Report: Calif. nitrate contamination spreading

[haikuman]

As a former Californian I am sad to see this problem.

By GOSIA WOZNIACKA | Associated Press – 2 hrs 15 mins ago

http://news.yahoo.com/report-calif-nitra...06496.html

FRESNO, Calif. (AP) — Nitrate contamination of drinking water is a pervasive problem in California's agricultural heartland and is bound to intensify in the coming years, according to a University of California, Davis study released Tuesday.

The study, ordered by the state Legislature, shows chemical fertilizers and livestock manure are the main source of nitrate contamination in groundwater for more than 1 million Californians in the Salinas Valley and parts of the Central Valley.

While nitrate problems have been known for decades, the study offers a comprehensive assessment of how many people are exposed and identifies solutions and costs.
"In the near future, this problem is going to persist and is likely to get worse," said Thomas Harter, UC Davis groundwater hydrologist and the study's lead author. "Even if we were to eliminate all the sources of nitrate that we have today, we would still be dealing with this issue."

[JEBB]

Is it nitrates or nitrites that are a potential problem?

[cbelt3]

A desert is 'designed' by nature to hold water as much as possible in the soil. When you irrigate a desert, it will also hold the stuff the water carries. Not a surprise. 'Groundwater" is a polite way of saying 'runoff and seepage' from irrigated areas.

There are always unforseen results when one pulls too much water out of the ground or artificially adds water to a watershed.

[haikuman]

More than you ever wanted to know about Nitrates . . . *(:>*

http://en.wikipedia.org/wiki/Nitrate

Marine toxicity


Sea surface nitrate from the World Ocean Atlas.
In freshwater or estuarine systems close to land, nitrate can reach high levels that can potentially cause the death of fish. While nitrate is much less toxic than ammonia or nitrite,[11] levels over 30 ppm of nitrate can inhibit growth, impair the immune system and cause stress in some aquatic species.[12] However, in light of inherent problems with past protocols on acute nitrate toxicity experiments, the extent of nitrate toxicity has been the subject of recent debate.[13]

In most cases of excess nitrate concentrations in aquatic systems, the primary source is surface runoff from agricultural or landscaped areas that have received excess nitrate fertilizer. This is called eutrophication and can lead to algae blooms. As well as leading to water anoxia and dead zones, these blooms may cause other changes to ecosystem function, favouring some groups of organisms over others. As a consequence, as nitrate forms a component of total dissolved solids, they are widely used as an indicator of water quality.

Nitrate also is a by-product of septic systems. To be specific, it is a naturally occurring chemical that is left after the breakdown or decomposition of animal or human waste. Water quality may also be affected through ground water resources that have a high number of septic systems in a watershed. Septics leach down into ground water resources or aquifers and supply nearby bodies of water. Lakes that rely on ground water are often affected by nitrification through this process.

Nitrate in drinking water at levels above the national standard poses an immediate threat to young children. Excessive levels can result in a condition known as "blue baby syndrome". If untreated, the condition can be fatal. Boiling water contaminated with nitrate increases the nitrate concentration and the potential risk.

Nitrate toxicity in livestock

Nitrate poisoning is a concern for cattle producers primarily, but also for other ruminant growers. Nitrate is naturally consumed by growing plants; however when growth is interrupted, the roots of plants will continue to provide nitrate from soil, and unless new plant growth occurs, the nitrate will accumulate. Thus, harvesting after nitrate buildup results in a crop that is high in nitrates. Factors that can cause nitrate buildup in plants are frost, hail damage, drought, hot dry winds, pesticide damage, herbicide damage and any other plant stunting environmental causes.[14]

Symptoms of nitrate poisoning include increased heart rate and respiration; in advanced cases blood and tissue may turn a blue or brown color. Feed can be tested for nitrate; treatment consists of supplementing or substituting existing supplies with lower nitrate material. Safe levels of nitrate for various types of livestock are as follows:[15]

[particleman]

JEBB wrote:
Is it nitrates or nitrites that are a potential problem?

In natural water, nitrate (NO3) is the predominate form. Nitrite (NO2) concentrations are typically found to be at levels less than 0.01 mg/L or ppm. The nitrite is readily oxidized to the NO3 form.