Wednesday, November 20, 2024

Further Comments on PW Water

On the Prince William Water website, you can find an information page on data centers. All their statements while true are incomplete and somewhat misleading in some instances.  This is part of a series discussing  more fully some of the issues they address. In the blog post below the bold face print is what Prince William Water posted the rest is my discussion.

Do data centers reduce available ground water for residents on private wells?

The drinking water provided by Prince William Water to serve new development in the western service area comes from public sources in the Potomac River and Lake Manassas, not from groundwater wells. Hence, public water supply does not affect ground water supply for private wells. 

True, the public water supply is drawn from the Potomac River for the western service area and the Occoquan Reservoir and Lake Manassas for the eastern service area. However, groundwater can be impacted by data centers (and development in general) in two ways. Directly and indirectly.

Directly. The water for data centers (cooling and landscape and miscellaneous indoor and outdoor use) comes from either public water supply (either potable water or reused water) or even potentially groundwater. There are no restrictions or permitting necessary for a data center to use a well for water supply in Prince William County. Watering lawns and landscaping at these large facilitiesthroughout the warm months uses a lot of water at these massive facilities also uses lots of water.

Data Centers are cooled using either air conditioning (electricity) or evaporative cooling (water). Evaporative cooling is more efficient and effective. Data centers that are water cooled use large amounts of water for cooling systems (even in closed loop systems), which ensure that the heat produced by these massive facilities is controlled. 

There are no restrictions or permitting necessary for groundwater use in Prince William County. The Virginia Water Withdrawal Reporting Regulation only requires the annual reporting of direct surface water and groundwater withdrawals each year of any entity withdrawing more than 300,000 gallons per month.

Reports made to DEQ for Prince William County indicate that 40,000,000-70,000,000 gallons of groundwater a year was being used for a pump and treatment system and 30,000,000-35,000,000 gallons of groundwater a year was being used by an industrial user (who I believe to be Amazon based on a conversation with DEQ). There are an unusual number of large capacity wells (100-750 gallons per minute) in the Manassas area that do not report to DEQ.  They could be pumping less than the reportable amount of water, or their owners simply unaware of their actual flow rate or the need to report use. Another way around the reporting requirements is to have several wells, none of which exceed the limit.

Ground water flow and storage is often viewed as static reservoirs that serve as the savings account for surface water flow. Through the hyporheic zone groundwater feeds streams between rain storms, but groundwater is dynamic and continually changing in response to human and climate stress [Alley et al., 2002Gleeson et al., 2010]. Changes in precipitation patterns, the amount of precipitation, the , and the changes in land use impacts available groundwater and surface water.

Land use changes that increase impervious cover, add more suburban lawns, roadways, buildings, pavement and eliminate woodlands does two things. It reduces the open area for rain and snow to seep into the ground and percolate into the water table and groundwater and the impervious surfaces cause stormwater velocity to increase preventing water from having enough time to percolate into the earth, increasing storm flooding and preventing recharge of groundwater from occurring. Land use changes also potentially increase the use of groundwater by adding more homes and businesses that utilize groundwater.

Very slowly, changes in land use change the ecology of the watershed and can reduce the water supply over time. As groundwater continues to be used levels fall, perennial steams that feed the rivers become intermittent during dry periods like this past summer and the summer of 2023. This is what appears to be happening in the Bull Run Mountain Conservancy area where for the second summer in a row   perennial streams stopped flowing in the summer.

Changing land use and the changing climate that are bringing  new patterns of rain and drought and are impacting the Occoquan Reservoir.  As Prince William Water points out: “Once used by data centers in western Prince William County, the wastewater is treated at the Upper Occoquan Service Authority Water Reclamation Plant and released as reclaimed water to the Occoquan Reservoir. In this water cycle, water used from the Potomac is reclaimed and released into the Occoquan Reservoir, adding volume.” Higher wastewater effluent while the changing climate and land use reduce river flow can introduce higher relative concentrations of minerals and salts, pharmaceutical, personal care and cleaning chemicals into the drinking water supply, potentially requiring additional treatment lines at great expense for all customers of the Griffith plant.

As Prince William Water points out: “Additional purchased (water) capacity must be timed in coordination with required infrastructure improvements for both Prince William Water and Fairfax Water, since purchasing additional capacity and delivering more drinking water may require infrastructure improvements.” Infrastructure improvements like additional treatment lines, additional reservoirs to assure continued availability of water are very expensive. In the billions of dollar range. This is reflected in the price of water. 

We need more information before we damage or destroy our fragile Bull Run and Occoquan Watersheds. We are paving over the watershed with roads, data centers, parking lots houses and electrical infrastructure reducing the groundwater recharge, reducing our stream flow and increasing the water demand. Although hidden in the subsurface, groundwater is the most important freshwater component in the hydrological cycle. Groundwater exists below all land with varying distance to the surface, but only in 20-30% of the land area is groundwater close to the land surface to feed surface streams and provide ecological services.

Groundwater releases water to streams sustaining the base flow of streams and rivers (Hare et al., 2021). Groundwater is the primary source of springs and many wetlands  (Bertrand et al., 2011; Havril et al., 2018; Gleeson et al., 2020a). Finally, the groundwater saturated subsurface, the hyporheic, makes up the largest continental biome contributing to the health and purity of our water resource. The small changes that the Bull Run Conservancy has reported in the springs, seeps and streams is telling us that our watershed is changing, and not in a good way.

It appears that even with just the current level of development, the depth to groundwater is increasing enough to disconnect some streams from the groundwater during summer months. These are the first small signs that the watershed is beginning to die- streams become intermittent and eventually become ephemeral- flowing only during rainstorms. These streams flow into the Bull Run and the Occoquan River that provide the portion of our eastern service area drinking water supply that is not from recycled wastewater. Of course as Prince William Water points out, increasing numbers of data centers will increase the amount of wastewater available, but that may not be all good. During rainless periods the fraction of treated wastewater could exceed the amount of natural water very soon. 

Prince William County is beginning to see changes in the Bull Run watershed.  The groundwater is becoming disconnected from Little Bull Run and Catlett’s Creek in the area of the headwaters of those streams. Once the hydrology and ecological biome is destroyed by development, it cannot be easily restored, if at all. Protecting the Occoquan Reservoir requires protecting all the water resources in a region because all water in the watershed is connected.

 


Kumari Yadav S (2023) Land Cover Change and Its Impact on Groundwater Resources: Findings and Recommendations. Groundwater - New Advances and Challenges. IntechOpen. Available at: http://dx.doi.org/10.5772/intechopen.110311.

Anke Uhl, Hans Jürgen Hahn, Anne Jäger, Teresa Luftensteiner, Tobias Siemensmeyer, Petra Döll, Markus Noack, Klaus Schwenk, Sven Berkhoff, Markus Weiler, Clemens Karwautz, Christian Griebler, Making waves: Pulling the plug—Climate change effects will turn gaining into losing streams with detrimental effects on groundwater quality,
Water Research, Volume 220, 2022, 118649, ISSN 0043-1354,
https://doi.org/10.1016/j.watres.2022.118649

Julia Zill, Christian Siebert, Tino Rödiger, Axel Schmidt, Benjamin S. Gilfedder, Sven Frei, Michael Schubert, Markus Weitere, Ulf Mallast, A way to determine groundwater contributions to large river systems: The Elbe River during drought conditions, Journal of Hydrology: Regional Studies, Volume 50, 2023, 101595, ISSN 2214-5818,

https://doi.org/10.1016/j.ejrh.2023.101595. (https://www.sciencedirect.com/science/article/pii/S2214581823002823)

 

Sunday, November 17, 2024

PW Water Comments Incomplete and Misleading

On the Prince William Water website, you can find an information page on data centers. The information while true is incomplete and somewhat misleading. Whether this is intentional, I do not know. I think it was intended to be comforting. Over the next couple blog posts I will more fully discuss the issues. In the blog post below the bold face print is what Prince William Water posted the rest is my discussion.

Do data centers use water for cooling?

Data center developers and operators use different cooling technology – water cooled or air cooled – based on several proprietary factors. The decision about which cooling technology is used is owner-determined and project-specific. 

Data centers generate heat. Servers and their related equipment generate a considerable amount of because every watt of power used by a server is dissipated into the air as heat. Feel the bottom of your own computer (this is why it is hard to keep the cat off the computer). The amount of heat output per server varies, depending on the type of chip and configuration. If the equipment gets too hot it will be destroyed. Data Centers are cooled using either air conditioning (electricity) or evaporative cooling (water). Evaporative cooling is more efficient and effective. In hot regions and with AI chips water cooling is preferred both for cost and heat removal ability.

In a water-cooled system, water-cooled chillers and cooling towers located on top of the data center roofs produce chilled water, which is delivered to computer room air conditioners for cooling the entire building. Some of this water can be recycled through the system more than once, recirculating the same water through their cooling systems multiple times while replenishing what evaporates.

According to Google, this practice saves up to 50% of water when compared with “once-through” cooling systems. However, eventually this reused water needs to be replaced with new water, due to mineral scale formation which could damage the cooling equipment or increase the conductivity of the water which could create static and damage the IT equipment.

The need for new water results from the build-up of calcium, magnesium, iron, silica, and salt which become concentrated by evaporative cooling cycles. The amount of water data centers consume also fluctuates based on seasonal weather conditions. Facilities typically use less water during the winter months and more during the summer months. We’ve seen this effect in water use data from Loudoun County.

Loudoun Water presentation to ICPRB showing seasonality of water use

Data centers are primarily located in the western areas of Prince William County. Western Prince William County drinking water is supplied by Fairfax Water’s Corbalis Water Treatment Plant, which draws from the Potomac River. Once used by data centers in western Prince William County, the wastewater is treated at the Upper Occoquan Service Authority Water Reclamation Plant and released as reclaimed water to the Occoquan Reservoir. In this water cycle, water used from the Potomac is reclaimed and released into the Occoquan Reservoir, adding volume.

The discharged cooling water that is too salty to continue reusing in the data centers is sent to UOSA wastewater treatment plant. This plant is not equipped to remove salt and minerals and so ultimately those excess minerals are mixed with all the other treated wastewater and released into the Occoquan River and flows right to the Occoquan Reservoir. During summer months and periods when there is no rain the treated wastewater is a significant and growing proportion of the water in the Occoquan Reservoir. For two generations UOSA has been a significant portion of the drinking water supply from the Griffith Plant which supplies eastern Prince William County through both American Water and Prince William Water.

The other sources of water to the Occoquan Reservoir are the streams (and groundwater-more on that Thursday) of the Bull Run water shed that flows into Bull Run and the streams (and groundwater) in the Occoquan Watershed that ultimately flow into the Occoquan River.

How much water do data centers use?

Data center water consumption depends on factors such as facility size, cooling type (water intensive or air cooled) and outdoor temperature. Prince William County had 34 data centers in 2023. Seasonal weather affects data center water use; facility water use is lower in winter and higher in summer. In 2023, data centers in Prince William County consumed approximately 1.4% of Prince William Water's average daily water demands and 6% of its maximum daily water demands. 

The industry treats water use (and everything else) it as a trade secret. However, Prince William Water 2023 financial report gives the water use for Prince William Water, 11,387,000,000 gallons for that year. The 34 data centers that existed in 2023 used in the neighborhood of 159,400,000 gallons of water (from Prince William Water- in addition a single data center user reported 35,000,000 gallons to DEQ from a well in Manassas).  Prince William Water also reports that 6% or 2,700,000 of the 44,400,000 peak use summer day was to data centers. It has been estimated that data center square footage will more than triple off of the 2023 number in the next 15 years.  

from PW Water 2023 Financial report
It should also be noted that the peak use day probably happened during the summer drought of 2023. The rainfall totals for May, June, July and August of 2023 were all below average in our area.  The reference year I used was from the  fiscal year 2023 which ended on June 30, 2023. The existing data centers in Prince William County and those coming on line in the next decade will continue to be supplied by the Corbalis Plant drawing its water from the Potomac River.  The Washington, DC, metropolitan area (WMA) is home to almost five million people, the federal government and commercial operations that support all of the people and government.

The regional water suppliers share the Potomac River as the sole major regional water resource. The waters of the Potomac are not infinite. Thirty-five years ago the regional water companies and came together to form the Interstate Commission on the Potomac River Basin (ICPRB) and a cooperative agreement (Co-Op) for planning and sharing the water resources available regionally.

 One of the most important functions of the ICPRB is that every five years they conduct a study to evaluate whether available water resources will meet forecasted water demands. The water resources of the Potomac River are limited. The most recent study accounted for both climate change and growth and  found that if droughts become much more severe as predicted in the climate forecast, even with the addition of the reservoirs in various stages of planning and construction: Vulcan Quarry, Milston Quarry, Travilah Quarry and Luck Stone Quarry B (adding over 13 billion gallons of water storage) and using water restrictions and demand management the Potomac River may be unable to meet combined water supply needs and the environmental flow-by at Little Falls during periods of drought. Even more water storage would be needed to ensure that during dry periods there is water for everyone.

Water demand from the Potomac River averaged 453 million gallons per day (MGD) for the for the last period reported in the study (2014-2018). The ICPRB projects that average annual water demand will increase to 501 MGD (10%) by 2040 and to 528 MGD (16%) by 2050. It is not clear how many data centers were included in the projections (if any), but the good news is that the ICPRB has a history of not adequately accounting for the adoption of low flow toilets and water efficient appliances so there may be some wiggle room in the forecast.

Nonetheless, the demand for water will increase. A wide range of evidence indicates that the earth has been warming over the past century and patterns of precipitation are changing.  These trends are likely to continue.  Likely changes in temperatures and precipitation will affect the availability, use, and management of water resources. The climate projections indicate that the mid-Atlantic states, on average, are becoming and will continue to get “wetter.” Climate scientists also warn, however, that floods and droughts will become more severe.  Our water infrastructure will have to include more water storage to meet a larger demand during longer droughts.

The summer of 2024 was a warm and dry. Though Hurricane Helene brought rain to us at the end of September, it was followed by the longest dry period on record -nearly 40 days. We are experiencing drought. Prince William Water and all regional water companies are attempting demand management because the flow of the Potomac River Water’s social media post featured November 7th  read in part:

“Metropolitan Washington remains under a Drought Watch, following several months of low rainfall with dry conditions expected to continue throughout the fall and winter months. The Drought Watch was enacted in July by the Metropolitan Washington Council of Governments (COG). 

A "watch" is the second level of COG’s four-stage regional drought response plan, designed to monitor water levels and address drought conditions throughout the year. Despite the current conditions, regional officials emphasize that there is an adequate supply of water in the Potomac River and back-up reservoirs.

We encourage customers to practice wise water use for indoor activities—like washing clothes and dishes, showering, and brushing your teeth--and for outside uses like watering their lawns or washing their cars. Prince William Water has wise water use tips available below. If you are continuing to water your lawn, we recommend following the outdoor watering schedule below…” Prince William Water goes on to give an alternate day watering schedule and recommendations on how homeowners can reduce water usage.

Everything is fine, but please conserve water. Meanwhile, Prince William Water states that they can purchase additional water supply capacity from Fairfax Water.

from Prince William Water

Can Prince William Water support the water demands of proposed data centers and residential/commercial development included in the Prince William County Comprehensive Plan and recent land use policies?

Yes. Prince William Water can support development activity as envisioned in the Prince William County Comprehensive Plan, including the latest Comprehensive Plan update which included the Digital Gateway, with capacity currently owned by Prince William Water supplemented with the purchase of additional capacity when needed from Fairfax Water. 

 As specific land use applications are submitted with the related water requirements, Prince William Water will continuously monitor and assess the availability of existing water supply and, if necessary, the required timing to purchase additional capacity from Fairfax Water. Any additional capacity from Fairfax Water would be withdrawn from the Potomac River. 

Meanwhile the ICPRB and Fairfax Water are working to build enough water storge in the system to meet the expected demand. There is a limit to how much water can be captured by reservoirs- it is not infinite.  As more treatment and watr storage needs to be installed in the Fairfax Water system, the cost of the Between 2022 and 2023 the cost of the water purchased (and a little less was purchased in 2023 than 2022) increase by 20%.

Thursday, November 14, 2024

Disinfect Your Well After the Flood

I read in the New Your Times this week that as the flood water in North Carolina has receded the U.S. EPA and the North Carolina Department of Health have been offering free water testing for the homes with private wells which are a third of North Carolina residents. Every well owner should test their well after flooding. The New York Times reports that so far the state and federal testing are finding that 40% of the wells are contaminated. This is not surprising, but there are actions that can be taken to restore the wells. If the mechanical components of the well were damaged by flowing debris the homeowner might be eligible for FEMA assistance. You can apply for FEMA assistance online or by calling 800-621-3362. The first thing is to repair any damaged equipment.

Severe flooding can cause septic waste and even chemicals from cars, stores and factories can enter groundwater making it unsafe to drink for days or even months depending on the extent of contamination and flow rate of groundwater. Essentially, anything that seeped into the groundwater will have to clear itself through natural attenuation (filtering by the soil and the contamination moving with the flow of the groundwater). A well may not be a safe source of water after the flood, but in all likelihood it will recover. Often all you need to do is flush the well then disinfect it.

Be aware that wastewater from malfunctioning septic tanks or chemicals seeping into the ground can contaminate the groundwater for several weeks if there was significant flooding.  The first thing you need to do is respond to any immediate problems and then test the water periodically to verify the continued safety of drinking water. Repeated disinfection and filtration can keep the water safe to drink until the problem is solved. If the well does not return to normal, a permanent water treatment system might be necessary if the grouting to the well casing has been damaged. A well professional can help you determine if a well needs to be replaced or repaired with treatment equipment installed. Years ago several neighbor’s wells were impacted by a flooded and failed septic system. It took several months for the contamination to clear, but it ultimately did.

Unless your well was submerged near a trucking depot, gas station, animal feed lot or other industrial or commercial source of chemicals it is likely that torrential rains or flood waters have infiltrated your well and you have “dirty or brownish” water from surface infiltration. This is especially true if you do not have a sanitary cap on your well or have a well pit. Historically, it was common practice to construct a large diameter pit around a small diameter well. The pit was intended to provide convenient access to underground water line connections below the frost line. Unfortunately, wells pits tend to be unsanitary because they literally invite drainage into the well creating a contamination hazard to the water well system. 

It is most likely if your yard was flooded or your well submerged that you have some surface infiltration of water including flood water from your septic system. In that case, chlorine shocking your well should disinfect your well and last at least 7-14 days you may have to do it more than once until everything is back to operating normally and any contamination in the groundwater has passed. Sadly, if you have a private well you are pretty much on your own. FEMA assistance might pay for well repairs or equipment, but you are going to have to take charge of the situation, and flush and clean your own well. After a flood, you are going to have to dry out your septic system and get it functioning again. If the flood waters were high enough to top the septic tank, have it pumped and go light on water use until the leach field dries out.

If your water is brown, the first thing you should do is run your hoses (away from your septic system and down slope from your well) to clear the well. Run it for an hour or so and see if it runs clear. If not let it rest for 8-12 hours and run the hoses again. Several cycles should clear the well. What we are doing is pumping out any infiltration in the well area and letting the groundwater carry any contamination away from your well. In all likelihood the well will clear of obvious discoloration. Then it is time to disinfect your well. This is an emergency procedure that will kill any bacteria for 7 to 14 days. It needs to be repeated until the source of the contamination is removed.

After 10 days you need to test your well for bacteria (and chlorine) to make sure that it is still safe. Testing the well for bacteria would determine if the water were safe to drink. A bacteria test checks for the presence of total coliform bacteria and fecal coliform bacteria. These bacteria are not normally present in deeper groundwater sources. They are associated with warm-blooded animals, so they are normally found in surface water and in shallow groundwater (less than 20-40 feet deep). Most bacteria (with the exception of fecal and e-coli) are not harmful to humans, but are used as indicators of the safety of the water. The chlorine test tells you if the lack of bacteria is due to the continued presence of chlorine. You need for both bacteria and chlorine to test negative to have successfully “fixed” your well.

To disinfect a well you will need common unscented household bleach.  For a typical 6 inch diameter well you need 2 cups of regular laundry bleach for each 100 foot of well depth to achieve about 200 parts per million chlorine concentration. You will also need rubber gloves, old clothes and protective glasses to protect you from the inevitable splashes, and don't forget a bucket to mix  bleach with water to wash the well cap.

  • Put on the old clothes and safety glasses
  • Run your hoses from the house to the well
  • Fill bucket with half water and half chlorine. 
  • Turn off power to the well
  • Drain the hot water tank
  • Remove well cap
  • Clean well cap with chlorine and water solution and place in clean plastic bag
  • Clean well casing top and well cap base using brush dipped in chlorine water
  • Pull wires in the well aside if they are blocking the top of the well and clean them with a rag dipped in chlorine water mixture. Make sure there are no nicks or cuts in the wires. 
  • Put the funnel in the well top and pour in the chlorine and water mixture
  • Now pour in the rest of the chlorine SLOWLY to minimize splashing
  • Go back to the basement and turn the power to the well back on
  • Turn on the hose and put it in the well 
  • Sit down and wait for about 45 minutes or an hour
  • After 45 minutes test the well to make sure that the chlorine is well mixed
  • Use the hose to wash down the inside of the well casing
  • Turn off the hose
  • Carefully bolt the well cap back in place
  • Now go back into the house
  • Fill your hot water heater with water, but do not turn it on to heat the water
  • Draw water to every faucet in the house until it tests positive for chlorine then flush all your toilets. Turn off your ice maker. 
  • Then do not use the water for 12-24 hours 
  • Set up your hoses to run to a gravel area or non-sensitive drainage area. The chlorine will damage plants 

 

After 16 hours turn on the hoses leave them to run for the next 6-12 hours. The time is dependent on the depth of the well and the recharge rate. Deeper wells with a faster recharge rate take longer. If you cannot run your well dry and it recharges faster than the hoses use water you will need to keep diluting the chlorine. If you can run your well dry, you might have to let it recharge and run the water off again to clear the chlorine.

After about 8 hours of running the hoses begin testing the water coming out of the hose for chlorine. Keep running the hose and testing the chlorine until the chlorine tests below about 1 ppm.

  • Drain the hot water heater again, open the valve to refill it and turn it back on
  • Open each faucet in the house (one at a time) and let run it until the water tests free of chlorine. Be aware the hot water will sputter- big time- until all the air is out of the system. Flush all the toilets
  • Change the refrigerator filter cartridge and dump all your ice and turn your ice maker back on. 

It is important not to drink, cook, bath or wash with this water during the time period it contains high amounts of chlorine whose by products are a carcinogen. Run the water until there is no longer a chlorine odor. Turn the water off. The system should now be disinfected, and you can now use the water for 7 to 14 days when the effects of the disinfection wear off. Hopefully, a single disinfection will be enough. 

Unlike public water systems, private systems are entirely unregulated; consequently, the well testing, and treatment are the voluntary responsibility of the homeowner. The local extension office (here in Virginia) or the local Department of Health can provide information and resource links for private well owners.   I am happy to answer emails or questions to the blog. Remember after you chlorinate a well the water typically runs brown until all the iron, iron bacteria and other minerals in the groundwater that you just oxidized are flushed out. Do not panic, it will clear.

I regularly chlorinate my well to knock back the iron bacteria and generally clean it out and refresh the water. For years I did this when my husband was out of town to avoid inconveniencing him for what I considered spring cleaning. During the pandemic when he was home during the chlorination, he was totally convinced that the continued sporadic reappearance of brown in the water was an indication that I had ruined the well. I had to tell him multiple times wait- it will clear. Finally, I just let the hose run for another 24 hours straight, and the brown was completely gone, and the test strips did not detect any chlorine. Usually, to be less water wasteful, I just get close enough and let time take care of it. (During this period I use bottled water or filtered water to make coffee and cook and then change the filter on the refrigerator when it clears completely.)  After a flood there are probably not water concerns so flush the well with abandon.

Sunday, November 10, 2024

Red Flag Warning for Wildfires

The Washington DC Region is officially in the longest dry streak on record at 40 days. We passed the previous record of 34 days with no rain last week and I hope the forecast for some rain on Sunday is just the beginning of a wetter winter than the summer turned out to be. Welcome to a changing climate. This is what it looks like.

It had been a warm and dry summer. Though Hurricane Helene brought rain to us at the end of September we are experiencing drought. Not much rain has fallen since that storm and warmer temperatures which the region has seen since June means higher evaporation rates and drier soils. Drought doesn’t just come from a lack of precipitation like rain or snow. Drought can also occur from higher-than-normal temperatures that can quickly dry out the ground.

Even if the total amount of rain stays the same or increases a bit, you can still get drought. That is especially true with more episodic rain. When we get a small number of big storms, all the water comes at once. The ground cannot soak it up, groundwater cannot be recharged, the existing reservoirs cannot store the water all at once. We get flooding that just flows to the rivers and the bay.

A wide range of evidence indicates that the earth has been warming over the past century and patterns of precipitation are changing.  These trends are likely to continue.  Likely changes in temperatures and precipitation will affect the availability, use, and management of water resources, but these changes will also impact wildfire risk.

A tweet from the National Weather Service

The extremely dry conditions across our region have led to an above average number of wildfires according to Maryland Officials. Conditions are not expected to change in the near future. The dry conditions have spurred the states of Maryland and West Virginia as well as the regions of Virginia in the Shenandoah Valley to declare a burn ban to prevent fires.

Burning yard trimmings or leaves is a common practice, but a dangerous one when the weather is dry and windy. This morning the wind was blowing something wicked and I smelled fire when I got the newspapers from the driveway. I do not know if someone was burning leaves or if there was a wildfire building somewhere..

According to the Virginia Department of Forestry, debris burning is the number one cause of wildfires, closely followed by intentionally set or “arson” fires. Fires are more likely during late winter and early spring because winds are usually elevated, the relative humidity is lower, and the fuels on the forest floor are extremely dry, having “cured” all winter without the shade of tree leaves. Those are the exact conditions we are experiencing now. The leaves fell early. 

Winds can blow burning yard waste and embers from firepits and debris burns far off site and ignite dried out and dead vegetation that has become combustible. We have allowed invasive plant species to choke off and kill many still standing trees in small wooded areas all over the region now after a summer where there were weeks without rain these are pockets of fuel for wildfires.

Potential fuel for forest fires that has since been removed

According to the Virginia Department of Forestry, nine out of ten wildfires are caused by humans (yes that includes arson). That means nine out of ten wildfires can be prevented by people, too.The easiest and cheapest way to suppress a fire is before it starts. Fall and spring are ideal times to reduce excess vegetation around your home that could pose an elevated fire threat.

Effective November 1, 2024, all open-air burning is prohibited in Front Royal and Warren County and much of the Shenandoah Valley and all of Maryland. Maryland’s ban will remain in effect until the Forest Service lifts it. West Virginia governor Jim Justice issued his state’s burn ban on Monday, November 4, 2024.

NOAA has issued a Wildfire warning. The entire region is now at red flag warning for wildfires. “Elevated potential for the rapid spread of fire is expected through midday due to the combination of dry conditions and gusty winds. Relative humidity values drop to around 25 % along with sustained northerly around 10 to 15 mph and gusts to 20 to 25 mph. This will result in the rapid drying of fine fuels like grass, leaves, and small shrubs. Residents and visitors are urged to exercise caution if handling open flames or equipment that create sparks. “

Wednesday, November 6, 2024

Drought in South America

Months of diminished rains have amplified fires, parched crops, disrupted transportation networks, and interrupted hydroelectric power generation in parts of Brazil, Bolivia, Colombia, Ecuador, Peru, and Venezuela. Drought impacts have been far-reaching. News reports indicate that the drought has strained power supplies in Brazil, Columbia and Ecuador as hydroelectric power stations generate less electricity. “The map below shows shallow groundwater storage for the week of October 7, 2024, as measured by the Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) satellites. The colors depict the wetness percentile, or how the amount of shallow groundwater compares to long-term records (1948-2010). Blue areas have more water than usual, and orange and red areas have less.” NASA


At the end of September 2024 Bogotá Columbia reinstated water rationing as water levels in the Chingaza reservoir system, the Colombian capital’s main water source, continued to fall due to a prolonged drought. Citing record-low rainfall and the urgent need to conserve water the Mayor announced that every resident will have to spend 24 hours without running water every nine days. The City is also banning the use of tap water to wash cars and water lawns.

The city began rationing water in the spring, but loosened restrictions during the rainy season (May to August) in hopes of the reservoir system reaching 70% capacity. However, the weather remained dry and by the end of October the reservoirs system had only reached around 50% capacity. The Chingaza water system has had it’s driest year-EVER.

Compounding the problem is that Columbia usually gets two thirds of its electricity from hydroelectric power. To conserve water, the energy regulator called on the fossil fuel-powered electrical generation plants to boost output.  

In October, 40% of power generated came from coal (one third) and natural gas (two thirds). Unlike neighboring Ecuador which has had daily blackouts to conserve water, the thermal plants that burn fossil fuels have been able to keep the lights on in Bogotá. Though, Columbia’s President Gustavo Petro aspires to reduce Columbia’s reliance on fossil fuels and has refused to allow new drilling for natural gas.

Colombia’s natural gas production has declined by 8.1% since 2023. Natural gas in Colombia is used for national transport system compression stations, residential heating and cooking, refineries, and electricity generation. Colombia relies on five natural gas fields which provide 80% of demand but have been declining since 2019.  Gas reserves have declined 58%.

Climate change vulnerability expands beyond water to electricity and to more developed countries.

Sunday, November 3, 2024

Record for Days without Rain

Northern Virginia is usually a fairly wet location. It rains about 44 inches a year on average. However, that is on average. The DC metro region has not had rain in 32 days. According to the ICPRB the region’s longest dry streak was in 2007 and ran 34 days.  At this time, no appreciable rainfall is expected in the next week so it looks like we’re going to break the record.

A wide range of evidence indicates that the earth has been warming over the past century, causing glaciers and sea ice to melt in many parts of the world, sea levels to rise, and patterns of precipitation to change. Most scientists agree that these trends are likely to continue and to accelerate due to increasing levels of carbon dioxide and other “greenhouse” gases in the atmosphere. Likely changes in temperatures and precipitation will affect the availability, use, and management of water resources.”

“According to projections from climate models, temperatures in the Potomac basin will rise whereas precipitation could rise or fall. Both temperature and precipitation have an impact on stream flows, and the range of available climate projections lead to a wide range of potential changes in water availability in the basin.”

"The primary climate models have predicted it is likely that storms will be more intense and droughts will be longer and more severe going forward. “Results project changes in long-term average summer basin-wide stream flows ranging from -35 percent to +42 percent, with a median of +2 percent, over the period between 1995 and 2040.” The region has been preparing for this variability by building billions of gallons of water storage still years away from being completed.   COOPClimateChangeFactsheet_Apr22-2013.pdf

On a positive note, the upstream drinking water reservoirs that we have in service are nearly full. These reservoirs would be used to supplement downstream flow in the case of a severe drought. The region has been planning for water supply shortages for years. The extended dry conditions have increased the area of Moderate Drought Conditions (D1) in the Potomac River watershed by almost 30% since last week alone. ICPRB staff is monitoring the river’s flow and keeping in contact with the region’s stakeholders. Due to low flow conditions and no rain in the forecast in the next 10 days it is expected that ICPRB will begin Drought Monitoring any day now. 

 The impacts from Tropical Storm Helene at the end of September hit the region with a excess precipitation a month ago. Since then, above-average temperatures and little precipitation have led to decreases in soil moisture for much of the Commonwealth as well as slight decreases in streamflow. Gages throughout much of Virginia monitoring network (which excludes the Potomac Watershed) indicate normal levels. Groundwater levels in most of the Commonwealth remain low and continue to exhibit seasonal and drought related declines, with Northern Virginia and Shenandoah regions reading less than the 5th percentile in groundwater. The 8-14 day weather forecast predicts normal to above normal temperatures and chances of slightly below average precipitation.

The most recent weekly U.S. Drought Monitor (USDM) web page map for Virginia (released October 31, 2024) showed abnormally dry (D0) conditions mapped across approximately 90.00 % of the Commonwealth and moderate drought (D1) conditions mapped across approximately 13.45 % of the Commonwealth. This is a significant increase from the previous week as the effects of the Tropical storms of September fade.



Wednesday, October 30, 2024

Farming Fish Not Environmentally Sound

 

Spencer Roberts, Jennifer Jacquet, Patricia Majluf, Matthew N. Hayek; Feeding Global Aquaculture; 2024/10/18; DOI: 10.1126/sciadv.adn9698; Journal: Science Advances Volume: 10; Issue: 42; Feeding global aquaculture

The below article is excerpted from the article cited above and the Press Release from the University of Miami and some thoughts from "Salmon Wars" by Douglas Frantz and Catherine Collins.

 

A study published this month in the journal Science Advances suggests that fish farming, or aquaculture, relies on much larger quantities of wild-caught ocean fish than previously calculated. These miscalculations have helped to portray fish farming as uniquely efficient or sustainable. Instead, the above cited study portrays fish farming like other forms of animal farming, albeit with a uniquely high reliance on wild fish extraction.

This wild fish extraction to feed the farmed fish also diverts millions of tons of food-grade fish (e.g., anchovies and sardines) and nutrients from countries with high rates of hunger to farmed aquatic animals (e.g., salmon and shrimp) intended for luxury markets of the world. Millions of people in Africa rely on fish for protein.

For too long, the fish-farming industry has wrapped itself in a cloak of virtue, asserting that it is feeding the world and putting healthy food on the table. The use of fish trimmings (heads, tails and guts) in feed is seen by many as a sustainable option and evidence of a circular economy in fish farming.  That is an illusion. The use of by-products and trimmings has not phased out the capture and use of whole wild fish in feeds for aquaculture. The offshore aquaculture industry is growing so rapidly that the wild-caught fish is not being replaced in their feed. Instead, other feed sources are just supplementing wild fish use.

Small fish such as anchovies and sardines are among the main species targeted for aquaculture fishmeal. The issue is that wild animals depend on these fish for food as well as the local communities. The 3,400-mile-long Atlantic coast of West Africa and the Pacific coast of Peru have been overfished to the point of threatening the viability of the native communities who depended on fishing and fish for survival. Penguins in Cape Town are declining largely due to the intense fishing pressure on sardines and anchovies and other species are also under stress.

The research cited above provides a reassessment of the "fish-in:fish-out" (FI:FO) ratio for global fed aquaculture to evaluate the efficiency and sustainability of aquaculture. By analyzing multiple industry-reported datasets, the researchers provided a range of estimates and highlighted uncertainties in current reporting practices. They found that the aquaculture industry relies more heavily on wild fish extraction than previous research had suggested.

The findings indicate that the ratio of wild fish inputs to farmed fish outputs is 27% to 307% higher than previous estimates, ranging from 0.36 to 1.15 compared to an earlier estimate of only 0.28. When accounting for wild fish mortality during capture and excluding unfed aquaculture systems, the ratio rises even further to 0.57 to 1.78. (The lower number reflects the use of terrestrial crops in some aquaculture species.) For carnivorous farmed species like salmon, trout, and eel, wild fish inputs likely exceeded twice the farmed fish biomass produced.

"Our study reveals that the aquaculture industry relies more heavily on wild fish extraction than previous research has suggested,” said Spencer Roberts, a doctoral student at the Rosenstiel School in the Department of Environmental Science and Policy, and lead author of the study. “This demonstrates the scale at which aquaculture could be impacting marine ecosystems."

The research team's approach included accounting for previously overlooked sources of wild fish in aquaculture feed, such as trimmings and byproducts from wild-caught fish. They also incorporated collateral fishing mortality, including "slipping"—a practice where unwanted catch is released but a large portion of the animals often do not survive. By analyzing multiple industry-reported datasets, the team provided a range of estimates and highlighted uncertainties in current reporting practices.

The researchers stress that while their study provides a more comprehensive view of aquaculture's environmental impacts, further research is needed to fully understand the sector's effects on issues such as nutrient pollution, habitat destruction, and the spread of diseases to wild fish populations.

Matthew Hayek, an assistant professor in the Department of Environmental Studies at New York University and the  corresponding author of the study, stated "It's crucial that we have a more complete understanding of the industry's impact on both marine and terrestrial ecosystems and reduce these uncertainties.” He emphasizes that even with the wide uncertainty ranges reported, the impacts are still larger than previously reported, and “most offshore finfish aquaculture facilities produce carnivorous fish, and therefore are responsible for depleting far more fish from the ocean than what they can produce.”