older, mechanical Stevens Recorders and the like, or newer, electronic pressure transducers. Now we are talking $500 and up just for recording data, in addition to a measurement weir, flume, or orifice.
And the diverter has to provide “evidence”. How is that done? Is a photo good enough? A video? A drawing? A statement by the local ditch tender, the Resource Conservation District, a technician, or an engineer?
Of course, the Board has higher priorities with larger diversions, and streams with anadromous (chinook and steelhead) fisheries. Still, it is an open question about when the Board will get to your or my diversion.
Complaints from neighbors with a grudge tend to elevate problems that the Board considers. But, water is nothing to argue over, is it? Or have grudges?