Watershed Investments NC

Detailed in a July 2017 news story, the occurrence of extreme low-flow conditions in NC piedmont streams is increasing.  The story is based on USGS research,  that looked at the 7-day, 10-year (7Q10, W7Q10) low-flow discharges.  The 7Q10 is the lowest average discharge over a period of one week with a recurrence interval of 10 years. The measure identifies rare and extreme events of low water flow in streams.

The USGS report summary findings for 7Q10 trends at 63 gages with 30 or more years of climate date include the following:

• The 7Q10 discharges did not change for 3 sites,
• 5 sites had increased discharges with a median of +13.2%;
• 55 sites had decreased discharges with a median of -22%;
• The median percentage change for all 63 stream gages was –18.4 percent.

Factors such as increased development, increased water withdrawals from agricultural, industrial, and municipal users, and erratic rainfall patterns contribute to the reduced flow critical for drinking water and dilution of pollutants.

Indeed, findings from UNC researcher Nathan Hall presented at this year’s WRRI conference pointed out that recent algal blooms in the middle Cape Fear River are directly tied to low-flow events.  Hall summarized the following:

1. Recent, extreme, summertime low‐flow events provide sufficient light and travel times for algal bloom development.
2. Stratification likely plays an important role in determining overall phytoplankton biomass and competitive dominance by positively buoyant cyanobacteria.
3. Recent increase in blooms likely related to flow rather than increasing nutrient concentrations because nutrients are, and have been, replete for a long time.

What’s this all mean? Most importantly, our water is a finite resource that needs to be protected to insure that both human and natural uses are sustainable.  Water wars can be found throughout the US and given the trends found in this USGS research, we need mindful policies to insure they don’t happen here.

Eastern NC saw major flood events in October 2016 and April 2017.  The most recent storm was centered a little west of the catastrophic rain from Hurricane Matthew.  Flooding from both of these events, however, were able to be mitigated somewhat by the presence of Falls and Jordan Lake reservoirs in the Triangle.

Both Falls and Jordan reservoirs are manmade with construction beginning in the 1970’s. In the Triangle area, these lakes receive much attention for their ole of providing drinking water to the growing region.

The largest portion of these lakes storage, however, is dedicated to flood control.  This function was in the news recently as the Army Corp had to release higher volumes of water from Falls Lake to maintain the lake’s ability to provide flood storage. While these releases do have minor flooding impacts on those near the dam, they are not as severe or extreme as flooding that would have occurred had the dams not been built.  Plus, by freeing up more flood storage, they help to mitigate the chance of extreme flooding downstream.

For the second time in about 6 months, Crabtree Creek was in full usage of its floodplains as the Raleigh area received around 7 inches of rain over two days.

Heading down to the greenway along the Creek the week after the rain, we came across this indicator of urban flooding – plastic bags littering suspended tree branches.  It’s one indicator of the being in an urban watershed and the need to try to reduce the amount of plastics we use.

There were other indicators of flooding: washed out sections of greenway pavement, knocked down fencing, and muddy trails.  Remarkably, however, the undeveloped floodplains were functioning in the way that they should and infiltrating the floodwaters that had inundated the area. It was interesting to see these areas doing what they are supposed to given the major flooding a few days earlier.

Partnerships with landowners are the cornerstone of a project. Our partnership with Nettie Gambill on the Neville Farms site has been a professional highlight and I’m happy she was willing to tell her story for us to share.

At this month’s Environmental Management Commission meeting, the NC Division of Water Resources provided an update on trends in animal production and its nitrogen and phosphorus waste byproducts as it relates to our state’s watersheds.

Water quality monitoring of the State’s Neuse and Tar-Pam watersheds has demonstrated nutrient pollution of these water bodies and resulted in their being listed as impaired. Meanwhile, the state’s efforts to curb pollution sources like waste water treatment plants and runoff from farms and development have not resulted in measurable improvement to the estuaries.  .

One belief was that increased animal waste is the source for nutrients preventing reductions in the overall nutrient loads flowing to the estuaries.  That belief is what led to the report to the commission.

What were the report’s findings? For the nutrient sensitive waters of the Neuse and Tar Pam, here are some results:

• Between 2006 and 2014, plant available nitrogen (PAN) (i.e., nitrate (NO3), and ammonium, (NH4)) was estimated to have declined from 13 million lbs to 10 million lbs.
• For the phosphorus (P205), levels dropped from 15 million to 11 million lbs.
• Total poultry numbers stayed around 19.5 million birds from 1992 to 2006 and dropped to 16 million birds in 2014.

The report illustrates the complicated nature of nutrient management.  While the amount of animals and animal waste may be declining, monitored nutrient pollution flowing to the estuary shows little change. Its findings show that regulators need to broaden their scope to find solutions to the problem of nutrient pollution.

For at least half a decade, legislative support for environmental protections at the state level has been shaky. This wavering support, at least partially, is based on the belief that these protections stifle job growth and development.  A study by UNC’s Todd BenDor highlighted in an article in the Ecosystem Marketplace, however, rejects this argument and demonstrates how the restoration industry has been an important part of North Carolina’s and the national economy.

According to Bendor, ecological restoration employed more people than coal mining, logging and the iron and steel industry.   As the article states:

Those jobs are part of a $25 billion “restoration economy” that directly employs 126,000 people and supports 95,000 other jobs – mostly in small businesses.

These jobs go to engineers, the construction industry, plant suppliers, biologists, and foresters.  These professionals, in turn, identify former wetlands and degraded streams-typically lower productive farmlands, develop restoration plans, implement those plans and monitor their results.  What’s more, North Carolina has one of the leading restoration industries based on market-oriented policies implemented during the 1990’s and 2000’s.

These market approaches, however, are founded on government policies that seem to be falling out of favor. Given that they are an important employer on both the state and national level and one that brings jobs and money to rural areas, the restoration economy is one that should be supported as a contributor to providing balanced growth.

BenDor T, Lester TW, Livengood A, Davis A, Yonavjak L (2015) Estimating the Size and Impact of the Ecological Restoration Economy. PLoS ONE 10(6): e0128339. doi:10.1371/journal.pone.0128339

On a recent frosty December morning, we planted the Neville Farms Mitigation Site with over 2700 native hardwood plants. The work went smoothly and the planting conditions were good. Planting in the winter allows the trees to start establishing their root system giving them a head start for the spring when they’ll help restore natural habitat in the floodplains feeding Jordan Lake.

For years, Jordan Lake has been plagued by excess flows of nitrogen and phosphorus that have led to excess algae and water quality conditions that do not support the uses it should.  Lake clean-up plans were approved by the state in 2009 but actions by the NC legislature have delayed their implementation and prevented broad, pollution reducing actions from being implemented.

The Neville Farms project was developed as part of the original clean-up strategy passed in 2009.  The trees planted at this site will restore natural functions to the floodplain, slowing flood flows and allowing polluting sediments and nutrients to be deposited in the floodplain where they’ll serve as nutrients for newly planted trees and shrubs.

It felt good to get to this stage of the project. Even if the Jordan strategy isn’t fully implemented, this restoration project will continue providing beneficial functions. It will take, however, implementation of many more pollution reducing projects like this, and commitment from the State to show measurable water quality improvement in Jordan Lake.

It’s been about a month since Hurricane Matthew unleashed devastating flooding on eastern North Carolina. According to news reports, that flooding inundated swine waste lagoons, farm fields, chicken houses, wastewater treatment plants, and even a coal ash pond, washing the resulting mix of pollution downstream to our sounds and estuaries.

Typically, freshwater flows from the Neuse and Tar rivers feed the estuaries but have a long residence time once they get there.  In part, that’s because these waterbodies are large and the State’s barrier islands impede the ability of  river water to quickly exit to the ocean.

With all the pollutants in the water, however, a lazy trip to the ocean is not ideal.  It results pollutants settling to river bottoms and banks.

Enter the big flush.  This is the result of the extreme flooding pushing downstream.  That pressure helps push water more quickly through the sounds and out into the ocean.  You still get settling of pollutants, just less of it.

The above effect can be seen in monitoring data from UNC. The graphic below shows a monitoring of several parameters in the Neuse River Estuary during similar timeframes in October of this year (2016) with that of last year (2015). At the top of the graph is salinity in October.  Salinity in the river typically rises in the summertime and pushes upstream as freshwater flows are reduced. Those levels then gradually decrease as fall moves into winter and river freshwater flows increase.

On the lower graph from late-October 2016, however, you see how the flooding from upstream has quickly lowered salinity pushing freshwater far down the estuary out to the ocean.

Is the pollution damaging to the ecosystem?  It must be. The effect of coal ash, pig and human waste, oils, and other pollutants lingering in the estuary will be something to study in the coming months. The flushing, however, helps mitigate the harmful effects of all these pollutants in the estuaries by flushing much of them out to the ocean.

Hurricane Matthew is no more but here in NC his affects are still being felt.  Many inches of rain fell on soils that were already saturated in many parts of the State.  The result was flooding conditions that persist from the Triangle to Eastern North Carolina.

Earlier this year, I touched on the role of floodplains in reducing impacts from flooding.  Well, those in the eastern part of the State will be pulling a heavy load as waters from the Creeks around Raleigh make their way to the coast.

In the Neuse, where record flooding has occurred at Smithfield, Kinston is the downstream end where floods pass before widening out into wider wetlands and, finally the estuary.  Floodplains in these areas will be helping to reduce erosion and deposit sediments and pollutants before they make it to the tidal estuaries.

Still, the pollution washing into the Neuse and Pamlico sounds will be terrible. Soil, waste lagoons, broken sewer and septic systems and other pollutants will end up washed into our rivers. Combined with the flooding, it will be catastrophic event for the state on many fronts.  This storm is a tough hit for our state illustrating the destructive power of nature.  It also demonstrates that we need to take proactive measures to protecting our natural assets like floodplains and wetlands that help to mitigate the impact of storms.

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Following up on prior post on what it takes to restore nutrient impaired waters, the Chesapeake Bay Program released an update on their improvement progress.  They report:

According to data from the CBP and the U.S. Geological Survey (USGS), nitrogen, phosphorus and sediment loads to the Bay were below the long-term average in 2015. Between 2014 and 2015, nitrogen loads fell 25 percent, phosphorus loads fell 44 percent and sediment loads fell 59 percent. Below-average loads are considered positive because reductions in nitrogen, phosphorus and sediment pollution can improve water quality.

The most recent assessment of water quality—which examines dissolved oxygen, water clarity and chlorophyll a (a measure of algae growth) in the Bay and its tidal waters—makes these improvements clear: between 2013 and 2015, an estimated 37 percent of the tidal Chesapeake met water quality standards. While this is far below the 100 percent attainment needed for clean water and a stable aquatic habitat, it marks an almost 10 percent improvement from the previous assessment period.

So, actions by the Bay states to reduce polluted agricultural and urban runoff and along with nutrient loads from wastewater plants is having a marked effect on improving water quality in the Bay. Implementing actions that solve problems – that’s a model that NC should follow to deal nutrient pollution instead of the delaying tactics which are doing nothing to help clean up our impaired waters.