[7/26/07 clarification:

In the article below, we don't mean to imply that dengue/malaria/yellow fever are currently in Northampton. However, they serve to illustrate that mosquitoes are associated with disease in general (such as West Nile Virus and Eastern Equine Encephalitis), and that excessively exposing people to mosquitoes is risky.

As the New England climate has been getting warmer in recent decades (for whatever reason), it is conceivable that problems associated with more tropical zones will become more common here. For example, last month the Boston Globe reported how the woolly adelgid has been steadily advancing north and killing trees since New England winters have become less cold. Since we’re talking about long-term issues like where to site houses, we believe that taking the long view is appropriate.

For over 350 years, Northampton builders have chosen to avoid the wetlands and buffer areas that Kohl Construction is proposing to encroach upon. We believe their wisdom should not be casually tossed aside in the name of today's hot planning craze, namely infill.]


So far we have emphasized environmental concerns and flood mitigation as reasons why it's unwise to build within 100 feet of wetlands. There's another major reason--health--as America's earliest settlers quickly discovered:

Perhaps the first Virginians to succumb to the ravages of infectious disease were the settlers at Jamestown. Mosquito-borne yellow fever and malaria took its toll on the colony’s first generation. Eighty percent of the 6,000 settlers sent to Jamestown between 1607 and 1625 died from disease, starvation, Indian attack or other causes...

The spread of epidemic diseases in Virginia and the rest of the nation was closely related to social, economic and geographical conditions, reports The Reader’s Companion to American History... Jamestown’s location on low, mosquito-ridden land was a breeding ground for disease...

Anyone who has walked around the wetlands between North Street and the bike trail can attest to its large numbers of mosquitoes in the warmer months. Kohl Construction proposes to locate 31 condo units bordering these wetlands. The American Mosquito Control Association notes the dangers of bringing people and animals into close contact with large numbers of mosquitoes.

Mosquitoes cause more human suffering than any other organism -- over one million people die from mosquito-borne diseases every year. Not only can mosquitoes carry diseases that afflict humans, they also transmit several diseases and parasites that dogs and horses are very susceptible to. These include dog heartworm, West Nile virus (WNV) and Eastern equine encephalitis (EEE). In addition, mosquito bites can cause severe skin irritation through an allergic reaction to the mosquito's saliva - this is what causes the red bump and itching. Mosquito vectored diseases include protozoan diseases, i.e., malaria, filarial diseases such as dog heartworm, and viruses such as dengue, encephalitis and yellow fever.

Environmental Health Perspectives observes that forest clearance and wetlands drainage can have complex effects on mosquito populations. Siting homes and their associated paraphernalia next to mosquito breeding areas, however, is clearly unwise. Kohl's five planned detention pools are particularly troubling as potential breeding sites.

Human activities are also crucial to transmission [of disease]. Forest clearance eliminates species that breed in water in tree holes (e.g., the forest Aedes species that transmit yellow fever) but provides favorable conditions for those that prefer temporary ground pools exposed to full sunlight (e.g., many of the Anopheles species that transmit malaria). Drainage of wetlands eliminates the marshy pools exploited by many species but can provide the open channels preferred by others (e.g., some important European vectors of malaria, and Culex tarsalis, a vector of St. Louis encephalitis). Agricultural fertilizers can promote the growth of algae and other larval nutrients, whereas herbicides may eliminate them altogether. Cisterns, pit latrines, sewage-polluted ditches, storm drains, and blocked gutters can support large populations of Cx. quinquefasciatus, an important vector of Bancroftian filariasis. Wells are often a significant source of malaria vectors. Water-storage jars and drums, cemetery urns, discarded rubber tires, buckets, pots, and other man-made containers can be prolific sources of Ae. aegypti, an important peridomestic vector of yellow fever and dengue and other species that originally bred in tree holes.

Additional factors arise from behavior and cultural traits. Daily activity patterns--work, rest, and recreation--the location of homes in relation to mosquito breeding sites, the design of buildings, the materials used to build them, the use of screens and bed nets, and many other factors can be significant...

Forest clearance. Many important malaria vectors breed in open sunlit pools. Forest clearance provides abundant new habitat for these species and is a classic cause of the emergence of malaria problems (110)...

Urbanization. In rapidly expanding urban areas, extensive water storage and inadequate water disposal can lead to disastrously high mosquito populations. The absence of cattle can promote stable transmission by forcing zoophilic species to feed on people.

Many tropical cities are surrounded by large satellite settlements that retain rural characteristics. Their dense populations promote conditions that are ideal for transmission. Infection rates in these semirural habitats are often higher than in the cities themselves...

Factors that Influence Yellow Fever Transmission

...Urbanization. The rapid growth of densely populated towns and cities throughout the tropics provides an increasingly favorable environment for epidemic transmission. Even when piped water is available, the supply is often intermittent, so reserves of water are stored in containers that are a source of Ae. aegypti. Other artifacts--buckets, flowerpots, bottles, cans, defunct household appliances, discarded tires, and many other items--can also serve as breeding sites if they accumulate rainwater...

Dengue [this discussion underscores that increasing urban density carries risks]

...Layout of cities. The layout of modern U.S. cities is based on the automobile. Population density is relatively low. Housing areas are often discrete, interspersed with shopping precincts, industrial parks, and other nonresidential land. Much space is devoted to wide roads, parking lots, and other open areas. Plot sizes are large, and the spacing between houses is often greater than in many tropical cities. The number of persons per house is smaller because couples have fewer children, and the extended family is less prevalent. All these factors limit the number of humans that are accessible to mosquitoes, thereby reducing the likelihood of epidemic transmission...

Kohl Construction condo proposal showing detention pools and proximity to wetlands:




See also:

Gazette: "West Nile buzzing in the city: Mosquito tests positive for virus in Northampton" (8/21/08)
...The DPH announced Wednesday afternoon that a mosquito trapped in Northampton on Sunday, Aug. 17, has tested positive for West Nile. The test comes on the heels of a host of positive West Nile tests in mosquitoes and crows in several communities throughout the month of July and August...

...for the first time this week the state has confirmed a positive mosquito sample of eastern equine encephalitis in the town of Carver...

[West Nile] can be fatal to humans - some 124 people in the United States died from it last year, according to the National Institutes of Health...

Aedes vexans [emphasis added]
Aedes vexans can be found in many different habitats. Among these are: open rain pools, tire ruts, stormwater management facilities (this includes detention, retention and infiltration basins), dredge spoil sites, salt marsh impoundments, ditches, areas in which streams or creeks have flooded over their banks, flooded woodlands, around the edges of semi-permanent swamps and bogs that are subject to some drying down, and woodland pools or any type of temporary rain pool. Larvae do not seem to exhibit a marked preference for either sunlight or shade within these habitats. Ae. vexans is a serious nuisance pest. Females will feed in shady places during the day; however, they are very active [at] dusk and vigorously seek blood meals at this time...

Culex quinquefasciatus "House Mosquito"
Culex quinquefasciatus mosquitoes are common in urban and suburban communities as well as on rural premises. They readily breed in storm sewer catch basins, clean and polluted ground pools, ditches, animal waste lagoons, effluent from sewage treatment plants and other sites that are slightly to very eutrophic or polluted with organic wastes. Development from egg to adult is temperature dependent; requiring 8 to 12 days in summer. After blood-feeding, females may return to the same or nearby larval habitats to oviposit and are often considered non-migratory mosquitoes. However, females may travel considerable distances from resting sites to search for blood hosts, and marked females have been shown to travel up to one half mile in a single night.

EPA: Do Stormwater Retention Ponds Contribute to Mosquito Problems? [emphasis added]
...Reducing our reliance on stormwater ponds for runoff control is another way to reduce potential mosquito breeding habitat. More people are turning to alternative non-structural techniques, such as rain gardens, bioinfiltration, infiltration, and vegetative swales, that slow down water and help it infiltrate without extended periods of ponding. These techniques are successfully minimizing or eliminating the need for stormwater ponds or significantly reducing the pond size requirements. Care must be taken to ensure that these alternative controls drain all standing water as designed over the years.

Similarly, efforts to reduce the amount of impervious surface in communities can reduce the need for stormwater ponds. Narrower streets, sidewalk-less communities, and elimination of cul-de-sacs are just a few of the ways that communities are now reducing the need for stormwater controls. That is not to imply that stormwater ponds can be eliminated easily. Retention/detention ponds use less space than many other types of stormwater controls and are often found to be the best and cheapest way to control runoff--especially when flooding is a concern.

Mosquito proliferation in stormwater ponds is a concern, especially when so many wet and dry ponds are in place and continue to be installed across the country. Many ponds are not properly maintained, particularly in cases where they are installed in subdivisions and other developments where the entity responsible for long-term maintenance is not clearly defined once the construction is complete...