All in the Numbers
How and why many states continue to move from narrative to numeric nutrient criteria
Excess nutrient pollution has rallied municipal, state, and EPA officials together, working to update the criteria to improve water quality throughout the country, though the very nature of the work is moving forward in small, gradual steps.
In 1998, the EPA recommended water-quality criteria for nutrients under the Clean Water Act. The recommendation was intended to guide states and territories as to how they could develop nutrient criteria that would be more region-specific to water bodies in their areas and that could be adapted into their individual water-quality standards.
When excess nutrients, primarily nitrogen and phosphorous, in a body of water cause algae to bloom, this algae can use up oxygen needed for other aquatic life during a process known as eutrophication. The side effects of eutrophication can be a foul smell, slimy water, and, in some instances, fish kills.
There are numerous potential sources of eutrophication.
“Potential sources of nutrients include wastewater treatment facilities; septic tank–leach field disposal systems; animal feeding operations; aquaculture; agriculture; permitted runoff from confined animal feeding operations; rangeland grazing; urban runoff and storm sewers; construction sites; hydromodification; drought-related impacts, which reduces the dilution; pet wastes; atmospheric deposition; wildlife and waterfowl; and natural sources such as the geology and soils,” explains Shelly Drinkard, nutrient and lakes team leader at the New Mexico Environment Department Surface Water Quality Bureau based in Santa Fe.
“Multiple sources require multiple solutions,” says Eric Livingston, bureau chief for watershed management at the Florida Department of Environmental Protection in Tallahassee. “We’re all part of the problem, and we all have to be part of the solution.”
Defensible Measurements
While the EPA has for many years recognized the importance of controlling nutrients such as nitrogen and phosphorus as part of water-quality protection, explains Mike Bira, nutrient regional coordinator for the EPA’s Region 6, “The complicated chemical, biological, and physical interactions which determine exactly how nutrients affect individual water bodies is the subject of much study.” He says federal, state, and local entities continue to work together to create numeric nutrient criteria as part of a state’s water-quality standards. The states set water-quality standards with the intention of having them approved by the EPA.
“Basically, the way acceptable levels are determined is through the establishment of designated uses for water bodies,” says Bira. “Once uses are established, criteria are developed to protect uses. Criteria are scientifically defensible measurements to determine whether or not uses are being met.
“Criteria may be either numeric, such as ‘a minimum dissolved oxygen concentration of 2.0 milligrams per liter,’ or narrative, such as a concentration of ‘X’ cannot be at a level which causes excessive algal growth. Currently, all five EPA Region 6 states—Arizona, Louisiana, Oklahoma, New Mexico, and Texas—as well as most of the states in the US, have set narrative criteria for nutrients. EPA sees the use of numeric criteria for nutrients as much more protective of water quality.”
The narrative standard was the criteria followed prior to the EPA’s recommendation that numeric standards be established.
“To me, its pretty obvious that a hard, scientifically defensible number is much more useful in determining water-quality impairment than a narrative description,” says Bira. “There is much ambiguity in typical narrative language like ‘significant’ or ‘excessive.’ For example, excessive plant growth to a swimmer is much less than to a bass fisherman.”
Numeric criteria would serve as an equalizer of sorts that could clarify for municipalities specifically what is expected of them.
“In the 2001 guidance document, we do recommend specific numeric values, and we recommend states develop their own, too,” says Brian Thompson, the Chicago-based nutrient water-quality standards coordinator for EPA Region 5.
The states in Region 5—Illinois, Indiana, Ohio, Michigan, Wisconsin, and Minnesota—are progressing as far as developing nutrient water-quality standards, putting forth a good effort, and following the 2001 EPA recommendations, Thompson says. They reference condition criteria that identify the “water quality that is considered to be minimal impact” and set the criteria at that level, says Thompson.
“A second option is to identify some kind of relationship between nutrients and adverse effect,” he says. “In many cases [there are] a combination of those two approaches.”
Most states are communicating with local or municipal stormwater programs, according to Bira, updating them on progress at the EPA regional level.
“In my experience with our states, this has been a very open process, and if anybody feels the need to know more, access to the state staff has been quite easy,” he explains. “Our Region 6 states all have the most current information on their Web sites.”
Gary Welker, Ph.D., a Kansas City, KS–based nutrient coordinator for EPA Region 7, says a regional technical advisory group has been established to develop nutrient benchmarks for streams, rivers, and lakes. Agencies in Kansas, Nebraska, Iowa, and Missouri are working with universities in those states to build this criteria.
“This tech advisory group is using existing data, modeling, literature values, and collecting data. Ultimately these levels are to be set by the states. Currently there are these advisory groups going on in our state as well,” he says. “In our four states they will be tailoring their own criteria.”
These figures will be based on climate, topography, and geology.
“Our whole approach began with the Clean Water Action Plan, the document from Al Gore,” says Welker. “One of the action items in the action plan was to develop criteria in ’98.”
Of the Region 7 states, only Nebraska has submitted criteria for review so far, says John DeLashmit, chief of water-quality management for EPA Region 7, adding that all of the states can be characterized as on schedule for developing the numeric criteria.
“Each one of the states is taking a similar approach—lakes and reservoirs first, then streams and rivers,” he says, noting that it is easier to determine criteria for non-flowing waters. “Kansas has put in place a nutrient reduction strategy. They are planning to reduce the concentration of the amount of nutrients in waters leaving the state of Kansas by 30%. When you read their plan, they lay out exactly how they are [going to accomplish this].”
Developing Criteria for Impaired Versus Unimpaired Waters
Alabama also has taken steps to create numeric criteria for various water bodies. “The Alabama Department of Environmental Management [ADEM], with some assistance provided by state-contracted consultant Tetra Tech, remains in the ongoing process of developing numeric nutrient criteria levels for water bodies within the state,” says Stan Shirley, a senior environmental specialist in the water division of the Alabama Department of Environmental Management based in Montgomery. “Numeric nutrient criteria have already been developed for various major unimpaired lakes and reservoirs using a ‘weight of evidence’ approach. This approach relies on historically and recently collected chlorophyll a levels to establish protective site-specific chlorophyll a levels for each major unimpaired lake or reservoir.” Chlorophyll a, a blue-green pigment, can be used as an indicator of how much algae is present in the water.
Three-dimensional water-quality models that can help the department determine the appropriate nutrient levels for Alabama’s major impaired reservoirs and lakes are under development and are expected to be completed in the near future. Total maximum daily loads (TMDLs), water body–specific figures developed for individual nutrients, are part of that process.
“The development of nutrient TMDLs for 303(d)-listed or impaired rivers and streams, as well as the establishing of nutrient criteria for rivers and streams as a whole, has used a reference site approach,” says Shirley. “ADEM is also in the developmental stage of determining numeric nutrient criteria levels for estuarine and coastal waters. ADEM is an active participant of the Gulf of Mexico Alliance cooperative, which is composed of the state environmental protection agencies of Alabama, Florida, Louisiana, Mississippi, and Texas, as well as the federal government and other concerned entities whose aim is to share science, knowledge, technologies, expertise, and financial resources to better protect the health and complex ecosystem in the Gulf of Mexico.”
New Mexico’s Surface Water Quality Bureau’s Monitoring and Assessment Section worked with the EPA and the US Geological Survey to develop numeric criteria for nutrient standards in wadable streams throughout the state in the form of a nutrient assessment protocol. The threshold values presented in the protocol continue to be tested before being adopted into the New Mexico Water Quality Standards, and the process of developing similar approaches to propose nutrient criteria for other bodies of water including wetlands, lakes, reservoirs, and rivers throughout the state has been outlined for the future.
Municipal stormwater programs are inspected throughout the state, according to Richard Powell, industrial team leader at the New Mexico Environment Department Surface Water Quality Bureau in Santa Fe, as are construction areas and industrial facilities.
New York, New Jersey, Puerto Rico, and the US Virgin Islands comprise EPA’s Region 2. New York uses numerical guidance values, such as the existing ambient water-quality guidance value of 20 micrograms per liter for phosphorus that has been established for Classes A, AA, A-S, AA-S, and B waters; water body-specific values, including the target total phosphorus (TP) concentration for Lake Erie that is divided up by basin, with the Western Basin equal to 15 micrograms per liter and the Central and Eastern basins equal 10 micrograms per liter; and narrative standards to address water-quality impacts from nutrient over-enrichment, according to the EPA Region 2’s Division of Environmental Planning and Protection (DEPP) staff. The state currently is working to add numeric values for nutrients present in lakes, reservoirs, rivers, and streams, staff members report.
Similarly, New Jersey uses both narrative and numeric criteria for total phosphorus as part of the state’s Surface Water Quality Standards. For example, total phosphorus in the state’s streams may not exceed 0.1 milligram per liter unless “it can be demonstrated that total P is not a limiting nutrient and will not otherwise render the waters unsuitable for the designated uses,” the staff reports. State officials are currently developing numeric criteria for watersheds that may be threatened by nutrient pollution.
Total phosphorus is not permitted to exceed 1 milligram per liter (1,000 micrograms per liter) in freshwater surface-water bodies in Puerto Rico that are upstream from a reservoir or in segments of surface-water bodies with drinking-water intakes or estuarine water, according to the EPA Region 2 DEPP staff. The territory currently is working to develop nutrient criteria for lakes, reservoirs, rivers, and streams using the EPA’s reference approach. Nutrient criteria currently being developed for the US Virgin Islands will be tailored specifically for the tropical ecosystems, including coral reefs and mangroves, that could be impacted directly by nutrient pollution. The territory is working with local universities to assess the nutrient impact on the ecosystems in its coastal and estuarine waters.
In Missouri, state officials like environmental specialist Mark Osborn of Jefferson City have been working with people of varied interests to set numeric standards for years.
“At this point we still don’t have a specific regulation,” says Osborn. “We’re meeting with stakeholders, including municipal people, environmental groups, agricultural groups, and academics.”
In northern Missouri, agricultural runoff is the primary source of excess nutrients, he explains, while in the Ozark region, point-source discharge typically has a greater impact.
“It’s going to be highly variable, because the EPA tries to tailor specific standards toward specific ecoregions, but it’s still kind of a broad brush,” says Osborn. “We’re trying to develop the most sensitive regional approach, seeking homogeneity within the ecoregions as we find them.”
Aesthetic issues like algae blooms resulting from excess nutrients have been a challenge, and some fish kills have been recorded. “But on the other hand, there are some with our conservation department that advocate that in some areas we need to have some nutrient enrichment to support fisheries,” says Osborn, explaining that the biggest challenge in creating the numeric criteria is creating a balance between those needs.
Region-Specific Challenges
Alaska’s geology presents some unusual challenges in this area. “Most scientists believe that most of our waters are nutrient poor, as biological inputs are limited,” explains Kent Patrick-Riley, program manager for the protection and restoration group within the nonpoint-source water pollution control section of the Anchorage-based Department of Environmental Conservation. “So we are often concerned about too little levels of nutrients. Our geology is influenced by unusual forces, which leads to a hodgepodge of nutrient levels in surface soils and waters: volcanoes and their ash; glaciers, which affect nutrients; some gouging; depositions—for example, moraines; wind-spread particulates, or loess; severe climate changes; extreme impacts from global warming; and also large seasonal influenced swings in levels.” Occasionally, the wind can carry particulates from Asia that can have an unexpected impact.
Although nutrient contamination is a relatively small concern in the state, it is being monitored. “Currently, the acceptable level of nutrients is being determined by indirect measures, such as the water-quality criteria for dissolved oxygen and narrative water-quality criteria prohibiting substances which produce nuisance aquatic life such as algal or bacterial blooms,” says Nancy Sonafrank,the section manager for the Alaska Department of Environmental Conservation’s Water Quality and Monitoring Section, based in Fairbanks. “The State of Alaska is in the process of collecting water-quality monitoring data in the Cook Inlet ecoregion that will allow development of specific nutrient criteria for lakes in that region.”
This ecoregion, which includes the western Kenai Peninsula, the Matanuska Susitna Valley, and the Anchorage area, has a variety of potential sources for excess nutrient contamination. “This area has a combination of urban development, rapid population growth, and some agricultural activity, all of which are potential contributors to high nutrient runoff,” says Sonafrank.
The nutrients that do surface in most Alaskan waters often come from salmon carcasses. “This can create aquatic ecologies quite different from other places,” says Patrick-Riley. “For example, in much of the country, the levels of chironomids [midges] are used as an indicator of biological health. Chironomids abound when there are high levels of anthropogenic-derived nutrients, so they are seen as a negative indicator.
“However, as Alaskan waters are often very nutrient poor, salmon carcasses provide critical sources of nutrients to the streams, and some species of chironomids are the main feeders on the carcasses and thereby play an essential role in adding nutrients to the system. Therefore, high populations of chironomids may be an indicator of a healthy aquatic biology in Alaska, whereas in other places they are seen as indicators of eutrophication. Research also shows that bears play a key role in distributing these salmon nutrients throughout the riparian zone.”
Climate changes also pose stormwater challenges for the region.“Because of the depth of freeze in the wintertime, melted snow cannot infiltrate, so our breakup, or snowmelt period, leads to a lot of runoff, often laden with sediment. We have to find places to store snow removed from roads and parking lots that will provide adequate treatment of the snowmelt in the spring,” explains Mel Langdon, who works in the stormwater and wetlands program, part of the nonpoint-source program at Alaska’s Department of Environmental Conservation Division of Water in Anchorage. “Because structural controls such as sediment ponds are frozen during the breakup period, the treatment they might otherwise offer is not available.”
In the far warmer climate of Florida, a state laced with and nearly surrounded by water, sources of nutrient pollution include septic tanks, leaching from landfills, and runoff from urban yards and agricultural lands. Eric Livingston of the Florida Department of Environmental Protection says the state is establishing TMDLs set up on a rotating schedule.
“Phase II MS4 [municipal separate storm sewer system] general permits typically include special conditions for discharges into impaired waters or where TMDLs have been developed. These conditions are in accordance with 40 CFR [Code of Federal Regulations] 122.44(d)(vii), which states that water-quality-based effluent limits need to comply with all applicable water-quality standards and must be consistent with wasteload allocations identified in TMDLs,” according to a statement by EPA region 2 staff members. “The permit conditions vary from state to state, but since stormwater effluent limits are usually defined as stormwater management plans, these plans need to be developed with the nutrient criteria in mind for MS4s discharging into impaired waters.”
About 200 TMDLs are currently in place in Florida, according to Livingston. Other regions also have begun to recognize the importance of TMDLs, even though the process from development through approval takes time.
“To date, Alabama has only developed and issued two nutrient TMDLs that have subsequently received approval from EPA Region 4,” says Shirley. “These are for Weiss Lake and the Cahaba River.”
Managers can evaluate their existing programs to determine where they can be modified in order to address the nutrient pollutants, explains J. Douglas Fritz, the MS4 program manager at the Virginia Department of Conservation and Recreation in Richmond.
“Some items to consider are: Does the municipality have nutrient management plans for locations in which it applies nutrients? Does the municipality store potential nutrient sources in a manner to prevent contact with precipitation? Has the municipality identified potential nutrient hotspots entering their MS4?” he says. ”Does the municipality require new development to install post-development BMPs [best management practices] that are more efficient in nutrient removal? Does the municipality review retrofit opportunities as a means of nutrient reduction?”
Vegetated filterstrips and water-quality swales, infiltration trenches and basins, rain gardens or bioretention areas, permeable pavement, and constructed wetlands are some of the BMPs that could control nutrient runoff suggested by Drinkard of New Mexico.
Encouraging better riparian cover is something Osborn specifically recommends. Educating the public about the impact of stormwater runoff is another area where stormwater managers can make a difference, explains Bell.
“Talk about excess nutrients and what will happen to them in a rain event and [what] can cause impairment of the local waterways,” he says, adding that illicit discharge detection and elimination is another area where stormwater managers can have a significant impact. “The other measure that may have some impact is construction, grading,” he says, noting that there can be some nutrients in the soil.
Municipal stormwater managers also need to question how they will “pay for retrofitting drainage systems to provide stormwater treatment,” which is, according to Livingston, the most challenging issue many face.
Identifying and replacing septic systems that have hookups to wastewater treatment plants is another way municipal stormwater managers can improve nutrient control standards, according to Powell.
“Use ordinances to control the use of fertilizers at homes, businesses, and recreational facilities,” he says. “Prohibit phosphate detergents. Establish pet waste control ordinances.”
Making these initiatives clear to the public is important.
“The education and outreach component is very important. It’s their watershed. It’s a crucial part of doing their piece,” says Quentin White, stormwater coordinator for EPA Region 5, stressing the importance of involvement. “We’re all in this together. Water doesn’t have boundaries.”
Shirley suggested educational efforts in schools would be both beneficial and recommended.
Many people do understand the need for numeric nutrient criteria, making it easier to implement, explains Bira, but there are various opinions on how these numbers should be developed.
“As with any other assessment improvement, the ones with the most at stake are the ones with the highest concentrations of pollutants. As far as current compliance levels, it is my understanding that the vast majority of municipal dischargers are in compliance,” he says. “Narrative criteria have a little more ‘wiggle room,’ and the implementation of numeric criteria is making some folks nervous.”
In New York, noncompliance with the nutrient control standards means the reported impacts could be listed on the state’s 303(d) list or the state’s list of impaired waters. In the western US, time and the number of offenses may affect this approach.
“Clearly it’s more difficult to get a water body listed in California than it used to be five years ago,” says G. Fred Lee, referring to the 303(d) list. Lee, who with his wife Anne Jones-Lee runs a consulting firm specializing in water-quality issues in El Macero, CA, adds, “It was done more off the cuff. It was a less rigorous approach. Today, they have to have a certain number of violations over a period of time to get on the list. We don’t judge that good or bad. There is some justification for that. There is a reluctance, too, by some regulatory agencies to put a water body on because they have to do the TMDLs.”
The reluctance is there because the agency may not have the resources to accomplish this.
“It’s clearly an issue that has to be considered,” says Lee. “There’s no question that nutrients are the most important cause of water-quality impairment in the country.”
As states move to implement numeric nutrient criteria, one thing sure to be sparked is conversation.
“There’s going to be resistance when they are brought up for public comment,” says Osborn. “Some will find them too strict and others will find them not strict enough.”
Brian Bell of Region 5 says that the region’s states have been very good about providing training, issuing guidance, and maintaining good relationships with agencies and environmental groups regarding the new requirements.
“The MS4 permitting program is based on an iterative process of BMP implementation. The benchmark goal of any program is to not violate water-quality standards. This would apply to any nutrient criteria as well,” says Fritz in Virginia. “Given this, municipal stormwater programs may face additional permitting requirements such as requirements for implementation of BMPs aimed at nutrient reduction and increased monitoring.”
TMDLs play a role in this process.
“Whenever and wherever a TMDL has been developed and approved by EPA, MS4s will, by way of National Pollutant Discharge Elimination System requirements, be expected to maintain the necessary BMPs to reduce TP loadings contributed from various diffuse sources,” says Shirley.
Municipal stormwater managers can make a difference by working with their state as they develop numeric nutrient criteria.
“All water pollution falls into either point-source or nonpoint-source categories. Depending on the size of the municipal area, stormwater may be either. Input from municipal stormwater managers will be a great assistance to state agencies in the nutrient criteria development process, since they result in a significant financial investment,” says Bira. “Also, any data the municipalities may have will be very useful as the states are trying to determine existing water-quality conditions.”
States may add to the requirements in order to monitor discharges to waterways as a result of the criteria changes, says Bira, and municipal programs may add more stormwater treatment or collection structures. Changes at a municipal level likely will vary depending on their geographical region.
“Generally, in the North, there are more combined systems, where stormwater is mixed with raw sewage, and all water is treated prior to discharge. In the South, stormwater is usually not mixed with sewage. The two sources are collected and discharged separately,” says Bira. “There are still many municipalities that do not treat stormwater. It is possible that these may be affected to a higher degree. And it is possible that many municipalities in the US will be required to treat wastewater and stormwater for removal of nitrogen and phosphorus. Some already do that, and they can tell you that treatment costs are increased.”
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As numeric nutrient criteria are tailored to the needs of regional water bodies, so is the opportunity for improving surface-water quality. Lee believes that to address nutrient standards, states will need to use a comprehensive approach, combining narrative with numeric criteria, and that the day will come when this will happen, though it is not clear yet in what form.
While we wait, it’s clear that creating effective nutrient standards for America’s water bodies is a primary way to ensure their healthy future.
September 2007
All in the Numbers
How and why many states continue to move from narrative to numeric nutrient criteria
Excess nutrient pollution has rallied municipal, state, and EPA officials together, working to update the criteria to improve water quality throughout the country, though the very nature of the work is moving forward in small, gradual steps.
In 1998, the EPA recommended water-quality criteria for nutrients under the Clean Water Act. The recommendation was intended to guide states and territories as to how they could develop nutrient criteria that would be more region-specific to water bodies in their areas and that could be adapted into their individual water-quality standards.
When excess nutrients, primarily nitrogen and phosphorous, in a body of water cause algae to bloom, this algae can use up oxygen needed for other aquatic life during a process known as eutrophication. The side effects of eutrophication can be a foul smell, slimy water, and, in some instances, fish kills.
There are numerous potential sources of eutrophication.
“Potential sources of nutrients include wastewater treatment facilities; septic tank–leach field disposal systems; animal feeding operations; aquaculture; agriculture; permitted runoff from confined animal feeding operations; rangeland grazing; urban runoff and storm sewers; construction sites; hydromodification; drought-related impacts, which reduces the dilution; pet wastes; atmospheric deposition; wildlife and waterfowl; and natural sources such as the geology and soils,” explains Shelly Drinkard, nutrient and lakes team leader at the New Mexico Environment Department Surface Water Quality Bureau based in Santa Fe.
“Multiple sources require multiple solutions,” says Eric Livingston, bureau chief for watershed management at the Florida Department of Environmental Protection in Tallahassee. “We’re all part of the problem, and we all have to be part of the solution.”
Defensible Measurements
While the EPA has for many years recognized the importance of controlling nutrients such as nitrogen and phosphorus as part of water-quality protection, explains Mike Bira, nutrient regional coordinator for the EPA’s Region 6, “The complicated chemical, biological, and physical interactions which determine exactly how nutrients affect individual water bodies is the subject of much study.” He says federal, state, and local entities continue to work together to create numeric nutrient criteria as part of a state’s water-quality standards. The states set water-quality standards with the intention of having them approved by the EPA.
“Basically, the way acceptable levels are determined is through the establishment of designated uses for water bodies,” says Bira. “Once uses are established, criteria are developed to protect uses. Criteria are scientifically defensible measurements to determine whether or not uses are being met.
“Criteria may be either numeric, such as ‘a minimum dissolved oxygen concentration of 2.0 milligrams per liter,’ or narrative, such as a concentration of ‘X’ cannot be at a level which causes excessive algal growth. Currently, all five EPA Region 6 states—Arizona, Louisiana, Oklahoma, New Mexico, and Texas—as well as most of the states in the US, have set narrative criteria for nutrients. EPA sees the use of numeric criteria for nutrients as much more protective of water quality.”
The narrative standard was the criteria followed prior to the EPA’s recommendation that numeric standards be established.
“To me, its pretty obvious that a hard, scientifically defensible number is much more useful in determining water-quality impairment than a narrative description,” says Bira. “There is much ambiguity in typical narrative language like ‘significant’ or ‘excessive.’ For example, excessive plant growth to a swimmer is much less than to a bass fisherman.”
Numeric criteria would serve as an equalizer of sorts that could clarify for municipalities specifically what is expected of them.
“In the 2001 guidance document, we do recommend specific numeric values, and we recommend states develop their own, too,” says Brian Thompson, the Chicago-based nutrient water-quality standards coordinator for EPA Region 5.
The states in Region 5—Illinois, Indiana, Ohio, Michigan, Wisconsin, and Minnesota—are progressing as far as developing nutrient water-quality standards, putting forth a good effort, and following the 2001 EPA recommendations, Thompson says. They reference condition criteria that identify the “water quality that is considered to be minimal impact” and set the criteria at that level, says Thompson.
“A second option is to identify some kind of relationship between nutrients and adverse effect,” he says. “In many cases [there are] a combination of those two approaches.”
Most states are communicating with local or municipal stormwater programs, according to Bira, updating them on progress at the EPA regional level.
“In my experience with our states, this has been a very open process, and if anybody feels the need to know more, access to the state staff has been quite easy,” he explains. “Our Region 6 states all have the most current information on their Web sites.”
Gary Welker, Ph.D., a Kansas City, KS–based nutrient coordinator for EPA Region 7, says a regional technical advisory group has been established to develop nutrient benchmarks for streams, rivers, and lakes. Agencies in Kansas, Nebraska, Iowa, and Missouri are working with universities in those states to build this criteria.
“This tech advisory group is using existing data, modeling, literature values, and collecting data. Ultimately these levels are to be set by the states. Currently there are these advisory groups going on in our state as well,” he says. “In our four states they will be tailoring their own criteria.”
These figures will be based on climate, topography, and geology.
“Our whole approach began with the Clean Water Action Plan, the document from Al Gore,” says Welker. “One of the action items in the action plan was to develop criteria in ’98.”
Of the Region 7 states, only Nebraska has submitted criteria for review so far, says John DeLashmit, chief of water-quality management for EPA Region 7, adding that all of the states can be characterized as on schedule for developing the numeric criteria.
“Each one of the states is taking a similar approach—lakes and reservoirs first, then streams and rivers,” he says, noting that it is easier to determine criteria for non-flowing waters. “Kansas has put in place a nutrient reduction strategy. They are planning to reduce the concentration of the amount of nutrients in waters leaving the state of Kansas by 30%. When you read their plan, they lay out exactly how they are [going to accomplish this].”
Developing Criteria for Impaired Versus Unimpaired Waters
Alabama also has taken steps to create numeric criteria for various water bodies. “The Alabama Department of Environmental Management [ADEM], with some assistance provided by state-contracted consultant Tetra Tech, remains in the ongoing process of developing numeric nutrient criteria levels for water bodies within the state,” says Stan Shirley, a senior environmental specialist in the water division of the Alabama Department of Environmental Management based in Montgomery. “Numeric nutrient criteria have already been developed for various major unimpaired lakes and reservoirs using a ‘weight of evidence’ approach. This approach relies on historically and recently collected chlorophyll a levels to establish protective site-specific chlorophyll a levels for each major unimpaired lake or reservoir.” Chlorophyll a, a blue-green pigment, can be used as an indicator of how much algae is present in the water.
Three-dimensional water-quality models that can help the department determine the appropriate nutrient levels for Alabama’s major impaired reservoirs and lakes are under development and are expected to be completed in the near future. Total maximum daily loads (TMDLs), water body–specific figures developed for individual nutrients, are part of that process.
“The development of nutrient TMDLs for 303(d)-listed or impaired rivers and streams, as well as the establishing of nutrient criteria for rivers and streams as a whole, has used a reference site approach,” says Shirley. “ADEM is also in the developmental stage of determining numeric nutrient criteria levels for estuarine and coastal waters. ADEM is an active participant of the Gulf of Mexico Alliance cooperative, which is composed of the state environmental protection agencies of Alabama, Florida, Louisiana, Mississippi, and Texas, as well as the federal government and other concerned entities whose aim is to share science, knowledge, technologies, expertise, and financial resources to better protect the health and complex ecosystem in the Gulf of Mexico.”
New Mexico’s Surface Water Quality Bureau’s Monitoring and Assessment Section worked with the EPA and the US Geological Survey to develop numeric criteria for nutrient standards in wadable streams throughout the state in the form of a nutrient assessment protocol. The threshold values presented in the protocol continue to be tested before being adopted into the New Mexico Water Quality Standards, and the process of developing similar approaches to propose nutrient criteria for other bodies of water including wetlands, lakes, reservoirs, and rivers throughout the state has been outlined for the future.
Municipal stormwater programs are inspected throughout the state, according to Richard Powell, industrial team leader at the New Mexico Environment Department Surface Water Quality Bureau in Santa Fe, as are construction areas and industrial facilities.
New York, New Jersey, Puerto Rico, and the US Virgin Islands comprise EPA’s Region 2. New York uses numerical guidance values, such as the existing ambient water-quality guidance value of 20 micrograms per liter for phosphorus that has been established for Classes A, AA, A-S, AA-S, and B waters; water body-specific values, including the target total phosphorus (TP) concentration for Lake Erie that is divided up by basin, with the Western Basin equal to 15 micrograms per liter and the Central and Eastern basins equal 10 micrograms per liter; and narrative standards to address water-quality impacts from nutrient over-enrichment, according to the EPA Region 2’s Division of Environmental Planning and Protection (DEPP) staff. The state currently is working to add numeric values for nutrients present in lakes, reservoirs, rivers, and streams, staff members report.
Similarly, New Jersey uses both narrative and numeric criteria for total phosphorus as part of the state’s Surface Water Quality Standards. For example, total phosphorus in the state’s streams may not exceed 0.1 milligram per liter unless “it can be demonstrated that total P is not a limiting nutrient and will not otherwise render the waters unsuitable for the designated uses,” the staff reports. State officials are currently developing numeric criteria for watersheds that may be threatened by nutrient pollution.
Total phosphorus is not permitted to exceed 1 milligram per liter (1,000 micrograms per liter) in freshwater surface-water bodies in Puerto Rico that are upstream from a reservoir or in segments of surface-water bodies with drinking-water intakes or estuarine water, according to the EPA Region 2 DEPP staff. The territory currently is working to develop nutrient criteria for lakes, reservoirs, rivers, and streams using the EPA’s reference approach. Nutrient criteria currently being developed for the US Virgin Islands will be tailored specifically for the tropical ecosystems, including coral reefs and mangroves, that could be impacted directly by nutrient pollution. The territory is working with local universities to assess the nutrient impact on the ecosystems in its coastal and estuarine waters.
In Missouri, state officials like environmental specialist Mark Osborn of Jefferson City have been working with people of varied interests to set numeric standards for years.
“At this point we still don’t have a specific regulation,” says Osborn. “We’re meeting with stakeholders, including municipal people, environmental groups, agricultural groups, and academics.”
In northern Missouri, agricultural runoff is the primary source of excess nutrients, he explains, while in the Ozark region, point-source discharge typically has a greater impact.
“It’s going to be highly variable, because the EPA tries to tailor specific standards toward specific ecoregions, but it’s still kind of a broad brush,” says Osborn. “We’re trying to develop the most sensitive regional approach, seeking homogeneity within the ecoregions as we find them.”
Aesthetic issues like algae blooms resulting from excess nutrients have been a challenge, and some fish kills have been recorded. “But on the other hand, there are some with our conservation department that advocate that in some areas we need to have some nutrient enrichment to support fisheries,” says Osborn, explaining that the biggest challenge in creating the numeric criteria is creating a balance between those needs.
Region-Specific Challenges
Alaska’s geology presents some unusual challenges in this area. “Most scientists believe that most of our waters are nutrient poor, as biological inputs are limited,” explains Kent Patrick-Riley, program manager for the protection and restoration group within the nonpoint-source water pollution control section of the Anchorage-based Department of Environmental Conservation. “So we are often concerned about too little levels of nutrients. Our geology is influenced by unusual forces, which leads to a hodgepodge of nutrient levels in surface soils and waters: volcanoes and their ash; glaciers, which affect nutrients; some gouging; depositions—for example, moraines; wind-spread particulates, or loess; severe climate changes; extreme impacts from global warming; and also large seasonal influenced swings in levels.” Occasionally, the wind can carry particulates from Asia that can have an unexpected impact.
Although nutrient contamination is a relatively small concern in the state, it is being monitored. “Currently, the acceptable level of nutrients is being determined by indirect measures, such as the water-quality criteria for dissolved oxygen and narrative water-quality criteria prohibiting substances which produce nuisance aquatic life such as algal or bacterial blooms,” says Nancy Sonafrank,the section manager for the Alaska Department of Environmental Conservation’s Water Quality and Monitoring Section, based in Fairbanks. “The State of Alaska is in the process of collecting water-quality monitoring data in the Cook Inlet ecoregion that will allow development of specific nutrient criteria for lakes in that region.”
This ecoregion, which includes the western Kenai Peninsula, the Matanuska Susitna Valley, and the Anchorage area, has a variety of potential sources for excess nutrient contamination. “This area has a combination of urban development, rapid population growth, and some agricultural activity, all of which are potential contributors to high nutrient runoff,” says Sonafrank.
The nutrients that do surface in most Alaskan waters often come from salmon carcasses. “This can create aquatic ecologies quite different from other places,” says Patrick-Riley. “For example, in much of the country, the levels of chironomids [midges] are used as an indicator of biological health. Chironomids abound when there are high levels of anthropogenic-derived nutrients, so they are seen as a negative indicator.
“However, as Alaskan waters are often very nutrient poor, salmon carcasses provide critical sources of nutrients to the streams, and some species of chironomids are the main feeders on the carcasses and thereby play an essential role in adding nutrients to the system. Therefore, high populations of chironomids may be an indicator of a healthy aquatic biology in Alaska, whereas in other places they are seen as indicators of eutrophication. Research also shows that bears play a key role in distributing these salmon nutrients throughout the riparian zone.”
Climate changes also pose stormwater challenges for the region.“Because of the depth of freeze in the wintertime, melted snow cannot infiltrate, so our breakup, or snowmelt period, leads to a lot of runoff, often laden with sediment. We have to find places to store snow removed from roads and parking lots that will provide adequate treatment of the snowmelt in the spring,” explains Mel Langdon, who works in the stormwater and wetlands program, part of the nonpoint-source program at Alaska’s Department of Environmental Conservation Division of Water in Anchorage. “Because structural controls such as sediment ponds are frozen during the breakup period, the treatment they might otherwise offer is not available.”
In the far warmer climate of Florida, a state laced with and nearly surrounded by water, sources of nutrient pollution include septic tanks, leaching from landfills, and runoff from urban yards and agricultural lands. Eric Livingston of the Florida Department of Environmental Protection says the state is establishing TMDLs set up on a rotating schedule.
“Phase II MS4 [municipal separate storm sewer system] general permits typically include special conditions for discharges into impaired waters or where TMDLs have been developed. These conditions are in accordance with 40 CFR [Code of Federal Regulations] 122.44(d)(vii), which states that water-quality-based effluent limits need to comply with all applicable water-quality standards and must be consistent with wasteload allocations identified in TMDLs,” according to a statement by EPA region 2 staff members. “The permit conditions vary from state to state, but since stormwater effluent limits are usually defined as stormwater management plans, these plans need to be developed with the nutrient criteria in mind for MS4s discharging into impaired waters.”
About 200 TMDLs are currently in place in Florida, according to Livingston. Other regions also have begun to recognize the importance of TMDLs, even though the process from development through approval takes time.
“To date, Alabama has only developed and issued two nutrient TMDLs that have subsequently received approval from EPA Region 4,” says Shirley. “These are for Weiss Lake and the Cahaba River.”
Managers can evaluate their existing programs to determine where they can be modified in order to address the nutrient pollutants, explains J. Douglas Fritz, the MS4 program manager at the Virginia Department of Conservation and Recreation in Richmond.
“Some items to consider are: Does the municipality have nutrient management plans for locations in which it applies nutrients? Does the municipality store potential nutrient sources in a manner to prevent contact with precipitation? Has the municipality identified potential nutrient hotspots entering their MS4?” he says. ”Does the municipality require new development to install post-development BMPs [best management practices] that are more efficient in nutrient removal? Does the municipality review retrofit opportunities as a means of nutrient reduction?”
Vegetated filterstrips and water-quality swales, infiltration trenches and basins, rain gardens or bioretention areas, permeable pavement, and constructed wetlands are some of the BMPs that could control nutrient runoff suggested by Drinkard of New Mexico.
Encouraging better riparian cover is something Osborn specifically recommends. Educating the public about the impact of stormwater runoff is another area where stormwater managers can make a difference, explains Bell.
“Talk about excess nutrients and what will happen to them in a rain event and [what] can cause impairment of the local waterways,” he says, adding that illicit discharge detection and elimination is another area where stormwater managers can have a significant impact. “The other measure that may have some impact is construction, grading,” he says, noting that there can be some nutrients in the soil.
Municipal stormwater managers also need to question how they will “pay for retrofitting drainage systems to provide stormwater treatment,” which is, according to Livingston, the most challenging issue many face.
Identifying and replacing septic systems that have hookups to wastewater treatment plants is another way municipal stormwater managers can improve nutrient control standards, according to Powell.
“Use ordinances to control the use of fertilizers at homes, businesses, and recreational facilities,” he says. “Prohibit phosphate detergents. Establish pet waste control ordinances.”
Making these initiatives clear to the public is important.
“The education and outreach component is very important. It’s their watershed. It’s a crucial part of doing their piece,” says Quentin White, stormwater coordinator for EPA Region 5, stressing the importance of involvement. “We’re all in this together. Water doesn’t have boundaries.”
Shirley suggested educational efforts in schools would be both beneficial and recommended.
Many people do understand the need for numeric nutrient criteria, making it easier to implement, explains Bira, but there are various opinions on how these numbers should be developed.
“As with any other assessment improvement, the ones with the most at stake are the ones with the highest concentrations of pollutants. As far as current compliance levels, it is my understanding that the vast majority of municipal dischargers are in compliance,” he says. “Narrative criteria have a little more ‘wiggle room,’ and the implementation of numeric criteria is making some folks nervous.”
In New York, noncompliance with the nutrient control standards means the reported impacts could be listed on the state’s 303(d) list or the state’s list of impaired waters. In the western US, time and the number of offenses may affect this approach.
“Clearly it’s more difficult to get a water body listed in California than it used to be five years ago,” says G. Fred Lee, referring to the 303(d) list. Lee, who with his wife Anne Jones-Lee runs a consulting firm specializing in water-quality issues in El Macero, CA, adds, “It was done more off the cuff. It was a less rigorous approach. Today, they have to have a certain number of violations over a period of time to get on the list. We don’t judge that good or bad. There is some justification for that. There is a reluctance, too, by some regulatory agencies to put a water body on because they have to do the TMDLs.”
The reluctance is there because the agency may not have the resources to accomplish this.
“It’s clearly an issue that has to be considered,” says Lee. “There’s no question that nutrients are the most important cause of water-quality impairment in the country.”
As states move to implement numeric nutrient criteria, one thing sure to be sparked is conversation.
“There’s going to be resistance when they are brought up for public comment,” says Osborn. “Some will find them too strict and others will find them not strict enough.”
Brian Bell of Region 5 says that the region’s states have been very good about providing training, issuing guidance, and maintaining good relationships with agencies and environmental groups regarding the new requirements.
“The MS4 permitting program is based on an iterative process of BMP implementation. The benchmark goal of any program is to not violate water-quality standards. This would apply to any nutrient criteria as well,” says Fritz in Virginia. “Given this, municipal stormwater programs may face additional permitting requirements such as requirements for implementation of BMPs aimed at nutrient reduction and increased monitoring.”
TMDLs play a role in this process.
“Whenever and wherever a TMDL has been developed and approved by EPA, MS4s will, by way of National Pollutant Discharge Elimination System requirements, be expected to maintain the necessary BMPs to reduce TP loadings contributed from various diffuse sources,” says Shirley.
Municipal stormwater managers can make a difference by working with their state as they develop numeric nutrient criteria.
“All water pollution falls into either point-source or nonpoint-source categories. Depending on the size of the municipal area, stormwater may be either. Input from municipal stormwater managers will be a great assistance to state agencies in the nutrient criteria development process, since they result in a significant financial investment,” says Bira. “Also, any data the municipalities may have will be very useful as the states are trying to determine existing water-quality conditions.”
States may add to the requirements in order to monitor discharges to waterways as a result of the criteria changes, says Bira, and municipal programs may add more stormwater treatment or collection structures. Changes at a municipal level likely will vary depending on their geographical region.
“Generally, in the North, there are more combined systems, where stormwater is mixed with raw sewage, and all water is treated prior to discharge. In the South, stormwater is usually not mixed with sewage. The two sources are collected and discharged separately,” says Bira. “There are still many municipalities that do not treat stormwater. It is possible that these may be affected to a higher degree. And it is possible that many municipalities in the US will be required to treat wastewater and stormwater for removal of nitrogen and phosphorus. Some already do that, and they can tell you that treatment costs are increased.”
As numeric nutrient criteria are tailored to the needs of regional water bodies, so is the opportunity for improving surface-water quality. Lee believes that to address nutrient standards, states will need to use a comprehensive approach, combining narrative with numeric criteria, and that the day will come when this will happen, though it is not clear yet in what form.
While we wait, it’s clear that creating effective nutrient standards for America’s water bodies is a primary way to ensure their healthy future.