From High Salvington Mill Trust

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Translated from the Dutch using Google Translate from [1]. In the Netherlands they have created the Molenbiotoop as a means to evaluate the impact of environmental changes on a wind or watermill and have used this as the basis for legislation to protect the environment of a mill from changes that would impact on wind or water flow to a mill.

The mill biotope

Mills are never randomly located. The mill type that is found says something about the history of the landscape. Within that landscape, the mill location was chosen in such a way that the mill could function optimally. The environment to which a mill is related is called the mill biotope. A good mill biotope is fundamental to the operation and maintenance of the mill.

For the miller, good windage is crucial - and for a water miller, that is an adequate water supply. But that's not all. Windmills form a characteristic - and uniquely Dutch - landmark in many a townscape or landscape. And due to the historical interaction between mill and landscape, the mill biotope is also of great cultural-historical importance.

A good mill biotope allows a mill to be in regular operation. A rotating mill requires considerably less frequent (and therefore expensive) maintenance than a stationary mill!

What is a mill biotope?

To illustrate the close relationship between a mill and its environment, Mr. E. Smit jr. In 1973 the concept of a windmill biotope. In the meantime, this has become fully established in the windmill world. Smit derived the term from bird protection. There, the biotope represents the environment in which a particular bird species lives and thrives best. In the mill biotope, the space that is kept free for good wind catches is crucial. In addition, the visibility of the mill is central. It has grown so historically and makes a mill often so atmospheric. In a water mill, the mill biotope consists mainly of the streams that supply and drain the water, and any reservoirs.

A mill is never randomly placed in the landscape: there is always a good reason for it. A polder mill is located at a place where water must be pumped out. This is usually along a reservoir, in or near a polder. Corn and industrial mills were built in places where the supply possibilities of raw materials and the market outlets for the product were favorable. A water mill was located where an adequate water supply for the drive of the water wheel could be guaranteed. There is therefore a historical interaction between a mill and the surrounding landscape in various ways. Polder mills have even been indispensable for its creation in reclaimed land. The project to restore the mills and the 17th century landscape in the polder De Schermer is a good example of this.

The experience of the windmill

A miller experiences his mill primarily as a tool. In this capacity, the mill sets specific requirements for maintenance and the environment. Millers therefore strive to protect the mill biotope from that perspective. The emphasis has always been strongly on securing adequate windage. This is indispensable for turning and grinding with the mill. However, almost everyone else experiences a mill from the outside. It is a landmark in a village, city or landscape. The striking role that the mill plays in the landscape is appreciated by many people. This appreciation is a good basis for obtaining support for the preservation of the windmill biotope. In the past, the mill world paid too little attention to this. That is a shame, because good wind conditions and good landscape integration largely go together. The desired openness of the landscape not only serves a good windage, but also guarantees the original, striking position that the mill has traditionally occupied in the landscape. Precisely because of its scenic value, the mill can count on broad support. This support can be broadened and deepened by informing people about the history of the mill biotope and its importance for the functioning of the mill. In a crowded country like the Netherlands, complete openness of the landscape is rarely feasible. The aim is to achieve a situation in which the mill is a key element in the landscape without compromising other important landscape aspects. The search is for an acceptable compromise. If we succeed, the mill biotope will have many allies.

The biotope of the windmill

An unimpeded supply and discharge of wind is vital for a windmill to run properly and safely. We call this the windage of the mill. If there are obstacles in the area, this hinders the windage: the wind loses speed and becomes more turbulent. If the wind is obstructed too much, the mill is doomed to a stop. In fact, this is a form of capital destruction: a mill that is no longer running is more likely to decay. If a mill is in regular operation, the (voluntary) miller takes care of the daily maintenance. This means that large, costly restorations (usually publicly funded) are required considerably less often.

Need for good windage

In order to run a mill properly (and safely!), An unimpeded supply and discharge of wind is vital. In addition, millers usually do not run their mill alone: ​​it is actually used for milling. To drive the millstones or to pump water, the mill needs a certain power. A slight decrease in wind speed already results in a significant loss of power. Ten percent less wind results in more than 25 percent reduction in grinding power! At least as problematic is that the wind becomes more turbulent as a result of obstacles: more gusts and wind stills occur. This causes an uneven load on the vane cross. The grinder will run unevenly, which makes grinding almost impossible. It also leads to an increased risk of breakage of the moving parts in the mill. In addition, an irregular course in a flour mill results in poor quality flour. For safety reasons, it is important that the miller has an unobstructed view of the sky during grinding. He must be able to spot approaching showers and changes in the wind in time, in order to adjust the rotation of the blades accordingly.

Add to all this that the influence an obstacle has on the wind extends in height to twice the obstacle height over a distance of tens of times the obstacle height. It will thus be clear that a mill needs a lot of space to be able to continue operating.

Acceptable obstacle height: rule of thumb and current standards

How do we determine which obstacles in the vicinity of a mill are (will) be acceptable? As early as 1946, De Hollandsche Molen established a practical standard in the so-called 1: 100 rule. This rule means that every 100 meters further from the mill an obstacle may be one meter higher. The first 100 meters must be free of obstacles. (And with a scaffolding mill, the obstacles within that distance may not exceed the scaffolding). Obstacles more than 400 meters from the mill are no longer considered a nuisance. In a built-up environment, the 1: 100 rule is nowadays unfeasible. That is why new standards were developed by De Hollandsche Molen in 1982. To determine the permissible obstacle height in relation to the distance to a mill, Dr. ir. A.C.M. Beljaars in the 1980s to conduct a scientific analysis. His study provides an overview of the effects of obstacles on wind currents, outlined in terms of wind profiles, streamline patterns, surface roughness, and degree of turbulence. The results of his research form the basis for the biotope formula. This is used nationally as the standard for calculating the acceptable obstacle height.

The biotope formula: the current standard

Calculate the height or the distance to an obstacle yourself with our online windmill biotope calculation module.

The biotope formula is a simple way to calculate the maximum acceptable height of obstacles around a mill, in such a way that the mill does not suffer insurmountable nuisance. The biotope formula is therefore mainly used to determine whether or not an obstacle at a certain distance from the mill is "too high" or not. The first 100 meters must be free of obstacles. From 100 meters an ascending line applies that can be determined with the following formula.

H (x) = x / n + c * z

in which: H (x) = maximum allowable height of an obstacle at a distance x (in meters) x = distance from an obstacle to the mill (in meters) n = a constant, depending on the roughness of the environment and the maximum permissible wind reduction. The following values ​​are used for this: 140 for open, 75 for rough and 50 for closed area. c = a constant, depending on the maximum permissible wind reduction, usually with the value 0.2 z = height of ash (half of length fled + possibly the height of the belt, mountain or scaffolding)

If one wants to calculate the distance over which an obstacle of a certain height may be placed, the following rewritten formula is more practical.

X = n * (H (x) - c * z)

The two constants used in the above formulas require further explanation. They are related to the maximum permissible wind reduction at which a mill can still be in operation without major problems. With a reduction of the wind to 95%, the power of a windmill decreases by 14%. An even greater wind reduction quickly results in a 25% reduction in windmill power. This threatens to create an unworkable situation. The commonly used values ​​for the constants are based on a compromise. As a starting point, a maximum permissible wind reduction of 5% has been chosen. This value is included in the constants n and c.

A second factor to consider is the "roughness" of the surface around the reel, which affects wind speed. At a few meters above a rough surface, such as plants or buildings, the wind speed is halved compared to a reference height of 60 meters. Above water, the least harsh environment, this decrease is only about 20%. In the biotope formula, the option is given to enter a value for the constant n, depending on the roughness of the environment. The higher the roughness of the environment, the lower the value that must be entered for this.

The three roughness categories are as follows.

Open: Flat land with only superficial vegetation (grass) and sometimes minor obstacles. For example runways, pasture without windbreaks, vacant arable land.

Rough: Arable land with alternating high and low crops. Large obstacles (rows of leafy trees, low orchards, etc.) spaced about ten to fifteen times their height. Vineyards, cornfields and the like

Closed: Floor regularly and completely covered with fairly large obstacles, with spaces in between no greater than a few times the height of the obstacles. For example, forests and low-rise buildings.

The calculation can be further refined by observing the biotope on site and inventorying the roughness of the terrain in different directions around the mill. For example, with a mill on the edge of a village, a certain sector may be "open", while the village side is "rough" or "closed". In that case, several calculations have to be performed to determine the acceptable obstacle height.

As mentioned, different rules apply to the first 100 meters around the mill. It has been found that the disturbance of the wind directly behind an obstacle is very great. For ground sailers, the first 100 meters must therefore be completely free of buildings or plants, while the obstacles in a belt, mountain or scaffolding mill must in any case not exceed the belt, mountain or scaffolding. From 100 meters, the maximum acceptable height is an ascending line that is calculated using the biotope formula. When the environment of a mill meets these requirements, this is a permissible situation. Everything above the line should be viewed critically. With strict application of the biotope formula, it may turn out that obstacles that remain below the scaffolding height around a scaffold mill are also not acceptable, even at a distance of more than 100 meters. Theoretically that is correct. As explained elsewhere, the influence of an obstacle reaches approximately twice its own height. In practice, however, this is difficult to sell. In practice, it is therefore assumed that anything that is not higher than the rack height is acceptable.

In practice, the biotope formula for a ground sailor in an open area roughly results in the aforementioned 1 in 100 rule. This means that every 100 meters further from the mill the obstacle may be 1 meter higher. This is only really feasible in an open polder landscape. The application of the formula is a first approach, which should be followed by a more precise assessment when the standards are exceeded. A farm to be built with a ridge height of 10 meters would then have to be about a kilometer from the mill. In such cases, it is advised to lodge an objection if new construction takes place within 400 meters of the mill. In an urban, closed area, a conversion to such a rule of thumb is not possible, because the influence of the ash height of the tower mill, belt mill or mountain mill leads to different results.

The calculation examples given below demonstrate this. Mapping the quality of the biotope, Laméris method Factors influencing windage.

Biotope protection: inventorying the space around the mill

In order to be able to protect the windmill biotope and to be able to make the negative effects of obstacles clear to others, the situation must be properly mapped out. The collected data is preferably entered on the cadastral background. Such a map is also available in digital form at the Land Registry. With the mill as the center point, circles of 100, 200, 300 and 400 meters are drawn on this map. The maximum acceptable obstacle height is calculated for each circle using the biotope formula. Broadly speaking, this is the area in which developments must be carefully monitored.

A number of things need to be inventoried within this area. An up-to-date inventory makes quick action much easier. You can think of the topographical situation, the allotment, a list of owners and users of surrounding plots, the type of land use, existing trees by type, current height and potential height, existing buildings with height, regulations in the zoning plan, the choice of a water board. The height of the building can be determined by estimating the height on site or on the basis of the building permit granted.

An important additional development is the digitized inventory of the windmill biotope with the help of the Current Altitude File Netherlands (AHN). We call this the Laméris method.

The Laméris method and the Current Altitude File Netherlands: the quality of the biotope digitally mapped

Making a good inventory of potentially annoying objects around a windmill is an extensive and difficult job. Distances and heights of sometimes a large number of objects must be mapped and tested against the biotope standards. Partial automation of this process can give a better grip on the problems surrounding a mill. Moreover, such a method makes it possible to objectively compare the biotope of different mills in an area. In this way it can be determined which mills require extra attention.

The most promising method in this regard is the "Laméris method", which is based on the so-called Current Altitude File Netherlands (AHN). This consists of nationwide elevation data that can be ordered online for a fee. During his study geo-information science, Evert-Jan Laméris, himself a volunteer miller, came into contact with this information. He was the first to use the information from the AHN to make an inventory of the quality of the windmill biotopes in Drenthe. The method, which was subsequently also applied to all windmills in North Holland, works as follows. A zone of 400 meters is mapped around each mill using data from the AHN. The elevation data shows the presence of tall objects, such as trees and buildings, that cause wind nuisance. The elevation data in the mill biotope is analyzed using the biotope formula. Some important characteristics of the mill are also used (blade length and any rack height). The analysis leads to a map showing the height measurements that exceed the biotope standard. The degree of exceedance is more serious the more a measured obstacle rises above the biotope standard. The severity of the violation is visualized by colors. The data is then ordered into sectors (50x50 meters), whereby the tallest building or the tallest tree is a measure of the quality of a sector. A score can be determined for the eight major wind directions. To this end, the individual scores of the sectors in the eight major wind directions are categorized and added together. The Laméris method is a big step forward, because it leads to an objective assessment that makes the biotope of mills mutually comparable. However, a final assessment is never possible without an assessment in the traditional way "in the field". Finally, the ratings should therefore be compared with ratings traditionally made by millers or biotope keepers. This involves looking in the field in the eight major directions of the compass and preferably also using photos to record what kind of obstacles are around the mill. The AHN makes no distinction here. The very important influence of obstacles on the amenity value can also only be assessed in the field.

The Laméris method can also be helpful in determining in advance the effect of a new construction project or the construction of green areas relatively easily. In the event of relocation of the mill, the expected quality of the biotope can be estimated in advance. In the long term, the aim is to record the protection zone of every windmill in the Netherlands in this way and to make the information usable for management purposes. You will find further information about the Laméris method via the link addresses.

Factors influencing windage

Objects that influence windage can be divided into two categories: buildings and plants. Both have their specific consequences for the mill biotope.


The most common threats, both in and around urban areas and at village expansions, are high-rise buildings such as residential apartments, offices and industrial halls. These literally take the wind out of its sails. For example, it may happen that a polder mill is now in the middle of an urban district and, in addition to a greatly reduced windage due to the visual damage to the mill environment, the amenity value has also decreased significantly. The problem with buildings that are too high is that it causes wind turbulence, a rapid variation in wind speed, and has a damaging effect on the mill due to the irregular wind gusts. It is more difficult to work with the mill and the quality of the product is compromised. Due to the unequal load on the vane cross, increased wear occurs on the going work. In the worst case, this can lead to the breaking of a rod or the axle head. This creates a dangerous situation and usually leads to even greater damage to the reel body.

Provisions about buildings and use are laid down in the planning regulations that accompany the zoning plan. This clearly indicates where which type of building may be located. Often the maximum gutter and ridge heights are indicated here. If a windmill protection zone is included in the zoning plan, it will be clear that the maximum permitted ridge heights of the buildings at different distances from the windmill follow from the biotope formula. Mill owners are nowadays increasingly confronted with the offer to buy off the negative effects on the mill biotope. The change in the mill biotope sometimes also gives rise to changes to the mill itself. Dike elevations or new buildings were and are regularly a reason to raise a mill. Sometimes this is done by placing the mill on a pedestal, as it were, such as the Waardenburg mill. Sometimes by raising the mill itself, such as the Edens mill in Winschoten.


For the windage and the free view of a windmill, it is important that the plants in the vicinity are not too high. This does not only concern trees along roads and in gardens, or natural forests. Under an agricultural destination there is often the possibility to plant production forest. This is of course not desirable close to the mill. Trees usually only cause wind nuisance over the years. Other plants can also hinder the wind through neglect or unfamiliarity with the consequences of the owners.

The risk that wind nuisance will arise in the future also depends in part on the tree species. Poplars and willows, for example, are fast-growing species that can cause wind nuisance within a few years. Other species, such as linden and fruit trees, grow less quickly and often remain lower. Unfortunately, people often opt for 'fast green' and too little thought is given to the consequences in the medium term. There are various possibilities to prevent annoying plants or to have them removed. It is best if provisions for this are included in the zoning plan. This is preferably done in the form of a mill protection zone. A construction permit system or usage rules can also be included in the zoning plan.

Apart from the possibilities offered by the zoning plan, a green plan or development plan can be drawn up with the owners of the green space. Such a plan establishes where plants will be preserved, removed, replaced and planted. The interests of all those involved and the history of the planting are taken into account. This creates support among local residents. This does require a careful weighing of interests. When a tree determines the image of the mill biotope, its preservation can also be defended for landscape reasons. In any case, it is important that the planners commit themselves jointly to the implementation of the plan.

Here are some examples of this approach.

  • Collaboration between different parties
  • Management plan "green" around the mill
  • Boom height reduced below the rack height
  • Action against trees that are too high
  • Municipal initiative to restore the mill biotope
  • Step-by-step plan to tackle tall trees

The watercourse of a polder mill

In the case of polder mills, in addition to the need for good wind catch, it must also be ensured that the mill has sufficient 'tasting'. This means that the paddle wheel or the mortar that carries the water, reach into the water. Everywhere in the Netherlands, the average water level has been lowered further and further over the years for the benefit of agriculture. The soil of peat polders in particular is also sinking further and further. This can cause the paddle wheel or auger to run dry, causing the mill to lose its function. If the water in a polder has to be raised to such an extent that the mills are in a mill alley, it will be clear that all other mills will also lose their function when the lower mill dries up.

In most cases the level reductions are inevitable. There are a few possibilities to keep a mill in operation. Usually, adjustments to the mill itself are possible. The tasting of a mill can sometimes be improved by enlarging the paddle wheel and placing it lower if necessary, or by replacing it with a auger that can lift the water from greater depth. However, these are major changes. If a jack is present, it can be seen whether it can be extended.

However, there are practical limitations to the head. A costly alternative is to add a new mill as a lower mill. Fortunately, there are still many polder mills that have retained their function in one way or another. Many mills are kept operational to be able to serve in emergencies and to assist the motorized pumping stations.

Completely independent of the height of the water level, the backwater course, along which the water flows to the mill, should be as free as possible of plants and other things that could jam the mechanism. Even a small piece of wood passing the trash gate can jam the auger or paddle wheel and cause significant damage to the wheels.

What is a water board certificate and how does it help to protect the biotope of a polder mill?

The biotope of the watermill

Because water mills depend on running water, they only occur in very specific places in the landscape. (By watermill we mean a mill that is powered by water, not a windmill that moves water.) Depending on the type of wheel they are equipped with, they make their demands on the water supply. Regardless of the wheel type, most water mills have dried up over time and are usually demolished. In that respect, the situation is considerably less rosy than with wind turbines. Nowadays there are only about a hundred water mills left in the Netherlands. It is hopeful that work is being done in various places on the restoration of streams, such as at the Kilsdonk mill. Here and there, the installation of a weir again provides mills with sufficient propulsion.

   Need for a good water supply
   Water and dam rights
   Calculation of the water requirement of a water mill

Need for a good water supply

A watermill depends on the presence of running water. Two aspects play an important role in this: the amount of water, and the drop (difference in height) that can be reached at the mill. The amount of running water and the regularity with which it is available throughout the year depend on the condition of the terrain, the relief and the size of the catchment area that drains into the mill stream.

Depending on the water supply and the slope, different types of water wheels were installed. Watermills are thus classified into four types:

   overshot mill, small wheel, diameter 2 to 5 meters.
       The water is led from a reservoir via a gutter above the water wheel. The wheel turns due to the weight of the falling water.
   medium-stroke mill, medium-sized wheel, diameter 5 to 7 meters.
       The water is directed against the centre of the wheel. The water wheel rotates due to the weight and the flow speed of the falling water.
   undercut mill, large wheel, diameter up to 9 meters.
       The wheel is moved solely by the flow speed.
   turbine mill.
       The turbine (a water wheel rotating in the horizontal plane) is driven by the flow speed of the water via a system of guide channels. At the beginning of the last century, the turbine replaced the old vertical water wheel during modernisations

If the course of a brook is moved, the mill on the former brookcourse will of course come to a standstill. But traditionally, mills were also built in places where the water supply was hardly sufficient. For this reason, especially at upper and mid-swing mills, one finds reservoirs or Wijers, in which the water was stored. In this way, they always had enough water to grind for a limited time. Often the water supply has decreased further over time. In such cases, mill guards aim to regulate the water supply and storage in such a way that the mill can grind for at least two hours a day.

Not only a minimal water supply, but also a certain slope must be maintained. The fall was sometimes artificially increased by placing a weir in the water. This gives the water sufficient speed to set the wheel in motion. If the weir level is lowered, for example because the weirs disappear in the context of stream normalization, the water mill loses its grinding function.

It is increasingly common that the streams that provide a reservoir with water supply less and less water as a result of more extensive construction, infrastructure and the construction of sewers. For example, the large-scale extraction of soil water from the Veluwerand Arnhem-Apeldoorn-Hattem resulted in the many water mills, which were adjacent, becoming dry and demolished. Using a few formulas, it is possible to calculate how large the water supply and the storage capacity of the Wijer must be in order to keep the mill running.

If the water supply has not stopped completely, the reservoir can be enlarged if space permits. Reservoirs, however, silt up quickly. Regular deepening is therefore necessary. It is one of the recurring points of attention in the maintenance of the mill environment. Furthermore, in order to be able to weir near a mill in a responsible manner without causing flooding, the junction and the associated weirs must be maintained. The use of the water in a brook and the right to prop it up has traditionally been regulated by water and dam rights.

Water and dam rights

Based on an article by W.F.A. Heemskerk, entitled Old mill and dam rights. Relics of realia minora. (Journal of Water Management History No. 1 May 1992, pp. 15-24).

Water and dam law are understood to mean the right to use the water in a stream, or the right to push it back. In addition, we have traditionally known mill law: the right to establish or maintain a water mill. A mill can have mill rights without a dam, while the reverse is also possible. While wind law no longer has a valid legal basis nowadays, this still applies to mill, water and dam law.

"The essence of the operational management of water mills is that the desired passage of the water takes place via a dam located in the water at the mill with at least two locks, namely a grinding lock and a discharge lock. When erecting the grinding sluice, the water flows on or against the water wheel; the discharge sluice carries the water around the waterwheel, if pumping is taking place or if the current has a too high water level. "

From the river or stream, the water is fed to the mill via a dug mill branch, possibly with a mill pond. The actual course of the river in the vicinity of the watermill is called a junction branch. The necessary fall is obtained by lowering the lock gates in such a way that the water is pushed upstream. Over time, the province and / or water boards have taken mill level decisions with regard to almost all water mills and their weirs. In addition, the artificial pushing of the water was offered at a maximum height. This often had consequences for the old mill and dam rights. Incidentally, it is also legally possible to maintain a minimum level in addition to a maximum backwater level.

Mill and dam duties can be canceled by:

   To renounce. The entitled party informs the competent authority in writing that he no longer wishes to make use of his mill and dam right.
   Redemption / purchase. The Midden Limburg water board and the Geleen-Molenbeek water board have bought off various dam rights in the past.
   Mixing. This is the case when the water owner acquires the ownership rights.
   Expropriation. This is only possible in conjunction with the relevant part of the power and the mill itself, of course against compensation.
   Failure to exercise the right. In principle, a mill and dam right may lapse if it is not used if the mill has not been in operation for more than 30 years. However, this must first be proven.

Calculation of the water requirement of a water mill

If one wants to keep a watermill in operation, it must be ensured that it can continue to have sufficient absolute water power. To this end, a sufficient fall and an adequate water supply must be maintained.

The absolute power of a water mill can be calculated with the following formula:

Pa = (Q * g * a * H) / 735 (in Pk) (formula A)

Pa = the absolute power of the water Q = water supply (m3 / s) g = specific weight of water (1000 kg / m3) a = gravitational acceleration (9.8 m / s2) H = drop, difference in height between fore and aft water (m)

If you want to grind with a couple of stones, you need a useful power (Pe) of 20 to 25 HP, depending on the size of the milling stones.

The efficiency of the water wheel type can be read from the table below.

 useful effect π

Overshot wheel 0.65 Center stroke wheel old type 0.5 improved type 0.6 Undershot wheel old type 0.3 improved type 0.6

The absolute hydropower capacity can be calculated as follows:

Pa = 1 / π * Pe (formula B)

π = efficiency of the water wheel type.

If the standard is set that the watermill must be able to grind for at least two hours a day, then it can be calculated how large the volume of the reservoir should be for a certain supply of the stream. A calculation example

1. Determine the required hydropower capacity using formula (B) e.g. for an overshot wheel and a desired power of 25 Pk, Pa = 38.46 Pk

2. In formula (A), H is fixed for the relevant mill. Pa has been calculated at point 1. so that Q can be calculated from the following formula:

Q = (Pa * 753) / (g * a * H) m3 / s (formula C)

Suppose H = 3.5 meters for the sake of convenience, we take g = 1000 kg / m3 and a = 9.8 m / s2 Then it follows from the formula for Q = 0.84 m3 / s

3. We use the following formula to calculate the content of the reservoir:

I = Vw - Qm * t = (Q - Qm) * t
I = Content reservoir in m3
Vw = Water consumption in grinding during the time t is Q * t
t = Duration of grinding, e.g. 2 hours> t = 7200 sec.
Qm = Water supply of the mill stream in m3 / t

Information about the water supply can be requested from the water board in which the mill stream is located.

The minimum content of the reservoir in this example should be: Q * t = 0.84 * 7200 = 6048 m3 - the amount of water required to grind for 2 hours. If we have a round pond of 1 meter deep, the diameter should be 88 meters.

The cultural-historical value of the mill biotope

The area that directly affects the windage of the mill is an important part of the mill biotope. However, the mill biotope goes much further than that. It also includes the cultural-historical interaction between the mill and its surroundings. The special location of a mill, striking, easily accessible but sometimes far from the built-up area, is a wonderful starting point to consider the role of that mill in the landscape. The mill is then the ideal place to keep the story of the landscape development visible and alive.

Wood sawmills, located on the water to enable the supply of wood, illustrate a story of industrial development in the Golden Age. The Veluwe water mills with their sprinkling system tell the story of the paper industry. In an area such as De Schermer or near Kinderdijk, the windmills are elements that represent the hydraulic history of the entire area. They are closely linked to the system of waterways, dikes and polders. Some developments do not pose a direct threat to the windmill biotope in a narrow sense. Yet they sometimes damage the landscape of which the mill is part. It is important to keep a close eye on the interests of the mill in such situations as well. How can developments be incorporated into the landscape without affecting the historical value of the landscape? As part of a much larger cultural-historical complex, a mill can be of great value. A good example of such an approach is the restoration of De Schermer.

Biotope care

The linchpin for successful biotope care is formed by local efforts. Effective action to preserve and improve the windmill biotope is best taken directly, at the local level. There is knowledge of the concrete situation, the problems and the possibilities. Developments can be closely monitored there. There, the interests of the mill can be promoted at an early stage and solutions can be sought in consultation with all parties involved. Only there can actions count on the indispensable support from the local population.

In order to properly protect the windmill biotope, initiatives must be developed in various areas.

Biotope monitoring: identifying local developments

It is very important to connect and keep all people involved in the mill, whether millers, owners, biotope guards or foundation administrators, in contact with each other. They all have their own network and can inform each other in good time about developments around the mill. A good division of tasks and mutual agreements are essential in this regard. In this way you avoid division in the windmill field and the interest of the windmill is clearly identified and at the right time.

Millers and mill owners must monitor the mill biotope closely. One must constantly be alert to building plans and other events in the environment. Within the set deadlines, request access to plans for changes within the area surrounding the mill. Also request access to the applicable zoning plans and the motives for deviation and / or exemption. Questioning with officials, advisers and administrators is often necessary.

The local press is an important tool to signal developments around the mill. However, contacts with local administrators or municipal officials often already provide information about plans in the preparatory phase. When a working group or sounding board group can participate in this phase, the possibilities for influencing the outcome are greater than in a formal decision-making procedure.

Yet it is often impossible to avoid participating in formal consultation and objection procedures. This requires some knowledge of the rules and procedures. A lot of experience has been gained around some mills, while no changes have occurred in the vicinity of other mills for years. In the latter case, it is useful to make use of the knowledge and experience of others. The provincial support centers can help you with this.

If the windage and the view of a mill threaten to deteriorate, one should immediately contact the Departmental Board of the Guild of Voluntary Millers. If necessary, this board seeks cooperation with other windmill organizations and institutions in the field of landscape, cityscape, and so on.

Support from local residents

Those who want to preserve monuments have the best chance of success when many people recognize their cultural-historical and monumental value. This is even more the case for the mill and its biotope. A mill makes demands on its environment that easily conflict with other interests. Moreover, the requirements for a good windmill biotope are rarely self-evident or easily recognizable for bystanders. One must have insight into the functioning of a mill. Knowledge of the history of the landscape around the mill is also important. A mill protector can and must therefore never assume that others are automatically aware of the interests at stake. Gaining support is the best way to avoid conflict.

The owner and volunteers of the mill can actively try to increase support by maintaining contact with the environment. It is important to provide information to local residents, the municipality, interest groups, and so on. An active role in local festivities such as a fair also makes the mill visible. Involvement can also be increased by actively involving local residents, small businesses and the local government in activities in and around the mill and by giving them a role in this. Please note: creating support requires more than just opening the windmill one afternoon a month.

   More about creating administrative support

At the De Windotter tower mill from IJsselstein, a successful campaign was conducted against trees that are too high. At De Passiebloem oil mill in Zwolle, support for the mill biotope was increased through intensive communication with local residents and the municipality. Administrative support and administrative influence

Administrative support is gained by adopting a positive and active attitude, by thinking along and making adjustments where possible, and by adopting a reasonable attitude.

A good tool to create administrative support is to draw up a plan for the improvement of the windmill biotope. This provides the opportunity to work on the development of support based on concrete proposals. It is important to realize that other interests are also involved. For example, by elaborating ideas in a plan that is in line with existing government policy but that at the same time contains new elements and responds to current developments, support can be created among policy makers. Such a plan must therefore allow for consultation and negotiation. So don't present the plan as a given! Through consultation and cooperation with local residents, interested parties and stakeholders, the plan must be given further shape and support. Willingness to adjust the plans on certain points ensures that people will continue together more strongly.

Finally, consultation procedures provide many opportunities to object to proposals. However, resistance is the last stage: it is better to prevent it from getting that far. After all, what is included in a plan out of conviction holds up much better than what is enforced through procedures.

Soliciting or unsolicited public authorities for advice is a good way to be involved in plan development at an early stage. See, for example, the Laurentia mill in Milheeze and the Nooit Gedacht mill in Warnsveld. A good example of an integrated approach to create broad support comes from the Molenstichting Drenthe. Their systematic inventory of zoning plans is the Drenthe approach.

   Solicited and unsolicited advice
   Creating support: the Drenthe approach

Solicited and unsolicited advice

A municipality or county may ask a local mill organization or mill expert to advise on a particular problem or policy. The great advantage of such a role is that people are involved in the preparation of plans at an early stage. You can give very specific advice by organizing an excursion for the right people, usually civil servants or an alderman. Another possibility is to participate in round table discussions, work workshops, expert meetings or advisory meetings organized by the civil service. At such meetings, issues are discussed from different angles.

It is of course also possible to give unsolicited advice. This can be done through civil servants, councilors, political parties or administrators. By elaborating ideas in a plan that is in line with existing government policy, but that at the same time contains new elements and responds to current developments, support can be created among policymakers. It is important to consider in advance who can best be approached and where the chance of positive influence is greatest. By using multiple inputs and by approaching the local press, the attention for the advice is increased. A presentation of a report substantiating the advice can provide an extra impulse.


   Participate in government-organized activities, such as round table conferences or expert meetings
   Organizing an excursion to a mill and mill biotope
   Write and present solicited and unsolicited advice

Here is an overview of some of the aspects that can help you to provide efficient and effective advice.

At De Passiebloem oil mill, an intensive PR campaign to preserve the mill has created a favorable climate.

Creating support: the Drenthe approach

In 2003, two board members of the Molenstichting Drenthe successfully attempted to structurally increase the attention for the windmill biotope among administrators in their province. They systematically examined how the 36 windmills in Drenthe were included in zoning plans. They incorporated the results in the report "Inventory of planning schemes for the biotope of the mills in the province of Drenthe. This was presented to the Deputy of Spatial Planning in 2004. The report was also sent to all Drenthe municipalities with the request to take into account the windmill (s) contained therein when revising zoning plans. Millers and biotope guards also received a copy to support their work.

The research has contributed to the inclusion of biotope protection regulations in the zoning plans at several mills. It also ensured that in the Provincial Environmental Plan II (POP) it was included that municipalities are obliged to involve the Molenstichting Drenthe in discussions about preliminary designs for zoning plans.

The research in Drenthe has not only resulted in a good report. The research has also been translated into new policy in favor of the mill. All this was achieved because the initiators based on the following rules:

   Involve the miller and owner in the activities to protect the mill biotope. They should not be surprised by activities around their mill.
   Show what the situation is like at a mill. Make an inventory, indicate the standards, such as the required open space for good windage. This promotes clarity. Moreover, it shows that you are well prepared.
   Address the municipalities about their responsibility to preserve monuments and keep mills running.
   Check whether, and if so how, a windmill is included in the zoning plans. It is possible for everyone to view these plans at municipalities, from 2008 also via the internet.
   Also try to involve the province in solving biotope problems.
   Use meetings of the Guild of Voluntary Millers to provide information on current issues surrounding the mill biotope.
   Appoint a biotope coordinator as the point of contact for millers, mill owners, biotope guards and municipalities.

Responding to spatial developments

As a mill protector one can influence planned developments in various ways. Important ways to defend the mill interest are:

   Participation procedures
   Preparation groups
   Advise as an expert
   For information about zoning plans
   For information about new and old WRO
   For information about Land development plans

Participation in public participation procedures

Participation procedures involve a proposed decision to be taken by the Municipal Executive at the municipality, or by the Provincial Executive at the province. It is mandatory to publish such a resolution. Usually this is done in the regional or local newspaper. A consultation evening can be organized for proposed decisions that affect the interests of citizens, companies or organizations. Those present can express their opinion on such an evening. This can also be done by submitting a written response. The opinions and reactions are compiled and presented to the municipal council or the Provincial Council. In this way, they can include the information in their assessment of the intended decision. All this is discussed in a committee meeting. During such a committee meeting, it is usually possible to comment briefly on the plan or intended decision, provided that you have registered with the registry in advance. The final decision-making takes place in the formal council meeting or Provincial Council meeting. Consultation activities consist of:

   Attending public participation evenings or committee meetings.
   To express your opinion in writing
   Participate in formal objection and appeal procedures.

When you express your opinion through an opinion, pay close attention to the deadline. If the opinion is even one day late, it will formally no longer participate. It is also important to enter the procedure on time. If you have not submitted an opinion before, you cannot object to a decision of the municipality or province later in the procedure.

The example of paltrok mill De Held Jozua in Zaandam tells you about the course of such a procedure.

You can find more about legislation and regulations here.

Participation in preparation groups

When preparing plans (for example for the construction of a new residential area), the municipality often sets up a sounding board or guidance group. Participation in such a group is usually only by invitation. The group is used as a mouthpiece for the stakeholders, but also to make use of specific expertise. By regularly participating in the consultation procedures in an expert manner, or by having broad support within the municipality, there is a greater chance of being asked to participate in a sounding board or guidance group. A personal network can also help with this. The process of planning preparation is long. It is important to take this into account in advance, because participation is most effective when the same person or persons are always participating. Maintain good contact with your own organization throughout the entire process.

Advise as an expert

In order to be able to effectively advise a policymaker, project developer or mill owner about the mill biotope, it is important to list a number of aspects for yourself in advance. Thorough knowledge of the situation will make it appear convincing to you. The following aspects certainly deserve your attention.

Procedural process in planning

Make sure you are aware of the rules of the game that apply in the procedural process surrounding the planning of, for example, a residential area or a park.

The applicable zoning plan

Make sure you are aware of the current (i.e. currently applicable) zoning plan. This tells you where it was built and where it may still be possible to build. The maximum permitted gutter and ridge heights can be read from the plan map.

Inventory of the environment

Make sure that you also have a clear picture of the windmill environment in the field: what is the current height of buildings and plants? Where are the obstacles that already cause wind nuisance? And which growing plants or planned new construction will possibly cause nuisance in the future?

Ask the miller

Always ask the miller for his advice and expertise. He can tell you from practice what the influence of the objects present is on the windage of the windmill. In addition, he often knows a lot about the history of the mill and the area. He will probably also be able to tell you about the relationship with the municipality. Are there any sensitivities or have there been conflicts in the past that may still play a role?

Make the problem transparent

To clarify the problem, you can calculate the maximum permissible obstacle height at different distances from the mill using the biotope formula and with some data from the mill (which can be found in the mill file). Draw circles around the mill on a map as explained in the biotope inventory. A cross-section of the mill and the objects that are too high can also be enlightening. When you indicate in green what does comply with the biotope standard and in red what protrudes above, you get a good impression of the situation at a glance.

Naturally, you should put the importance of good windage first in consultation. You may certainly state the interests in this regard. You provide expert advice. You do not have to weigh up interests: the city council will do that. Oil mill De Passiebloem in Zwolle offers a good example of the results that can be achieved.

Laws and regulations

In the past, the windage of a mill was protected by the so-called wind law, while water mills knew (and know) water law. General legislation that establishes the right to windage from a windmill no longer exists. In general we can say that most mills have no rights with regard to their windage. Threats must therefore be faced on a case-by-case basis. The best option for protecting the windmill biotope is to include a windmill protection zone in the municipal zoning plan.

The zoning plan is part of the Spatial Planning Act. In all likelihood, the new Spatial Planning Act (Wro) will come into effect on 1 July 2008. Procedures initiated before the entry into force of the new law will continue after 1 July 2008 under the effect of the old Spatial Planning Act (WRO). That is why this website contains both general information and details about the operation of the old and the new law.

History: from wind law to mill protection zone

Traditionally, mills were usually built in the open field or on the outskirts of a village or town. There were no wind-obstructing elements. Still, good wind coverage has always been a concern. Encroaching buildings and upright vegetation can be an obstacle. The oldest known regulations that protect the surroundings of windmills from annoying planting date back to around 1600, such as the Patent of the watermills (1598) of the States of Hollandt and Westvrieslandt.

Until the end of the 18th century landlords owned the wind. A permit to run a mill, the so-called wind law, was accompanied by the obligation to pay annual wind rent. The miller was assured of free wind. Good wind entry for polder mills was regulated in so-called polder approvals. In 1798 the "glorious rights" were abolished, and with it the wind rights. As a replacement, ordinances or approvals were issued to guarantee wind entry. Today, however, the zoning plan offers the best options for protecting the mill biotope.

The zoning plan: an important tool

The zoning plan specifies what may be built in an area (height, surface area, location) and what buildings and land may be used for. The latter is important in connection with possible planting. The area surrounding the mill can best be protected if the municipality includes a mill protection zone in its zoning plan. Within this zone, standards apply that are in line with the requirements that the mill sets for its environment. All future plants and buildings in that area must be tested against this.

It is therefore important to ensure that the zoning plan for the area around a mill contains rules that limit the height of buildings and plants as much as necessary and possible. As much as is necessary for the windage and the unobstructed view of the mill. As much as possible taking other interests into account.

A windmill organization does not have to weigh up the interests itself, that is the task of the municipal council. Yet it is not wise to pretend that there are no other interests involved. Existing buildings and plants cannot simply be made unlawful through a new zoning scheme. In the case of items that already exist, rights are obtained. For everything, what can be arranged in consultation is often best preserved. If there is no other option, formal arrangements are necessary to be able to enforce or stop matters. They are also important for recording and making official matters that have been established in good consultation.

Various provinces indicate in their regulations (e.g. Gelderland) or their guidelines for the assessment of zoning plans (e.g. Noord-Holland) that a windmill protection zone must be included in the zoning plan. However, not all municipalities actually include the protection zone in their zoning plans.

The Spatial Planning Act

In all likelihood, the new Spatial Planning Act (Wro) and the Spatial Planning Decree will come into effect on 1 July 2008. This legislation represents a fundamental change in the current spatial planning practice in municipalities. The structural vision and the management regulation are new planning forms. The Article 19 procedure will disappear completely. What remains is the zoning plan.

The role of the province will change. The regional plan is not included in the new Spatial Planning Act. The new Spatial Planning Act obliges provinces to draw up a structural vision for their territory. The role of the province in spatial planning is changing from an assessment to a developing one. The structural vision must give substance to this and establishes the spatial policy of the province for a longer period.

Procedures initiated before the entry into force of the new law will continue after 1 July 2008 under the effect of the old Spatial Planning Act. That is why this website contains both general information and details about the operation of the old law, WRO and the new law, WRO.

   The zoning plan in the new WRO
   The zoning plan in the old WRO
   Article 19 procedure
   Structural vision
   Management regulation
   Views and Appeals
   Plan damage
   Provincial policy

The zoning plan in the new Spatial Planning Act

Every zoning plan must be updated once every ten years. If a municipality is of the opinion that no new developments have occurred in the previous ten years, the zoning plan is still up to date. The plan can then be extended for another ten years. The objection and appeal procedure in accordance with the General Administrative Law Act (Awb) applies. If municipalities fail to update their zoning plans, there will be a sanction. In that case, the municipality may not charge fees for permits issued by the municipality insofar as they relate to the plan concerned. Management regulations should also be revised within ten years of their adoption. Here too, the penalty applies if this period is not observed. After the entry into force of the new Spatial Planning Act, all new spatial plans must also be available in digital form.

The zoning plan procedure will be shortened from just over a year to approximately 26 weeks. The main reason is that zoning plans no longer need to be approved by the province. As far as possible, the province and central government indicate in advance which provincial and national interests should be included in municipal policy. The province and central government can also submit opinions or give directions during the zoning plan procedure.

The new zoning plan procedure is as follows:

   public notice of the design;
   location of the design and accompanying documents available for inspection for 6 weeks and sent to the Provincial Executive and the relevant government services, water boards and municipalities;
   during the period of availability, anyone can submit a written or oral opinion;
   adoption of the zoning plan by the municipal council within 8 weeks after the location for inspection if no views have been submitted, or within 12 weeks if views have been submitted;
   general announcement of (the business content) of the zoning plan by making the plan available for inspection with prior notification and sending it to the Provincial Executive and the relevant government services, water boards and municipalities: within 2 weeks or, if the Provincial Executive or the inspector has submitted views , within 6 weeks after the determination;
   possibility of appeal to the Administrative Jurisdiction Division of the Council of State within 6 weeks after the announcement for interested parties;
   entry into force on the day after the end of the appeal period, being 6 weeks after the announcement.

When someone appeals against the new zoning plan by submitting a notice of appeal, this does not mean that the zoning plan will not come into effect. It can lead to building or planting being started on the basis of the zoning plan. It is therefore important to simultaneously submit a request for interim relief (suspension) to the Administrative Jurisdiction Division.

The mill biotope in the zoning plan

The size of the mill protection zone and the permissible heights for buildings and plants in it must be determined at an early stage in the development process of the zoning plan, so that a solution can be found in time for any conflict situations. It is important not only to weigh up future developments, but also to make an inventory of existing buildings, plants and the like in the mill protection zone.

The zone with height restrictions is indicated on the concept plan map. Particularly when the zoning plan focuses on new developments, an interest must be weighed up between the interest of the mill and other interests in the mill biotope. In this weighing up of interests, the interest of the mill is a general (and therefore important) interest and not just the interest of the miller or the owner.

If the zoning plan leads to damage to the windmill biotope, compensation options should be sought elsewhere in the biotope.

The inclusion of a windmill protection zone means a restriction of the possibilities for other functions in the plan area. As in any plan, the explanatory notes must clarify which considerations are made and how the size of the windmill protection zone and the height permitted in this area was established. You can find a standard version of such an explanation here.

During and after the development process of the zoning plan, the necessary publicity must be given to the consequences that the presence of a windmill entails for the environment. This prevents enforcement problems.

More about planning damage

The full text of the new Spatial Planning Act can be found on the site of the Ministry of Housing, Spatial Planning and the Environment

Here you will find an example of the standard texts for the windmill biotope in the zoning plan with the accompanying explanation.

Tips for writing a notice of objection.

Standard text of zoning regulations

Here you will find a standard text of the destination zone as it can be included in a zoning plan. In order to make the importance of these regulations clear to other parties, it is also important to add an explanation of the zoning regulations. A standard example of such an explanation can be found here.

Zoning regulations

Article 1. Mill protection zone (dual destination) 1.1. Purpose Description

In addition to the other purposes assigned to the land under this zoning plan, the land designated as a 'Mill protection zone' is primarily intended for:

   A protection of the function as a tool of the windmill occurring in this area, in view of, among other things, the windage;
   B protection of the value of this mill as a landscape defining element.

1.2. Building regulations

The following applies to the erection of buildings:

   A. the maximum building height within mill protection zone A (zone A is the first 100 m from the mill) on the plan map is the height indicated within the zone;
   B. within the mill protection zone B indicated on the plan map (zone B starts from 100m from the mill), the maximum height of construction is as high as the size indicated for this zone on the plan map; the maximum building height is the result of the following formula

(distance to the grinder / 140) ¹ + (0.2 * height of the shaft) ² Note 1: For open area this number is 140; for rough and closed areas, the values ​​are 75 and 50 respectively. Note 2: The height of the ash is the height at which the blades are attached, measured from the level from which the height of the structures referred to in the introductory part of Article 1.2 is measured.

   C. Contrary to the provisions under a and b, buildings with a greater height are permitted in the following cases:
       1. it concerns a structure with an existing greater height; or
       2. it concerns a structure, which, seen from the mill, is erected at the rear of existing structures, and where the following conditions are met:
           the height and width remain within the contours (height, width) of the structures behind which it is erected
           b. the structure is built on an existing structure or erected free-standing within a maximum distance of 10 m from existing structures;
           c. the total floor area of ​​structures erected under this provision may not exceed 10% of the structures behind which are being built;
           d. erecting a structure is only permitted insofar as this is possible on the basis of the other purpose applicable to this purpose.

1.3. Determination of use (use other than building)

   It is forbidden to have:
       above-ground structures, installations or equipment;
       planting in the form of trees, shrubs or other upright vegetation;

up to a height that is greater than the height indicated as the maximum in paragraph 1.2 under a and b.

   Contrary to the provisions under a, the use referred to in that paragraph is permitted if it concerns existing use with a greater height.

1.4. Penalty provision

Violation of the provisions of paragraph 1.5 is a criminal offense as referred to in Article 1a under 2 ° Economic Offenses Act³

Note 3: In this (among other things) violation of regulations is punishable by or pursuant to art. 10 WRO (which regulates the adoption of a zoning plan). 1.5. Exemption

1.5.1. The mayor and aldermen can grant an exemption from the provisions of paragraph 1.2 for buildings at a different location, with a greater height or a greater width. The following conditions apply:

   exemption can only be granted if buildings:
       under the conditions as referred to in paragraph 1.2 under c;
       or is not possible by virtue of the provisions elsewhere in these regulations and / or on the plan map at the rear of existing buildings or plants;
       or if the building or other use under the conditions as referred to in paragraph 1.2 under c is not reasonably possible for technical business reasons;
   exemption can only be granted for construction works up to a total floor area of ​​no more than 10% of the buildings under construction;
   granting an exemption is only permitted insofar as the intended construction or use is possible on the basis of the other use (s) applicable to these lands.

1.5.2. The Mayor and Aldermen can grant an exemption from:

   the provisions of paragraph 1.2 under a and under b for the admission of higher buildings;
   the provisions of paragraph 1.3 under a for a use as referred to in that paragraph, insofar as it can be demonstrated through wind tunnel research that the granting of an exemption does not affect the wind catchment. Before the exemption is granted, advice is sought from the De Hollandsche Molen association. The exemption is only included if the wind tunnel method has not already been used in the development of the zoning plan.

1.6. Additional requirements

The Mayor and Aldermen are authorized to impose further requirements on the location and dimensions of buildings or plants in order to protect the interest referred to in paragraph 1.1. Article 2. Mill 2.1. Purpose Description

The grounds indicated on the plan map as 'Mill' are intended for:

   preservation of the historic mill;
   protection of the mill as a municipal or national monument.

2.2. Coordination scheme

The grounds within this zoning are primarily intended as a 'Mill protection zone' as referred to in Article 1. 2.3. Buildings

Only buildings may be erected that serve this purpose. The following rules apply to the erection of buildings:

   buildings may only be erected within the built-up area indicated on the plan map;
   the height of the mill may not exceed the existing height;
   the height of other buildings may not exceed the height of the belt or scaffolding, or the existing height of buildings, whichever is the higher.

You can find an explanation of the standard text for a mill protection zone here.

Explanation of the standard text for a mill protection zone

In the regulation (and on the plan map) a distinction is made between the mill itself and the mill protection zone around it. The destination "Mill protection zone" is a so-called dual destination. This is located as an extra destination on the grounds, next to a main destination such as residential purposes, agricultural purposes, and so on. In doing so, the regulations of the main destination must give way to the regulations of the dual destination 'Mill protection zone'.

The destination "Mill protection zone (dual destination)" (Article 1) This destination rests on the entire zone within which restrictions must be imposed on the height of other functions. The destination also lies on the land designated as a "Mill". Although the protection of the mill within this destination may be obvious, conflict situations can also arise here. After all, the mill has often been given a double function. In addition to its function as a tool, the mill building or mill house sometimes also has a recreational or catering function.

The following subjects are covered in the regulations for this destination.

Purpose Description (1.1 / 2.1) The purpose of this destination is to protect the function of the mill as a tool and to protect the landscape value of the mill. Building regulations (1.2)

   - The most important existing height contours are indicated on the map: this is the height that is permissible in any case. The exact allowable height can be determined using the biotope formula.
   - Two exceptions are mentioned in the regulations. Existing buildings that exceed the maximum height can be maintained. In addition, new buildings can be erected at the "rear" of this building (viewed from the mill). For example, an extension or a detached garage can be built on a house. New buildings in existing buildings may not have a floor area greater than 10% of these existing buildings. The height and width of this new building may not exceed the height and width of the buildings behind which are being built.

Use provision / penalty provision (1.3 / 1.4) This provision has the same effect as the building regulations for plants and the like. A criminalization has been included in the usage provision (an offense as referred to in Article 1a under 2 ° Economic Offenses Act). This means that a sanction is possible for non-compliance with this provision.

Exemption (1.5.1) The above-described possibility for expansion in existing buildings is limited to narrow limits, which cannot be met in all cases. In those cases, an exemption can be provided.

Exemption (1.5.2) The biotope formula will be used in the development of a number of zoning plans. With the aid of the exemption regulation, higher buildings and plants can be allowed if it can be demonstrated using the wind tunnel method that the interests of the windmill are not affected.

Additional requirements (1.6) The mayor and aldermen can impose further requirements on the location and dimensions of buildings.

Article 19 procedure

The Article 19 procedure no longer occurs in the new Spatial Planning Act. Since when the new law comes into force, the building applications already submitted and the ongoing procedures will still be subject to the provisions of the old law, the article 19 procedure will also be involved in 2008.

There are three types of Article 19 procedures:

The first, the so-called project procedure (Article 19, paragraph 1), sets the highest requirements for the substantiation of the (construction) plan. It is no longer a requirement that a new zoning plan will follow in the short term. The council can retain the authority for these projects, but can also delegate them to B&W. The Provincial Executive must grant approval. Anyone who does not agree with the project can object to the exemption within six weeks in accordance with the procedure of the General Administrative Law Act with the body that took the decision (municipal council or B&W) and then proceed to the District Court and the Administrative Jurisdiction Division of the Council of State. One cannot stand up separately against the exemption by G.S. This is linked to the decision of the municipality in the relevant case. Lodging an objection is free of charge, but an appeal must be lodged, both at the Arrondissementsrechtbank and at the Council of State.

In Article 19 procedures, it is often desirable to apply for a provisional relief. This must already be done at the same time as the objection to the municipality, because a building permit that may have been granted can be used immediately. The preliminary injunction must be requested from the President of the District Court, Administrative Law sector. It has to be paid for. The same applies to objections, appeals and preliminary injunctions for the next two categories of Article 19 proceedings.

The second type (Article 19 (2)) are building applications that belong to categories of deviations from zoning plans for which G.S. has determined that no prior approval is required, even when views / reservations have been submitted. The third category (Article 19, paragraph 3) concerns matters for which B&W can always grant an exemption themselves. These are included in Article 20 of the Spatial Planning Decree. Structural vision

In the new law, the structural vision replaces the key planning decisions (at national level), regional plans (at provincial level) and structure plans (at regional and municipal level). The structural vision can be characterized as a strategic policy document. The vision must contain the principles of spatial policy. It must also indicate how one expects to implement that policy. Other authorities cannot derive any rights from the structural vision and are not obliged to implement them immediately. However, it is binding on the determining government body itself.

When the importance of the windmill biotope is properly articulated and endorsed in a municipal structural vision, this offers good opportunities. After all, the structural vision is guiding in the development of a new zoning plan. In that case, the municipality can be expected to translate the statements there into the zoning plan. The realization of a structural vision is often a long process, which mainly depends on making good use of the opportunities for participation, advice and consultation.

Management regulation

Are no spatial developments foreseen in an area? In that case, municipalities can opt in the new Spatial Planning Act to draw up a management bye-law instead of a zoning plan. The management regulation establishes the spatial situation as it is at that time. New developments are not made possible in it. The management regulation is actually a kind of conservative zoning plan.

Views and Appeals

An opinion is a response that an interested party can send to the competent authority in response to a draft decision. For example, it may be a design building permit, a design zoning plan or a design environmental permit. Opinions can be submitted during the period that the draft decision is available for inspection. This term is announced in the local newspaper in which the municipality makes all its announcements.

A view that is submitted too late will be declared inadmissible. The latter means that the writing does not meet the formal conditions and no substantive assessment takes place. The result is that objection and appeal are no longer possible. It is therefore important to submit an opinion in time, otherwise you will be sidelined and you will not be able to influence the further course of the procedure. An exception to this, however, is the situation in which the interested party can demonstrate that he was unable to submit an opinion through no fault of his own. Examples could be a long stay in hospital or abroad. A few main points when writing a viewpoint:

   Address accurately
   Always respond within the official deadline
   Date the piece
   State exactly which procedure is involved
   Clearly indicate the subject
   No clear justification for the "objections"
   Always stay businesslike and keep it as short as possible
   Do not make any claims that you are unsure of yourself

If you are not experienced in writing an opinion, please inquire with larger (mill) organizations in your area. They can often quickly give you tips or send you examples. Incidentally, nobody expects citizens to write letters like a lawyer or civil servant. Arguments are considered, not the style of the letter. As long as the content is clear, that's what matters.

Plan damage

Planning damage occurs if the user or owner of a mill is damaged by the revision of a zoning plan or by following another planning procedure. The right to planning damage is regulated in Article 49 of the Spatial Planning Act. Two things are important to qualify for compensation:

   you could not foresee the damage when you bought the mill or put it into use
   the damage has not already been compensated in any other way

You can submit a claim for damage directly as a result of a procedure under the Spatial Planning Act with the Municipal Executive. The Municipal Executive determines, partly on the basis of the advice of an independent committee, whether there is planning damage. If so, they will also determine whether compensation for the damage should be made and what the amount of the damage (and therefore the compensation to be paid) is.

A planning claim procedure can sometimes take a long time and a lot of discussion can arise about the valuation of the damage. How much was the mill worth and what is the decline in value? It is also not easy to demonstrate the economic damage if the mill can run less. The decrease in the number of milling hours must be demonstrated and also that the lower yields lead to financial damage for the miller or the owner. Only the person who actually causes the damage can submit a request for planning damage. To have a chance, it is a requirement to properly substantiate the request for planning damage. The amount of the requested allowance must also be substantiated. Remember that you have the strongest appeal against planning damage if you yourself have spoken or objected in the preparation of the zoning plan.

In the new Spatial Planning Act, planning damage is regulated in Articles 6.1 to 6.5. New in this is that a loss of income and / or value decrease of two percent is always for the account of the owner and / or the user. The request for damage to the plan must be submitted within five years after the plan has been irrevocably adopted.

Provincial policy

Regional plans are drawn up by the province on the basis of the Spatial Planning Act. A regional plan outlines the desired development of the living environment and indicates how the policy will be implemented. Together with (the spatially relevant parts of) other policy documents, such as the Provincial Environmental Policy Plan and the Provincial Water Management Plan, the regional plans form the provincial policy for the spatial planning of the province.

When drawing up regional plans, the province must take into account government policy, as laid down in the Spatial Planning Memorandum and other government memoranda. The Provincial Executive assess municipal planning decisions, such as zoning plans and Article 19 procedures, against the regional plan applicable to that municipality or against the elaborations that form part of it. For certain policy subjects, it is possible that more rules have been established in addition to the regional plan. You are therefore advised to regularly visit the website of the province in which the mill is located, to see if there are new (policy) intentions.

The province has various options for contributing to the preservation of the mill biotope. The mill and the mill biotope can be mentioned as valuable elements in the text of the regional plan. It can also be mentioned that the details of the protection of the windmill biotope must be regulated in the relevant zoning plan. Mills can also be individually indicated on the cultural-historical value map. With the introduction of the new Spatial Planning Act in mid-2008, the regional plan will lapse. On the basis of this new law, the provincial administration must draw up a structural vision with guiding statements with regard to the spatial development of the province. The restoration of the biotope around polder mill De Dog in Uitgeest is an example of the involvement of the province.

The water board certification

On the basis of the Water Boards Act, water boards can issue regulations containing mandatory and prohibitive provisions. This concerns matters such as the regulation of the maintenance and management of watercourses. The 'mark' is an example of this. The label is a bye-law of the water board, and mainly deals with matters such as:

   design, management and maintenance of flood defenses and watercourses
   dampening or digging ditches

The label states which activities are prohibited in, on or near water management structures (ditches, quays, pumping stations and weirs). Where mills play a role in water management, provisions can be included in the water board approval to prevent wind nuisance. Owners of plants that are too high can then be written to by the water board. Water boards that do not actively do this can be asked by the mill's stakeholders to enforce their own provisions. Below you will find some examples of inspections.

Examples of inspections

Some inspections include provisions to guarantee the proper functioning of mills. These are shown below:

Article 22, paragraph 7, in the approval of the Krimpenerwaard Within a distance of 400 meters from the windmills Beneden Haastrecht and Zuidbroek it is forbidden to make, have, renew, change or clean up works and to apply and have plants.

Article 4.4 of the label of Schieland (1998) With regard to the drainage installations, it is prohibited to move buildings, trees, haystacks or anything else within a distance of 400 meters from the windwater mills De Eendrachtsmolen and the Prinsenmolen as well as from the mills of the molenviergang of the Tweemanspolder. post, have, change or renew.

Article 18 of the approval of the Hollands Noorderkwartier Water Board 2006 It is forbidden to place or have works or plants higher than two meters within a distance of 200 meters from a wind drainage installation. At polder mill De Sluismolen in Koedijk and at polder mill De Dog in Uitgeest, water board approvals are used to protect the mill biotope.

The private law agreement

Private law agreements [definition] can be particularly useful in situations where the municipality (initially) owns land in the mill biotope that will be built on or planted. When selling to a project developer, many municipalities impose conditions on the construction that will take place: the type of housing, the parcelling out, and so on. These agreements can also be used to record the mill interest. It is important that the mill protection with a so-called perpetual clause [definition] is also passed on in later agreements. The private law agreement can also be used when a new development encroaches on the mill biotope. In that case, compensation can be arranged elsewhere in the mill biotope through a private law agreement.

An agreement to protect the mill between private individuals has an additional advantage. In that case, it is possible to exclude the construction of buildings that are 'permit-free' on the basis of the Housing Act. Regardless of what is regulated in the zoning plan, structures that fall into this category may be built under normal conditions. They cannot be excluded via the zoning plan. Land development

land development projects can have consequences for the mill biotope. When, for example, agricultural land is intended for recreational purposes or nature development, there is a chance that upright planting will develop. It is therefore important to monitor the preparation of development plans and, if necessary, to speak up or to object.

Since 2006, the Rural Areas Development Act (WILG) has replaced the Land Development Act of 1985. With regard to rural areas, the WILG is an important starting point for government policy. This act also includes the Investment Budget for Rural Areas (ILG). The provinces and central government have laid down their agreements with regard to the Investment Budget and the associated national budgets for a period of five or seven years in a covenant (agreement).

Each area has its own issues. In one area, the plots of the farmers are too scattered. Lot exchange is a solution for this. Elsewhere, better water management would be of service to both nature and agriculture. The land development then aims to adapt that water management. Elsewhere there are plans for a new road, railway or canal that will cut through rural areas, requiring measures.

A land development committee is set up by the province for each land development project. This committee consists of people from the region: usually someone from the environment or nature conservation corner, one or two farmers (administrators), someone from recreation, and municipal and water board administrators. The tasks of the land development committee are very diverse. In consultation with the region, she draws up the various development plans, advises the province on this, supervises the implementation and takes care of the financial settlement afterwards.

Layout plans are always made available for inspection to provide an opportunity for participation. During information meetings and via websites and newsletters, stakeholders and interested parties are informed about the progress. Development plans are always established by the Provincial Council. It is therefore important to properly inform States members about the interests of the windmill biotope that are at stake.

Around various mills in the Swette-Burd to the east of Grouw, a battle is being fought to have the plans of a land development committee adjusted.

Tree felling and the General Local Regulation

A General Local Regulation (APV) serves to regulate the orderly course of social traffic in the public space. The authority to adopt a General Local Bye-Law rests with the municipal council. The council adopts a bye-law if deemed necessary in the interest of the municipality. In many municipalities, an APV specifies how the tree stock is handled and which rules apply if someone (including the municipality itself) wants to cut a tree. The conditions that must be met can vary greatly from one municipality to another. In some municipalities there is a requirement to replant. For example, a felling permit has been granted at the Nooit Gedacht mill in Warnsveld, but the municipality has committed itself to replanting. When (new) agreements are made about the layout of the windmill biotope, investigate in advance in the General Bye-Laws, the Tree Bye-Laws, or the Felling Bye-Laws, which conditions must be met in order to actually be able to cut down or pollard trees.

Protected town and village view

The protection of town and village views is regulated in the Monuments Act 1988 (Articles 35 to 37). A town or village view is designated to ensure that the cultural-historical value of the area is preserved and enhanced. This must be reflected in the zoning plan.

There is no subsidy scheme for protected city and village views. It is also not the case that buildings that are located in a protected town or village view automatically receive the status of protected monument. The facial protection focuses on the urban design characteristic. The protection of individual objects focuses on the architectural quality and the authenticity of the materials. At the De Windotter tower mill in IJsselstein, the wind catchment and protected cityscape were jointly tackled and improved. The RACM (National Office for Archeology, Cultural History and Monuments) has nominated De Schermer as a protected face.

About the relocation of mills

Before the first Monuments Act came into effect in 1960, mill movements were a common phenomenon. Mills were tools that, when they were no longer needed somewhere, started a second life elsewhere in the country. This was possible because mills could be easily assembled and disassembled as a "kit" and could be transported in parts. For example, during the reclamation of the Schermer, various mills were moved to a more favorable location to help with the emptying of the reclaimed land. Various industrial mills from the Zaan region were also given a new lease of life in the east of the country, because industrialization there only started much later.

Today things are different. The National Office for Archeology, Cultural Landscapes and Monuments (RACM) only grants a permit for relocation if there is a very compelling reason. In principle, the aim is always to maintain a mill in its original location and in its cultural-historical context. Solutions are being sought to ensure acceptable windage.

Nevertheless, government decisions can mean that a mill has to be relocated. This includes, for example, the construction of the HSL and the Betuwelijn. And the development of a business park near Rijnsburg (South Holland) led to the Hoop Doet Leven polder mill being moved 2000 meters. Now it functions again, as part of the Elsgeesterpolder. Urban expansions have also contributed to the relocation of mills. During the construction of a Vinex district near Nieuwegein, the surroundings of the mill were affected to such an extent that relocation was inevitable. The Molens de Leeg Midden Foundation has successfully opposed plans by the land development committee to relocate the Borgmolen near Grouw.

If it is decided to relocate an existing mill (see examples 15, 17 and 18), a number of conditions must always be met:

   The new environment must comply with the cultural-historical context in which the type of mill can function.
   The wind catch must be legally safeguarded, for example by a windmill protection zone.

In the past, also by the RACM, little attention was paid to this second point (see examples 17 and 18). Nowadays, the RACM also imposes this requirement before relocation may take place, such as, for example, the relocation of the Wandenoyen polder mill.